HP Hewlett Packard 16501A LOGIC User Manual

User’s Guide

Publication number 16500-97022

August 1997

For Safety information, Warranties, and Regulatory

information, see the pages behind the Index

HP 16500C /16501A Logic

Analysis System

HP 16500C

HP 16501A

iii

In This Book

Triggering

Intermodule Measurements

File Management

Concepts

This User’s Guide shows you how to use

the HP 16500C Logic Analysis System in

your everyday debugging work.

Chapter 1, “Triggering,” shows you how

to set up the analyzer to trigger on the

various kinds of events present in your

system. Advanced triggering capability

allows you to look at only the program

states of interest when you are solving a

particular problem.

Solving Problems

Application Notes

Glossary

Chapter 2, “Intermodule Measurements,”

shows you how to configure multiple

HP 16500 modules and external

measurement instruments into a single

measurement system in which modules

trigger each other.

Index

Chapter 3, “File Management,” shows you

how to transfer files to and from the

HP 16500C using flexible disks, LAN

interfaces, and other interfaces.

Chapter 4,“Concepts,” gives you a brief

introduction to the ideas underlying the

trigger sequencer and the inverse

assembler, two important components of

sophisticated logic analysis.

Chapter 5, “Solving Problems,” shows you

how to diagnose and correct the more

common types of problems that might

occur while you are making a

measurement.

Chapter 6, “Application Notes,” lists the

various application notes that HP has

published regarding the HP 16500C and

other similar HP logic analyzers. These

notes will give you more information

about specific application problems and how to solve them using an HP logic

analyzer.

See Also

For general information on setup and operation of the HP 16500C, see the

HP 16500C /16501A Logic Analysis System User’s Reference.

For information on programming the HP 16500C using a computer controller

such as a workstation or personal computer, see the HP 16500C/16501A

Logic Analysis System Programmer’s Guide. The Programmer’s Guide is

available from your HP Sales Office.

For information on logic analyzers, oscilloscopes, preprocessors, and other

logic analysis system options, see the User’s Reference manual for those

options.

Contents

1 Triggering

To store and time the execution of a subroutine 1–3

To trigger on the nth iteration of a loop 1–5

To trigger on the nth recursive call of a recursive function 1–6

To trigger on entry to a function 1–8

To capture a write of known bad data to a particular variable 1–10

To trigger on a loop that occasionally runs too long 1–11

To verify that all stacks and registers are restored correctly before

exiting a subroutine 1–12

To trigger after all status bus lines finish transitioning 1–13

To find the nth assertion of a chip select line 1–14

To verify that the chip select line of a memory chip is strobed after

the address is stable 1–15

To trigger when expected data does not appear on the data bus from

a remote device when requested 1–16

To test minimum and maximum pulse limits 1–18

To detect a handshake violation 1–20

To detect bus contention 1–21

Cross-Arming Trigger Examples 1–22

To examine software execution when a timing violation occurs 1–23

To look at control and status signals during execution of a routine 1–24

2 Intermodule Measurements

Intermodule Measurement Examples 2–4

To set up a group run of modules within the HP 16500C 2–4

To start a group run of modules from an external trigger source 2–6

To start an external instrument on command from a module within

the HP 16500 and 16501 mainframe 2–8

To see the status of a module within an intermodule measurement 2–10

To see time correlation of each module within an

intermodule measurement 2–12

To use a timing analyzer to detect a glitch 2–14

To capture the waveform of a glitch 2–15

vii

Contents

To capture state flow showing how your target system processes

an interrupt 2–16

To test a circuit using stimulus-response 2–17

To use a state analyzer to trigger timing analysis of a count-down on

a set of data lines 2–18

To monitor the activity of two coprocessors in a target system 2–19

Special displays 2–21

To interleave trace lists 2–22

To view trace lists and waveforms together on the same display 2–24

Skew Adjustment 2–26

To adjust for minimum skew between two modules involved in

an intermodule measurement 2–27

3 File Management

Transferring Files Using the Flexible Disk Drive 3–3

To save a measurement configuration 3–4

To load a measurement configuration 3–6

To save a trace list in ASCII format 3–8

To save a menu or measurement as a graphic image 3–10

To load system software 3–12

Using the LAN Interface 3–13

To set up the HP 16500C 3–14

To transfer data files from the HP 16500C system to your computer 3–16

To transfer graphics files from the HP 16500C system to your computer 3–18

viii

Contents

4 Concepts

The Trigger Sequencer 4–3

The Inverse Assembler 4–10

Configuration Translation for Analyzer Modules 4–13

5 If You Have a Problem

Analyzer Problems 5–3

Intermittent data errors 5–3

Unwanted triggers 5–3

No Setup/Hold field on format screen 5–4

No activity on activity indicators 5–4

Capacitive loading 5–4

No trace list display 5–5

Preprocessor Problems 5–6

Target system will not boot up 5–6

Slow clock 5–7

Erratic trace measurements 5–7

Inverse Assembler Problems 5–9

No inverse assembly or incorrect inverse assembly 5–9

Inverse assembler will not load or run 5–10

Intermodule Measurement Problems 5–11

An event wasn’t captured by one of the modules 5–11

Contents

Messages 5–12

“Default Calibration Factors Loaded” (HP 16540, 16541, and 16542) 5–12

“. . . Inverse Assembler Not Found” 5–12

“Measurement Initialization Error” 5–13

“No Configuration File Loaded” 5–14

“Selected File is Incompatible” 5–14

“Slow or Missing Clock” 5–14

“State Clock Violates Overdrive Specification” 5–15

“Time from Arm Greater Than 41.93 ms” 5–15

“Waiting for Trigger” 5–16

6 Application Notes

Glossary

Index

Triggering

As you begin to understand a problem in your system, you may realize

that certain conditions must occur before the problem occurs. You

can use sequential triggering to ensure that those conditions have

occurred before the analyzer recognizes its trigger and captures

information.

You set up sequential triggering as follows:

• Select the Trigger menu for the module you are using.

• In the Trigger menu, define terms and associated values to be used

when searching through the sequence.

• In the Trigger menu, select the number of the state sequence level

you want to modify, and enter the appropriate store qualification,

sequence-advance specification, and sequence-Else specification.

If you aren’t familiar with the trigger menus, try working through the

examples in the Logic Analyzer Training Kit manual, or refer to the

User’s Reference for your analyzer.

1–2

Triggering

To store and time the execution of a subroutine

Most systems software of any kind is composed of a hierarchy of functions

and procedures. During integration, testing, and performance evaluation, you

will want to look at specific procedures to verify that they are executing

correctly and that the implementation is efficient. The analyzer allows you to

do this by triggering on entry to the address range of the subroutine and

counting the elapsed time since the trigger state.

1 Select the state analyzer Trigger menu.

2 Set Count to Time.

Setting the Count to Time causes the state analyzer to store a time stamp for

each data point that is stored in trace memory. The trace list will show these

time stamps next to each state.

3 Define a range term, such as Range1, to represent the address range

of the subroutine of interest.

You may need to examine the structure of your code to help determine this.

If your subroutine calls are really procedure calls, then there is likely to be

some code at the beginning of the routine that adjusts the stack for local

variable allocation. This will precede the address of the first statement in the

procedure. If your subroutine has no local storage and is called by a jump or

branch, then the first statement will also be the entry address.

4 Under State Sequence Levels, enter the following sequence

specification:

While storing “no state” Trigger on “In_range1” 1 time

•

While storing “In_range1” Then find “Out_range1” 1 time

•

Store “no state”

•

1–3

Triggering

To store and time the execution of a subroutine

Example

Suppose you want to trigger on entry to a routine called MY_SUB. You can

define the address of MY_SUB in the Format menu, allowing you to reference

the symbol name when setting up the trace specification. Assume that

MY_SUB extends for 0A hex locations. You can set up the trigger sequencer

as shown in the display.

Trigger Setup for Storing Execution of a Subroutine

For processors that do prefetching of instructions or have pipelined

architectures, you may want to add part or all of the depth of the pipeline to the

start address for In_Range1 to ensure that the analyzer does not trigger on a

prefetched but unexecuted state.

1–4

Triggering

To trigger on the nth iteration of a loop

Traditional debugging requires print statements around the area of interest.

This is not possible in most embedded systems designs. But, the analyzer

allows you to view the system’s behavior when a particular event occurs.

Suppose that your system behaves incorrectly on the last iteration of a loop,

which, in this instance, happens to be the 10th iteration. You can use the

analyzer’s triggering capabilities to capture that iteration and subsequent

processor activity.

1 Select the state analyzer Trigger menu.

2 Define the terms LP_START and LP_END to represent the start and

end addresses of statements in the loop, and LP_EXIT to represent

the first statement executed after the loop terminates.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “no state” Find LP_END 1 time

•

While storing “anystate” TRIGGER on LP_START 9 times; Else on

“LP_EXIT” go to level 1

•

Store “anystate”

•

The above sequence specification has some advantages and a potential

problem. The advantages are that a pipelined processor won’t trigger until it

has executed the loop 10 times. Requiring LP_END to be seen at least once

first ensures that the processor actually entered the loop; then, 9 more

iterations of LP_START is really the 10th iteration of the loop. Also, no

trigger occurs if the loop executes less than 10 times: the analyzer sees

LP_EXIT and restarts the trigger sequence. The potential problem is that

LP_EXIT may be too near LP_END and thus appear on the bus during a

prefetch. The analyzer will constantly restart the sequence and will never

trigger. The solution to this problem depends on the structure of your code.

You may need to experiment with different trigger sequences to find one that

captures only the data you wish to view.

1–5

Triggering

To trigger on the nth recursive call of a recursive function

To trigger on the nth recursive call of a recursive

function

1 Select the state analyzer Trigger menu.

2 Define the terms CALL_ADD, F_START, and F_END to represent the

called address of the recursive function, and the start and end

addresses of the function. Define F_EXIT to represent the address of

the first program statement executed after the original recursive call

has terminated.

Typically, CALL_ADD is the address of the code that sets up the activation

record on the stack, F_START is the address of the first statement in the

function, and F_END is the address of the last instruction of the function,

which does not necessarily correspond to the address of the last statement. If

the start of the function and the address called by recursive calls are the

same, or you are not interested in the function initialization code, you can use

F_START for both CALL_ADD and F_START.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “no state” Find “F_END” 1 time

•

While storing “anystate” Then find “F_START” 1 time

•

While storing “anystate” TRIGGER on “CALL_ADD” 20 times Else on

“F_EXIT” go to level 1

•

Store “anystate”

•

As with the trigger specification for “To trigger on the nth iteration of a loop,”

this specification helps avoid potential problems on pipelined processors by

requiring that the processor already be in the first recursive call before

advancing the sequencer. Because it is already in the first recursive call, this

example triggers on the 21st recursive call, which is the 22nd entrance to the

function. Depending on the exact code used for the calls, you may need to

experiment with different trigger sequences to find one that captures only

the data you wish to view.

1–6

Triggering

To trigger on the nth recursive call of a recursive function

Triggering on the 22nd Call of a Recursive Function

1–7

Triggering

To trigger on entry to a function

This sequence triggers on entry to a function only when it is called by one

particular function.

1 Select the state analyzer Trigger menu.

2 Define the terms F1_START and F1_END to represent the start and

end addresses of the calling function. Define F2_START to represent

the start address of the called function.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” Find “F1_START” 1 time

•

While storing “anystate” TRIGGER on “F2_START” 1 time Else on

“F1_END” go to level 1

•

Store “anystate”

•

This sequence specification assumes there is some conditional logic in

function F1 that chooses whether or not to call function F2. Thus, if F1 ends

without the analyzer having seen F2, the sequence restarts.

The specification also stores all execution inside function F1, whether or not

F2 was called. If you are interested only in the execution of F1, without the

code that led to its invocation, you can change the storage specification from

“anystate” to “nostate” for the second sequence term.

1–8

Triggering

To trigger on entry to a function

Triggering on Entry to a Function

1–9

Triggering

To capture a write of known bad data to a particular variable

To capture a write of known bad data to a particular

variable

The trigger specification ANDs the bad data on the data bus, write

transaction on the status bus, and address of the variable on the address bus.

1 Select the state analyzer Trigger menu.

2 Define the terms BAD_DATA, WRITE, and VAR_ADDR to represent

the bad data value, write status, and the address of the variable.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” TRIGGER on “BAD_DATA • WRITE •

VAR_ADDR” one time (you use the Combination trigger term to do this)

•

Store “anystate”

•

Capturing a Bad Write to a Variable

1–10

Triggering

To trigger on a loop that occasionally runs too long

This example assumes the loop normally executes in 14 µs.

1 Select the state analyzer Trigger menu.

2 Define terms LP_START, LP_END, and Timer1 to represent the start

and end addresses of the loop, and the normal duration of the loop.

You can make the sequence specification closer to the problem domain by

renaming Timer1 to LOOP_DUR.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” Find “LP_START” 1 time

•

While storing “anystate” TRIGGER on “LOOP_DUR 14.00 µs” 1 time Else

on “LP_END” go to level 1

•

You will need to start the LOOP_DUR timer (Timer1) upon entering

this state. You do this using the Timer Control field in the menu for

sequence level 2.

Store “anystate”

•

Triggering on a Loop Overrun

1–11

Triggering

To verify that all stacks and registers are restored correctly before exiting a

subroutine

To verify that all stacks and registers are restored

correctly before exiting a subroutine

The exit code for a function will often contain instructions for deallocating

stack storage for local variables and restoring registers that were saved

during the function call. Some language implementations vary on these

points, with the calling function doing some of this work, so you may need to

adapt the procedure to suit your system.

1 Select the state analyzer Trigger menu.

2 Define terms SR_START and SR_END to represent the start and end

addresses of the subroutine.

3 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” Find “SR_START” 1 time

•

While storing “anystate” Then find “SR_END” 1 time

•

While storing “anystate” TRIGGER on “≠ SR_START” 1 time Else on

“SR_START” go to level 2

•

Store “anystate”

•

Verifying Correct Return from a Function Call

1–12

Triggering

To trigger after all status bus lines finish transitioning

In some applications, you will want to trigger a measurement when a

particular pattern has become stable. For example, you might want to trigger

the analyzer when a microprocessor’s status bus has become stable during

the bus cycle.

1 Select the timing analyzer Trigger menu and define a term called

PATTERN to represent the value to be found on the label

representing the status bus lines.

2 Under Timing Sequence Levels, enter the following sequence

specification:

TRIGGER on “PATTERN” > 40 ns

Triggering after lines are done transitioning

1–13

Triggering

To find the nth assertion of a chip select line

1 Select the timing analyzer Trigger menu.

2 Define the glitch/edge1 term to represent the asserting transition on

the chip select line.

You can rename the Edge1 term to make it correspond more closely to the

problem domain, for example, to CHIP_SEL.

3 Under Timing Sequence Levels, enter the following sequence

specification:

TRIGGER on “CHIP_SEL” 10 times

Triggering on the 10th Assertion of a Chip Select Line

1–14

Triggering

To verify that the chip select line of a memory chip is strobed after the address is stable

To verify that the chip select line of a memory chip is

strobed after the address is stable

1 Select the timing analyzer Trigger menu.

2 Define a term called ADDRESS to represent the address in question

and the Edge1 term to represent the asserting transition on the chip

select line.

You can rename the Edge1 term to suit the problem, for example, to

MEM_SEL.

3 Under Timing Sequence Levels, enter the following sequence

specification:

Find “ADDRESS” > 80 ns

•

TRIGGER on “MEM_SEL” 1 time Else on “≠ ADDRESS” go to level 1

•

Verifying Setup Time for Memory Address

1–15

Triggering

To trigger when expected data does not appear on the data bus from a remote

device when requested

To trigger when expected data does not appear on the

data bus from a remote device when requested

1 Select the timing analyzer Trigger menu.

2 Define a term called DATA to represent the expected data, the Edge1

term to represent the chip select line of the remote device, and the

Timer1 term to identify the time limit for receiving expected data.

You can rename the Edge1 and Timer1 terms to match the problem domain,

for example, to REM_SEL and ACK_TIME.

3 Under Timing Sequence Levels, enter the following sequence

specification:

Find “REM_SEL” 1 time

•

TRIGGER on “ACK_TIME > 16.00 µs” 1 time Else on “DATA” go to level 1

•

You will need to use the Timer Control field in the sequence setup for

sequence level 2 to start the ACK_TIME timer upon entering that sequence

level.

This sequence specification causes the analyzer to trigger when the data does

not occur in 16 µs or less. If it does occur within 16 µs, the sequence restarts.

Specifications of this type are useful in finding intermittent problems. You

can set up and run the trace, then cycle the system through temperature and

voltage variations, using automatic equipment if necessary. The failure will be

captured and saved for later review.

1–16

Triggering

To trigger when expected data does not appear on the data bus from a remote device when requested

Triggering When I/O Data Not Returned

1–17

Triggering

To test minimum and maximum pulse limits

1 Select the timing analyzer Trigger menu.

2 Define the Edge1 term to represent the positive-going transition, and

define the Edge2 term to represent the negative-going transition on

the line with the pulse to be tested.

You can rename these terms to POS_EDGE and NEG_EDGE.

3 Define the Timer1 term to represent the minimum pulse width, and

the Timer2 term to represent the maximum pulse width.

You can rename these terms to MIN_WID and MAX_WID. In this example,

Timer1 was set to 496 ns and Timer2 was set to 1 µs. Both timers start when

sequence level 2 is active.

4 Under Timing Sequence Levels, enter the following sequence

specification:

Find “POS_EDGE” 1 time

•

Then find “NEG_EDGE” 1 time

•

TRIGGER on “MIN_WID 496 ns + MAX_WID 1.00 µs” 1 time Else on

“anystate” go to level 1

•

Because both timers start when entering sequence level 2, they start as soon

as the positive edge of the pulse occurs. Once the negative edge occurs, the

sequencer transitions to level 3. If at that point, the MIN_WID timer is less

than 496 ns or the MAX_WID timer is greater than 1 µs, the pulse width has

been violated and the analyzer should trigger. Otherwise, the sequence is

restarted.

Measurement of Minimum and Maximum Pulse Width Limits

1–18

Triggering

To test minimum and maximum pulse limits

Triggering when a Pulse Exceeds Minimum or Maximum Limits

1–19

Triggering

To detect a handshake violation

1 Select the timing analyzer Trigger menu.

2 Define the Edge1 term to represent either transition on the first

handshake line, and the Edge2 term to represent either transition on

the second handshake line.

You can rename these terms to match your problem, for example, to REQ

and ACK.

3 Under Timing Sequence Levels, enter the following sequence

specification:

Find “REQ” 1 time

•

TRIGGER on “REQ” 1 time Else on “ACK” go to level 1

•

Triggering on a Handshake Violation

1–20

Triggering

To detect bus contention

In this sequencer setup, the trigger occurs only if both devices assert their

bus transfer acknowledge lines at the same time.

1 Select the timing analyzer Trigger menu.

2 Define the Edge1 term to represent assertion of the bus transfer

acknowledge line of one device, and Edge2 term to represent

assertion of the bus transfer acknowledge line of the other device.

You can rename these to BTACK1 and BTACK2.

3 Under Timing Sequence Levels, enter the following sequence

specification:

TRIGGER on “BTACK1 • BTACK2” 1 time

Triggering on Bus Contention

1–21

Cross-Arming Trigger Examples

The following examples use cross arming to coordinate measurements

between two instruments. The cross-arming is set up in the Arming

Control menu (obtained by selecting Arming Control in the Trigger

menu). When coordinating measurements between two or more

analyzers, select Count Time so you can correlate the measurements

made by the two analyzers.

See Also

Chapter 2, “Intermodule Measurements.”

1–22

Triggering

To examine software execution when a timing violation occurs

To examine software execution when a timing

violation occurs

The timing analyzer triggers when the timing violation occurs, and when it

triggers, it also sets its “arm” level to true. When the state analyzer receives

the arm signal, it triggers immediately on the present state.

1 Select the timing analyzer Trigger menu.

2 Define the Edge1 term to represent the control line where the timing

violation occurs.

3 Under Timing Sequence Levels, enter the following sequence

specification:

TRIGGER on “glitch/edge1” 1 time

4 Select the state analyzer Trigger menu and accept the default

(anystate) definition for term a.

5 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” TRIGGER on “arm • a” 1 time

•

Store “anystate”

1–23

Triggering

To look at control and status signals during execution of a routine

To look at control and status signals during execution

of a routine

The state analyzer will trigger on the start of the routine whose control and

status signals are to be examined with finer resolution than once per bus

cycle. When it triggers, it will switch its “arm” level true. The timing analyzer

will trigger when it receives the true arm level and detects the transition

represented by glitch/edge1.

1 Select the state analyzer Trigger menu and define term R_START to

represent the starting address of the routine.

2 Under State Sequence Levels, enter the following sequence

specification:

While storing “anystate” TRIGGER on “R_START” 1 time

•

Store “anystate”

•

3 Select the timing analyzer Trigger menu.

4 Define the Edge1 term to represent a transition on one of the control

signals.

5 Under Timing Sequence Levels, enter the following sequence

specification:

TRIGGER on “arm • Edge1” 1 time

1–24

Intermodule Measurements

An intermodule measurement is a measurement that is coordinated

between two or more modules to capture different types of

information related to a problem you are trying to solve. This chapter

shows you how to make several kinds of intermodule measurements.

Intermodule measurements can involve state analyzers, timing

analyzers, oscilloscopes, and pattern generators. The measurement

may be as simple as coordinating the startup of several modules

during a measurement; it may be quite complex and include multiple

arming sequences between modules and external equipment.

For example, you may have a timing analyzer detect the occurrence of

a glitch, and at the same time, have an oscilloscope capture the glitch

waveform and a state analyzer capture the program flow before and

after the occurrence of the glitch. With several types of information

obtained from various analysis modules, you can discover problems

that would otherwise be difficult to identify.

The figure on the opposite page shows how intermodule bus arming

signals are connected between modules inside the HP 16500C and

HP 16501A. Note that any arm input can be driven by any slot, and

that the port input line can drive any slot.

If you are unfamiliar with the basic operation of the Intermodule

Menu, try working the examples in the Logic Analyzer Training Kit.

2–2

Intermodule Measurements

Intermodule Bus Block Functional Diagram

2–3

Intermodule Measurement Examples

To set up an intermodule measurement, you must use the

Intermodule menu. All modules that will participate in the

intermodule measurement must be represented in this menu and their

relationships must be shown under the Group Run field.

To set up a group run of modules within the

HP 16500C

Modules are armed in the configuration tree by either an individual module or

the Group Run field. When armed, a module begins searching for the input

that will satisfy its trigger specification. To obtain a specification that triggers

on the arm signal, specify to trigger on “anystate.”

1 Select the Intermodule menu.

2 Select the second field down from the top on the left, then select

Group Run.

3 Select the name of each module you want to include in the

measurement.

The modules are listed under “Modules” on the right side of the menu.

a Select Group Run if you want to arm this module immediately when

the Group Run begins.

b Select the name of another module if you want the other module to

arm the present one when the other module finds its trigger.

c Select Independent if this module should not be included in the

intermodule measurement.

4 Select the Group Run field in the upper right hand corner.

The group run begins. The modules attached directly to the Group Run field

immediately begin searching for their respective trigger conditions. When a

module finds its trigger, it arms any modules attached to it in the Group Run

tree.

2–4

Intermodule Measurements

To set up a group run of modules within the HP 16500C

The analyzer in slot

B is armed when

the oscilloscope in

slot D finds its

trigger condition.

Oscilloscope Arms State Analyzer in Group Run

2–5

Intermodule Measurements

To start a group run of modules from an external trigger source

To start a group run of modules from an external

trigger source

1 Connect the arm signal from the external instrument or system to the

PORT IN BNC connector on the rear panel of the HP 16500 frame.

2 Select the Intermodule menu.

3 Set up the group run specification.

4 Select the PORT IN/OUT field.

a Select the field under PORT IN Level, then select the level that

matches the external signal that will be applied to the PORT IN BNC

on the HP 16500C rear panel.

The choices are TTL, ECL, and User. The latter allows you to specify a

voltage from −4.00 V to +5.00 V using an onscreen keypad.

b Select the field under PORT IN Edge to change from Rising to Falling

edge and vice-versa for the rear-panel input signal.

c Select Done to leave the PORT IN/OUT Setup menu.

5 Select the Group Run field in the upper right hand corner.

The modules attached directly to the Group Run Armed from PORT IN field

wait for a signal from the PORT IN field.

6 Start the external instrument or system.

When the external instrument sends the proper signal to the PORT IN BNC,

the internal modules attached directly to the Group Run Armed from PORT

IN field are armed and begin searching for their respective trigger conditions.

Modules are armed by modules above them, either an individual module or the

field named Group Run Armed from PORT IN. That is, in the intermodule display,

an arrow pointing to a module to be armed originates in the module providing

the arm signal. See the figure “Oscilloscope Arms State Analyzer in Group Run”

on page 2-5. When armed, a module begins searching for the input that will

satisfy its trigger specification. To obtain a specification of “trigger on the arm

signal,” specify a trigger that equates to “trigger on anything.”

See Also

“To set up a group run of modules within the HP 16500C.”

2–6

Intermodule Measurements

To start a group run of modules from an external trigger source

Both the analyzer in

slot B and the

oscilloscope in slot D

are armed when the

PORT IN signal

arrives.

State Analyzer and Oscilloscope armed from PORT IN

2–7

Intermodule Measurements

To start an external instrument on command from a module within the HP 16500

and 16501 mainframe

To start an external instrument on command from a

module within the HP 16500 and 16501 mainframe

You can set up a module in a group run so that it sends a pulse through the

PORT OUT rear panel BNC. The pulse can be used to start or stop a

measurement in an external instrument or system.

1 Set up the group run specification.

See “To start a group run of modules within the HP 16500C” or “To start a

group run of modules from an external trigger source.”

2 Select PORT IN/OUT.

The PORT IN/OUT Setup menu appears.

3 Select the PORT OUT Source field.

Select Off if no module should drive PORT OUT.

•

Select the name of the module you want to have drive PORT OUT.

•

If you are using Group Run with OR TRIGGER, Port Out is automatically

assigned to the OR TRIGGER group.

4 Set the Type, Polarity, and Output fields to generate the type of signal

the external instrument expects.

To generate the same signal as a 16500B would, set Type to Feedthrough,

Polarity to Active High, and Output to Normal. Normal sends out a standard

TTL signal; Open Collector sinks 128 milliamps in its low state.

5 Select Done in the PORT IN/OUT Setup menu.

See Also

“To set up a group run of modules within the HP 16500C” or “To start a

group run of modules from an external trigger source” in this chapter.

“Configuring Port In/Out” in chapter 2, “Correlating Measurements,” of the

16500C User’s Reference.

2–8

Intermodule Measurements

To start an external instrument on command from a module within the HP 16500 and 16501 mainframe

The analyzer in

slot B drives port

out after finding

its trigger.

Driving the Port Out BNC in an Intermodule Measurement

2–9

Intermodule Measurements

To see the status of a module within an intermodule measurement

To see the status of a module within an intermodule

measurement

1 Select the Intermodule menu.

2 Find the name of the module under the “Modules” list, and read the

status under the module name.

The status can be either Running or Stopped. You can interpret these

indications as follows:

If a module was running and is now stopped, assume it received its arming

signal, triggered, and finished its measurement properly.

•

If a module located below a stopped module on the intermodule

•

configuration tree has received an arming signal and is still running, either

it is still waiting to satisfy its trigger specification or it has not captured

enough information to fill its memory.

If a module below a running module on the intermodule configuration tree

has not received its arming signal, it will not begin running until the upper

module finds its trigger condition.

•

2–10

Intermodule Measurements

To see the status of a module within an intermodule measurement

Both modules are

running because

neither has found

its respective

trigger condition.

Module Status

2–11

Intermodule Measurements

To see time correlation of each module within an intermodule measurement

To see time correlation of each module within an

intermodule measurement

Time correlation in the intermodule menu can help you see when the trigger

occurred for each module and the relative time range of data captured by

that module.

1 Select Time in the Count field of the trigger menu of each logic state

analyzer whose measurement will be time-correlated with the other

modules.

Timing analyzers and digitizing oscilloscopes implicitly count time because

their sampling is driven by an internal clock, rather than an external state

clock. See the User’s Reference for your logic state analyzer for details on

how to count time with the analyzer.

2 Select the Intermodule menu.

3 Select the Group Run field in the upper right hand corner.

Once the measurement has started, view the time correlation bars at the

bottom of the Intermodule Menu. The “T” in each bar indicates the relative

time at which that module found its trigger condition. The yellow portion of

each bar indicates the start and stop points of the acquisition window of the

associated module relative to the other modules in the measurement.

2–12

Intermodule Measurements

To see time correlation of each module within an intermodule measurement

This portion of the bar

indicates the relative

time range of data

acquired by this

module.

T indicates the time

at which the trigger

was found.

Module Time Correlation

2–13

Intermodule Measurements

To use a timing analyzer to detect a glitch

The following setup uses a state analyzer to capture state flow occurring at

the time of the glitch. This can be useful in troubleshooting. For example, you

might find that the glitch is ground bounce caused by a number of

simultaneous signal transitions.

1 Select the Intermodule menu.

2 Select the timing analyzer from the Modules list and set it to Group

Run. Select the state analyzer and set it to respond to the arm signal

from the timing analyzer.

You must have fully independent state and timing analyzers to make this type

of measurement. For example, though the HP 16550A can be configured to

use some of its channels for a state analyzer and some for a timing analyzer, it

cannot present those analyzers independently for intermodule measurements.

3 Select the timing analyzer Trigger menu.

4 Select an Edge term. Then assign glitch detection “*” to the channels

of interest represented by the Edge term.

5 Select the state analyzer Trigger menu.

6 Set the analyzer to trigger on any state and store any state.

7 Select Group Run in the upper right corner of the display.

If you don’t see the activity of interest in the state trace, try changing the

trigger position using the Acquisition Control field in the Trigger menu of the

state analyzer. By changing the Acquisition mode to manual, you can position

the trigger at any state relative to analyzer memory.

The timing analyzer can detect glitch activity on a waveform. A glitch is defined

as two or more transitions across the logic threshold between adjacent timing

analyzer samples.

2–14

Intermodule Measurements

To capture the waveform of a glitch

The following setup uses the triggering capability of the timing analyzer and

the acquisition capability of the oscilloscope.

1 Select the Intermodule Menu.

2 Select the timing analyzer from the Modules list and set it to Group

Run. Select the oscilloscope module and set it to respond to the arm

signal from the timing analyzer.

3 Select the timing analyzer module.

4 Select the Trigger menu, and within the menu, select an Edge term.

5 Assign glitch detection "*" to the channel of interest represented by

the Edge term.

This will usually be the same channel monitored by the oscilloscope.

6 Select the oscilloscope Trigger menu, and set Mode to Immediate.

7 Select the Group Run field in the upper right corner.

If you have trouble capturing the glitch waveform on the oscilloscope, try

adjusting the skew in the Intermodule menu, so the oscilloscope triggers

earlier.

A timing analyzer can trigger on a glitch and capture it, but a timing analyzer

doesn’t have the voltage or timing resolution to display the glitch in detail. An

oscilloscope can display a glitch waveform with fine resolution, but cannot

trigger on glitches, combinations of glitches, or sophisticated patterns involving

many channels.

2–15

Intermodule Measurements

To capture state flow showing how your target system processes an interrupt

To capture state flow showing how your target system

processes an interrupt

Use an oscilloscope with a sample rate faster than the microprocessor clock

rate to trigger on the asynchronous interrupt request.

1 Select the Intermodule menu.

2 Select the oscilloscope from the Modules list and set it to Group Run.

Select the state analyzer module and set it to respond to the arm

signal from the oscilloscope module.

3 Select the oscilloscope module.

4 Select the Trigger menu, and set the mode to Edge trigger.

5 Select the state analyzer module.

6 Select the Trigger menu of the state analyzer, and set the analyzer to

trigger on any state and store any state.

7 Select Group Run from the upper right corner of the display.

When the interrupt occurs, the oscilloscope will trigger, subsequently

triggering the state analyzer.

If the analyzer doesn’t capture the expected interrupt activity, ensure that

the interrupt isn’t masked due to the actions of other program code.

This setup can help you answer questions like the following:

• Does the processor branch to the proper interrupt handling routine?

• Are registers and status information saved properly?

• How long does it take to service the interrupt?

• Is the interrupt acknowledged properly?

• After the interrupt is serviced, does the processor restore registers and

status information and continue with the interrupted routine as expected?

You can use the state analyzer to check the address of the interrupt routine as

well as to see if interrupt processing is done as expected. Using a preprocessor

and inverse assembler with the state analyzer will make it easier to read the

program flow.

2–16

Intermodule Measurements

To test a circuit using stimulus-response

1 Select the Intermodule menu.

2 Select the pattern generator from the Modules list and set it to Group

Run. Select the oscilloscope module and set it to respond to the arm

signal from the pattern generator. Select the state analyzer and set it

to respond to the arm signal from the pattern generator.

3 Load the pattern generator with the proper patterns to simulate the

signals from the driving hardware.

4 Insert the “Signal IMB” instruction at the desired point in the pattern

generator program.

The arm signal is programmable. It can occur anywhere in the pattern

generator cycle.

5 Select the oscilloscope Trigger Menu. Set the oscilloscope to trigger

on signals of interest in the circuit under test.

6 Select the state analyzer Trigger Menu. Set the analyzer to trigger on

addresses, data, or status conditions of interest, and to store any

state or states of interest.

7 Select Group Run from the upper right corner of the display.

The pattern generator will begin its cycle, and will arm the oscilloscope and

state analyzer.

In the early stages of system design and integration, you may want to test a

circuit when the driving hardware that will stimulate it has not yet been

designed or fabricated. You can also use the pattern generators with the logic

analyzer to test PC boards when no board-test system is available.

The HP 16522A pattern generator for the HP 16500C avoids the inconvenience of

having to stack several signal generators on top of each other, with all of the

cable connections required for those signal generators. Additionally, you have a

single interface to access all the test modules in your measurement.

See Also

The HP 16522A User’s Reference for the procedures for operating the

pattern generator.

2–17

Intermodule Measurements

To use a state analyzer to trigger timing analysis of a count-down on a set of data

lines

To use a state analyzer to trigger timing analysis of a

count-down on a set of data lines

1 Select the Intermodule menu.

2 Select the state analyzer from the Modules list and set it to Group

Run. Select the timing analyzer and set it to respond to the arm signal

from the state analyzer.

3 Select the state analyzer Trigger menu.

4 Set the state analyzer to trigger on the label and term that identify the

start of the count-down routine.

If you are not familiar with the procedures for setting up a trigger condition,

see chapter 1.

5 In the timing analyzer Trigger Menu, set the timing analyzer to trigger

on any state and store any state.

6 Select Group Run from the upper right corner of the display.

Your target system may include various state machines that are started by

system events: interrupt processing, I/O activity, and the like. The state analyzer

is ideal for recognizing the system events; the timing analyzer is ideal for

examining the step-by-step operation of the state machines.

2–18

Intermodule Measurements

To monitor the activity of two coprocessors in a target system

To monitor the activity of two coprocessors in a target

system

Debugging coprocessor systems can be a complex task. Replicated systems

and contention for shared resources increase the potential problems. Using

two state analyzers with preprocessors can make it much easier to discover

the source of such problems. For example, you may wish to set up one

analyzer to trigger only when a certain problem occurs, and set up the other

analyzer to be armed by the first analyzer so that it takes its trace only when

the first analyzer recognizes its trigger. This will let you observe the behavior

of both coprocessors during the occurrence of a problem.

1 Select the Intermodule menu.

2 Select the first state analyzer from the Modules list and set it to

Group Run. Select the second state analyzer and set it to respond to

the arm signal from the first analyzer.

3 Select the Trigger menu of the first analyzer.

4 Set the first analyzer to trigger on the problem condition.

Some problems may involve complex sequences of conditions. See chapter 1,

“Triggering,” for more information on defining a trigger sequence.

5 Select the Trigger menu of the second analyzer.

6 Set the second analyzer to trigger on any state and store any state.

2–19

Intermodule Measurements

To monitor the activity of two coprocessors in a target system

7 Select Group Run from the upper right corner of the display.

After the measurement is complete, you can interleave the trace lists of both

state analyzers to see the activity executed by both coprocessors during

related clock cycles.

You can use a similar procedure if you have only one processor, but wish to

monitor its activity with that of other system nodes, such as chip-select lines,

I/O activity, or behavior of a watchdog timer. In some instances it may be

easier to look at related activity with a timing analyzer.

See Also

“Special Displays” in this chapter.

“To use a state analyzer to trigger timing analysis of a count-down on a set of

data lines” in this chapter.

2–20

Special displays

Interleaved Trace Lists

Interleaved trace lists allow you to view data captured by two or more

analyzers in a single trace list. When you interleave the traces, you see

each state that was captured by each analyzer. These states are

shown on consecutive lines.

You can interleave state listings from HP 16510B, 16540A, 16540D,

and 16550A state analyzers, when two or more are used together in a

group run. Interleaved state listings are useful when you are using

multiple analyzers to look at interaction between two or more

processors. They are also useful when you need more analysis width

than is available in one analyzer.

Mixed Display Mode

The Mixed Display mode allows you to show state listings and

waveforms together on screen, if all were obtained by modules within

the HP 16500C and 16501A frame. State listings are shown at the top

of the screen and waveform displays are shown at the bottom. You can

interleave state listings from two analyzers at the top of the screen, if

desired. You can display waveforms from two oscilloscopes or timing

analyzers at the bottom of the screen.

2–21

Intermodule Measurements

To interleave trace lists

1 Set up the analyzers whose data you wish to interleave as part of a

group run.

You won’t need to do this if the two measurement modules for which you

want mixed display are really part of the same module. For example, you

might have an HP 16550A state/timing analyzer configured as two separate

analyzers, one a state analyzer, the other a timing analyzer. You can use

mixed display to view the timing analyzer waveform with the trace lists from

the state analyzer.

2 Select the first state analyzer whose trace list will be shown in the

interleaved display.

3 Select Trigger from the menu field and set Count to Time.

The system uses the time stamps stored with each state to determine the

ordering of states shown in an interleaved trace list.

4 Repeat steps 2 and 3 for the second state analyzer.

5 Select Listing Display from the Menu field.

6 Select one of the label fields in the trace list display, then select

Interleave.

7 Select the name of the analyzer whose trace list will be interleaved

with the first analyzer. Then choose the label that you want to

interleave from the selected analyzer.

Interleaved data is displayed in yellow. Trace list line numbers of interleaved

data are indented. The labels identifying the interleaved data are shown

above the labels for the current analyzer, and are displayed in yellow.

If you have problems with the procedure, and you are using two independent

analyzers, first ensure that the analyzers are set up as part of a group run.

Ensure that each analyzer is set to Count Time and that each analyzer has an

independent clock from the target system.

You can interleave trace lists from state analyzers that were configured as part

of a group run or from state analyzers that are configured as separate analyzers

within the same measurement module. In the first case, you might have two

HP 16550A analyzers configured in a group run; in the second, you might have a

single HP 16550A configured as two state analyzers. The interleaved trace lists

are shown as a time-correlated, state-to-state display.

2–22

Intermodule Measurements

To interleave trace lists

Labels for the

interleaved states are

shown above those for

the primary analyzer.

Interleaved states

are shown in yellow

with line numbers

indented from those

of the primary

analyzer.

Interleaved Trace Lists on the HP 16550A

“To set up a group run of modules within the HP 16500C” in this chapter.

See Also

2–23

Intermodule Measurements

To view trace lists and waveforms together on the same display

To view trace lists and waveforms together on the

same display

1 Set up the modules whose data you wish to view as part of a group

run.

You won’t need to do this if the two measurement modules for which you

want mixed display are really part of the same module. For example, you

might have an HP 16550A state/timing analyzer configured as two separate

analyzers, one a state analyzer, the other a timing analyzer. You can use

mixed display to view the timing analyzer waveform with the trace lists from

the state analyzer.

2 Select the module for which you wish to show waveforms.

This might be an oscilloscope module or a timing analyzer.

3 Select the label field to the left of the waveform display area twice,

then choose the waveforms to be shown.

When you double-select the label field to the left of the waveform display

area, a new menu appears that allows you to insert and delete signals and

choose the relative display size and position for the signals.

4 Select the state analyzer.

5 Set the Trigger menu of the state analyzer and set the Count field to

Time.

Timing analyzers and digitizing oscilloscopes implicitly count time because

their sampling is driven by an internal clock, rather than an external state

clock. See the manual for your logic state analyzer for details on how to count

time with the analyzer.

6 To insert state listings, select any label field from the state listing.

From the popup that appears, select the desired label to insert.

7 Select Mixed Display from the menu field.

8 Select Group Run from the upper right corner of the display.

You can position X and O Time markers on the waveform display, if desired.

Once set, the time markers will be displayed in both the listing and the

waveform display areas. Note that even if you set X and O Time markers in

another display, you must also set the Time markers in the Mixed Display if

Time markers are desired.

2–24

Intermodule Measurements

To view trace lists and waveforms together on the same display

You can use the Mixed Display feature in the state analyzer menus to show both

waveforms and trace lists in the same display, making it easier to correlate the

events of interest.

If you are using mixed display as part of a group run, you may need to adjust

intermodule skew to ensure proper time correlation and display results.

X and O markers from

the waveform display

are shown in their

relative position on the

state display.

Mixed Display using the HP 16550A and HP 16532A

See Also

“To set up a group run of modules within the HP 16500C” in this chapter.

“Skew Adjustment” in this chapter.

2–25

Skew Adjustment

You can modify the skew or timing deviation between modules within

the intermodule measurement. This allows you to compensate for any

known delay of the system under test, or to compare two signals by

first removing any displayed skew between the signal channels.

Skew adjustments can correct module delays to within 2 ns of other

modules. Note that the module or channel that is used as the trigger is

normally the reference channel, and adjustments are normally made

to deskew the nonreference channels.

2–26

Intermodule Measurements

To adjust for minimum skew between two modules involved in an intermodule measurement

To adjust for minimum skew between two modules

involved in an intermodule measurement

1 Connect an input signal from each module to the same signal.

An ideal signal for testing skew is a single-shot signal with fast risetime. Such

a signal simplifies triggering and makes it easier to correlate the input event

between the modules. Ensure that you use proper probe grounding for

maximum signal fidelity.

2 Select the Intermodule menu.

3 Set up both modules so they will begin searching for the trigger

immediately when a group run begins.

This setup focuses mostly on trying to eliminate probe skew and internal

triggering delays. You can use other intermodule setups as well. For example,

you may be interested in nullifying the effects of the internal arming delay in

a setup where one module arms another.

4 Set up the trigger conditions for each module.

This will depend upon your input signal. For example, if you are adjusting

intermodule skew using a single-shot pulse with a rising edge, set a timing

analyzer to trigger on a rising edge using the Edge1 term, and the

oscilloscope to trigger on a positive slope.

5 Select the Display or Waveform menu in one of the modules.

6 Set up the display so that both input waveforms are displayed

simultaneously.

You do this by selecting the label field to the left of the display twice. The

second selection brings up a new menu that allows you to insert or delete

waveforms. You can delete all but the waveform of interest from the first

module, then add the waveform of interest from the second module. Select

Done when finished.

7 Select Group Run.

You may now need to trigger the signal of interest, if, for example, it is

activated by a push button. You may need multiple events to capture good

waveforms for both measurement modules. Remember that the oscilloscope

captures far more accurate waveform data than the timing analyzer. Thus, if

the waveforms do not match exactly, it may only be because the waveform

edge did not meet the timing analyzer’s setup and hold time specifications for

a particular sampling period.

2–27

Intermodule Measurements

To adjust for minimum skew between two modules involved in an intermodule

measurement

8 Record the differences shown by the two modules.

You can use the X and O markers to measure the differences in delays.

9 Select the Intermodule Menu.

10 Select Skew, then enter a skew correction value for one of the

modules using the knob or the keyboard.

11 Return to the module waveform display and recheck the skew

adjustment.

You will need to repeat steps 7 through 11 as needed until the trigger events

on the two waveforms match as closely as possible.

Before making an intermodule measurement, you should remove skew between

the modules to ensure that a simultaneous arm signal to both modules results in

captures of the same events around the trigger.

Skew Removal Between Timing Analyzer and Oscilloscope

2–28

File Management

A host computer such as a PC or UNIX workstation can enhance the

HP 16500C in many ways. You can use the host to store configuration

files or measurement results for later review. Screen images from the

HP 16500C can be saved in bitmap files for inclusion in reports

developed using word processors or desktop publishing tools. Or, you

can develop programs on the PC that manipulate measurement results

to satisfy your problem-solving needs.

This chapter shows you some examples of how to transfer files

between a host computer and the HP 16500C, using the flexible disk

drive and the LAN Interface. If you aren’t familiar with basic flexible

disk drive operations or if you need help setting up or understanding

the use of the LAN Interface, see the HP 16500C/16501A User’s

Reference.

You can also use a host computer to send the HP 16500C complex

command sequences—allowing you to automate your measurement

tasks. If you want to program the HP 16500C using a host computer,

see the HP 16500C/16501A Logic Analysis System Programmer’s

Guide, available from your HP Sales Office.

3–2

Transferring Files Using the Flexible Disk Drive

Because the flexible disk drive on the HP 16500C will read and write

double-sided, double density or high-density disks in MS-DOS format,

it is a useful tool for transferring images to and from IBM

PC-compatible computers as well as other systems that can read and

write MS-DOS format. You can save measurement configuration files,

measurement results, and even menu and measurement images from

the screen.

This section shows you how to use the flexible disk drive to:

• save a measurement configuration

• load a measurement configuration

• save a trace list in ASCII format

• save a screen image (such as an oscilloscope display or menu)

• load system software

If you need more information on the basic flexible disk drive

operations, see the HP 16500C/16501A Logic Analysis System

User’s Reference.

3–3

File Management

To save a measurement configuration

You can save measurement configurations on a 3.5-inch disk or on the

internal hard disk for later use. This is especially useful for automating

repetitive measurements for production testing.

1 Select System from the module field.

2 Select Hard Disk or Flexible Disk from the menu field.

3 Select Store from the disk operations field.

4 Select the module for which you want to save the configuration from

the module list.

You can save the configuration for individual modules. The choice “System”

saves only the mainframe configuration. The choice “All” saves the

mainframe configuration and that of all measurement modules.

5 Specify a file name into which to save the configuration using the “to

file” field.

6 Specify a descriptive comment for the file using the “file description”

field.

7 Select Execute.

3–4

File Management

To save a measurement configuration

Saving the Oscilloscope Configuration for Skew Testing

If you want to save your file in a directory other than the root, you can select

Change Directory from the disk operations field. Then type the name of the

desired directory in the directory name field, or select it from the list of visible

directories using the knob.

3–5

File Management

To load a measurement configuration

You can quickly load a previously saved measurement configuration, saving

the trouble of manually setting up the measurement parameters for each

module.

1 Select System from the module field.

2 Select Hard Disk or Flexible Disk from the Menu field.

Your choice here depends on where you saved the configuration.

3 Select Load from the disk operations field.

4 Select the module for which you want to load a configuration from

the module list.

You can load configurations for individual modules. The choice “System”

loads only the mainframe configuration. The choice “All” loads the mainframe

configuration and that of all measurement modules.

However, you can only load configurations that are defined in the

configuration file itself. Thus, if you select System, then select a file that

contains only an analyzer configuration, the configuration will fail.

If you save an analyzer configuration as “All,” then attempt to reload that

configuration into a particular measurement module, configuration will fail.

Also, configurations are slot dependent. If you save a configuration for a

particular module, rearrange the modules within the HP 16500C, then try to

reload the configuration, the configuration will not load.

5 Specify a file name from which to load the configuration using the

“from file” field.

6 Select Execute.

3–6

File Management

To load a measurement configuration

Loading Configuration for all HP 16500C Modules and the System

3–7

File Management

To save a trace list in ASCII format

Some HP 16500C displays, such as file lists and trace lists, contain columns of

ASCII data that you may want to move to a PC for further manipulation or

analysis. You can save these displays as ASCII files, using a procedure similar

to that for creating graphics images. While a graphics capture saves only the

data shown onscreen, saving the display as an ASCII file captures all data in

the list, even if it is offscreen.

1 Insert a DOS-formatted 3.5-inch disk in the flexible disk drive.

2 Set up the menu you want to capture, or run a measurement from

which you want to save data.

Remember that only displays that present lists of textual data can be

captured as ASCII files.

3 Select Print Disk from the Print menu.

4 Select the Filename field and specify a file name to which the screen

will be printed.

5 Select ASCII (ALL) from the Output Format field.

If the current display contents can’t be saved as an ASCII file, this option will

not be present in the Output Format field.

6 Select Flexible Disk from the Output Disk menu.

7 Select Execute.

3–8

File Management

To save a trace list in ASCII format

68332EVS - State Listing

Label

ADDR

CPU32 Mnemonic

STAT

__________ _____ ______________________________________ _________________

406F4

0FF7A

0FF7C

40992

ANDI.L #********,(A6)+

0004 data write

Opcode Fetch

Data Write

Opcode Fetch

Data Write

06F6 data write

BSR.B

0004093E

40994 nu MOVE.B ********,(****,A7)

0FF76

0FF78

4093E

40940

40942

40944

40946

40948

4094A

4094C

4094E

0004 data write

0994 data write

MOVE.W #03FF,00FFFA46

03FF pgm read

00FF pgm read

FA46 pgm read

MOVE.W #6B70,00FFFA72

6B70 pgm read

00FF pgm read

FA72 pgm read

RTS

Data Write

Opcode Fetch

Data Read

40950 nu MOVE.L D1,-(A7)

0FF76

0FF78

40994

40996

40998

4099A

0004 data read

0994 data read

MOVE.B 00020001,(0004,A7)

0002 pgm read

Data Read

Opcode Fetch

0001 pgm read

0004 pgm read

Part of a Trace Listing Saved as an ASCII File

3–9

File Management

To save a menu or measurement as a graphic image

You can save menus and measurements to disk in one of four different

graphics formats.

1 Insert a DOS-formatted flexible disk in the flexible disk drive.

2 Set up the menu whose image you want to capture, or run a

measurement from which you want to save data.

3 Select Print Disk from the Print menu.

4 Select the Filename field and specify a file name to which the screen

will be printed.

5 Select the Output Format field and specify the output format for the

graphics file.

Choose one of the following formats:

B/W TIF (SCREEN) is a black and white Tagged Image File Format file in

TIFF version 5.0 format

•

Color TIF (SCREEN) is a color TIFF file in TIFF version 5.0 format

•

PCX (SCREEN) is a color PCX file (PCX is the PC Paintbrush and

Publisher’s Paintbrush format from ZSoft)

•

EPS (SCREEN) is a black and white Encapsulated PostScript file

•

6 Select Flexible Disk from the Output Disk menu.

7 Select Execute.

3–10

File Management

To save a menu or measurement as a graphic image

An Oscilloscope Display Saved as a TIF Image

3–11

File Management

To load system software

1 Insert the first disk containing the system software.

2 Select System from the module field.

3 Select Hard Disk from the menu field.

4 Select Change Directory from the disk operation field.

5 Select the directory SYSTEM using the knob, and select Execute.

6 Select Flexible Disk from the menu field.

7 Select Copy from the disk operation field.

8 Select the file you want to update using the knob, then select Execute.

The selected file is copied to the \SYSTEM directory on the hard disk.

Repeat steps 7 and 8 for all files you need to update. If you have more than

one disk from which you want to copy files, turn the knob after changing

disks. This ensures that the HP 16500C will read the directory on the new

disk.

3–12

Using the LAN Interface

The LAN Interface of the HP 16500C extends the Logic Analysis

System by making it look like a NFS (Network File System) node.

Using NFS utilities for the PC or NFS on a UNIX workstation, you can

transfer files to and from the HP 16500C as if it were a disk drive

attached to your machine. The LAN Interface also creates virtual

directories and files for measurement configurations and results, so

you can store and retrieve these as though they were ordinary files.

This section shows you how to use the LAN interface do the following:

• set up the HP 16500C configuration

• retrieve measurement data from a module in the HP 16500C

• transfer images of HP 16500C menu and result screens to your host

computer

If you have not connected your HP 16500C to the network, installed

network software, or learned basic network commands, see the

chapter on connecting to your LAN in the HP 16500C/16501A User’s

Reference before performing the tasks in this chapter.

3–13

File Management

To set up the HP 16500C

You can set up the HP 16500C from the front panel, or via the LAN. To set up

the system via the LAN, you can use one of three methods:

Copy a configuration file from your PC or workstation to one of the files

called setup.raw in the HP 16500C directory tree.

•

Remotely load a configuration file into the system from one of the local

disk drives of the HP 16500C.

•

Program the system directly, using the programming commands described

in the optional HP 16500C System Programmer’s Guide.

•

Example

You want to load a configuration file called “486_bus” from your local

computer into an HP 16550A state/timing module. The HP 16550A is installed

in slot B of the HP 16500C mainframe. The mainframe is mounted on your

network as disk drive L: (assuming you are using a PC as the host).

To load the configuration file, enter the following at the DOS prompt:

C:\> copy 486_bus L:\slot_b\setup.raw

If you are using a UNIX system, you might use the cp command. In the

Microsoft Windows environment, you can use the File Manager.

3–14

File Management

To set up the HP 16500C

Example

You want to load a configuration file called “486_bus” from the hard disk of

the HP 16500C into an HP 16550A state/timing module. The HP 16550A is

installed in slot B of the HP 16500C mainframe. To load the configuration file

from the HP 16500C hard disk, you need to send the programming command

to the analyzer. The syntax of the command is:

:MMEMory:LOAD:CONFig <filename>[,<disk drive>][,<slot number>]

In this case, the disk drive parameter, will be “INT0,” which indicates the

hard disk. The slot number will be 2, because the HP 16550A is installed in

slot B. To load the configuration file, enter the following command at the

DOS prompt:

C:\> echo :MEM:LOAD:CON ’486_BUS’,INT0,2 L:\system\program

If you are using a UNIX system, you can use the UNIX echo command.

See Also

The HP 16500C System Programmer’s Guide for more information on

programming command syntax.

To copy files to the setup.raw file locations, or to send commands to the system

at the \system\program file location, you must be connected to the HP 16500C

system as the control user.

3–15

File Management

To transfer data files from the HP 16500C system to your computer

To transfer data files from the HP 16500C system to

your computer

You can transfer data from the HP 16500C system to your PC or workstation

by copying files. Data files in binary format are available in file locations

\slot_x\data.raw. These binary files can be transferred to your computer and

then reloaded into the HP 16500C system later.

For some types of measurement modules, data files in ASCII format are also

available. The ASCII data files are in file locations

\slot_x\data.asc\{analyzer name}\{label name}.txt

Depending on which measurement module you are using, there might not be

a subdirectory corresponding to an analyzer name. There is an ASCII data file

corresponding to each label name you have created in the measurement

module.

1 Set up the system for the measurement you want to make.

You can do this from the front panel or remotely.

2 Run the analyzer to acquire data.

You can do this from the front panel or remotely.

3 If you would like the data in binary format, copy the file data.raw to

your computer from the file location \slot_{x}\data.raw

The x represents the slot in which the measurement module is installed.

4 If you would like the data in ASCII format, copy the files

corresponding to the labels you want to view from the file location

\slot_{x}\data.asc\{analyzer name}\{label name}.txt

Depending on which measurement module you are using, there might not be

a subdirectory corresponding to an analyzer name.

3–16

File Management

To transfer data files from the HP 16500C system to your computer

Example

You have an HP 16550A state/timing analyzer installed in slot C of your

HP 16500C mainframe. The name of analyzer 1 of the HP 16550A is

68000_BUS. You have created some labels under analyzer 1 of the

HP 16550A, including one called “addr_lo.” The directory structure of the

HP 16500C system looks like this:

After setting up a measurement and acquiring data, you want to analyze the

data for label addr_lo on your PC. To copy the ASCII data to your local

computer, enter the following command at the DOS prompt:

C:\ copy L:\slot_c\data.asc\68000_bus\addr_lo {local path

name}

If you are using a UNIX system, you might use the cp command. In the

Microsoft Windows environment, you can use the File Manager.

3–17

File Management

To transfer graphics files from the HP 16500C system to your computer

To transfer graphics files from the HP 16500C system

to your computer

The current display of the HP 16500C is available in four different formats.

1 Set up the display you want to transfer.

2 Copy the file in the format of your choice from the directory

\system\graphics.

The file screen.tif is a color Tagged Image File Format file, in TIFF version

5.0 format.

•

The file screenbw.tif is a black and white TIFF file in TIFF version 5.0

format.

•

The file screen.pcx is a color PCX file. (PCX is the standard format of PC

Paintbrush and Publisher’s Paintbrush.)

•

The file screenbw.epi is a black and white Encapsulated PostScript file in

EPS version 3.0 format.

•

You can also save the current display to a file on one of the local HP 16500C

disk drives, using the Print to Disk function. You can then transfer the file

from the HP 16500C drive to your computer.

These graphics files contain the current display on the HP 16500C screen. The

contents of the files change whenever you change the display. When you copy

one of the graphics files, the display will freeze for a few moments while the

HP 16500C is copying the current display.

Example

To copy a PCX picture of the current screen display to your computer, enter

the following command at the UNIX command prompt:

$ cp /logic/system/graphics/screen.pcx {local path name}

If you are using a DOS system, you can use the copy command. In the

Microsoft Windows environment, you can use the File Manager.

3–18

Concepts

Understanding how the analyzer does its job will help you use it more

effectively and minimize measurement problems. This chapter

explains the general operation of the trigger sequencer and the

inverse assembler.

4–2

The Trigger Sequencer

Logic state and timing analyzer modules for the HP 16500C have

triggering and data storage features that allow you to capture only the

system activity of interest. Understanding how these features work

will help you set up analyzer trigger specifications that satisfy your

measurement needs.

There are several different logic analyzers available for the

HP 16500C. This discussion will focus on the HP 16550A, a 100-MHz

state/500-MHz timing analyzer. Most HP logic analyzers will be similar,

differing only in the number of available states, pattern resources,

range resources, and acquisition memory depth.

In the HP 16550A state analyzer, the trigger sequencer is a state

machine with a minimum of two states and a maximum of twelve

states. The trigger term can be any one of these states except the last.

The analyzer searches for a trigger sequence by matching input values

on the pods to branch conditions, which control transitions between

states. You can insert or delete states to make the trigger sequence as

simple or complex as needed for your application.

Trigger Sequence Specification

See the following figure, which shows a sequence specification with

four states. To define the trigger sequence, you specify

sequence-advance, sequence-else, storage, and trigger-on

specifications.

4–3

Concepts

A sequence-else specification can

branch to the same state...

Sequence-advance

specifications always

branch to the next state.

to a previous state...

or a later state.

Each state can have a

unique storage

specification.

State Analyzer Sequencer with Four States

Each state, except for the last, has two branch conditions. These are

the sequence-advance and sequence-else specification. (The

trigger-on specification is a special sequence-advance specification

that is described in the section “TRIGGER On Specification.”)

Sequence-Advance Specification

The sequence-advance branch, sometimes called the “if” branch or

primary branch, always branches to the next higher-numbered state.

You can specify the following kinds of sequence-advance

specifications:

Find (or Then find) "<TERM>" <OCCURS> time(S)

Find (or Then find) "<TERM>" <TIME PERIOD>

If the Find (or Then find) “<TERM>” is found <OCCURS> number of

times, the sequencer advances to the next sequence level.

If the <TERM> remains stable for <TIME PERIOD>, the sequencer

advances to the next sequence level.

4–4

Concepts

Sequence-Else Specification

The sequence-else branch, sometimes called the “else if” branch or

secondary branch, may branch to any other state, including the

current state, a previous state, or a later state. The sequence-else

specification looks like the following:

Else on "<TERM>" go to level <sequence level>

If the Sequence-Else specification is satisfied before the

sequence-advance specification is satisfied, the sequencer begins at

<sequence level>.

The last state may only have a sequence-else branch specification,

which may branch to the same state or a prior state.

Storage Specification

In each state, a storage specification determines the data stored by

the analyzer while it is searching for the sequence-advance,

sequence-else, and trigger specifications. Storage specifications are

defined using the same pattern, range, and timer resources available

for defining branching specifications.

While storing "anystate", "no state", or "<TERM>"

Note that if you specify “no state,” the analyzer still stores

sequence-advance terms and TRIGGER terms.

TRIGGER On Specification

If there are branch and storage specifications for each sequence level,

what does the trigger term mean? The trigger term is a special

sequence-advance specification in that, when found, it locks the

contents of analyzer acquisition memory. The trigger can be

positioned at the beginning, middle, or end of acquisition memory.

The trigger specification can look like the following:

TRIGGER on "<TERM>" <OCCURS> times

TRIGGER on "<TERM>" <TIME PERIOD>

If the trigger term is found <OCCURS> times, or if the trigger term

remains stable for <TIME PERIOD>, the trigger is captured in

memory. Then the sequencer advances to the next sequence level. If

4–5

Concepts

you want to capture activity after the trigger is captured, define an

additional sequence level and specify the desired storage qualification

for post-trigger activity (for example, store “anystate”).

Analyzer Resources

The sequence-advance, sequence-else, storage, and trigger-on

specifications are set by a combination of up to 10 pattern terms, 2

range terms, and 2 timers. Different analyzer models may vary in the

number of resources available.

10 Pattern Terms

The pattern terms, a through j, represent single states to be found on

labeled sets of bits. For example, you could have an address on the

address bits or a status on the status bits.

2 Timers

You can start, stop, continue, or pause the timers upon entry to a

sequence state, then use a comparison of current timer value against a

preset value to determine whether to branch to another state.

2 Range Terms

The range terms, Range1 and Range2, represent ranges of values to be

found on labeled sets of bits. For example, you could have a range of

addresses to be found on the address bus or a range of data values to

be found on the data bus. Range terms are satisfied by any value

within the range for “In_Range,” and any value outside the range for

“Out_Range.”

You can combine the pattern terms and range terms with logical

operators to form complex pattern expressions in the

sequence-advance, sequence-else, and TRIGGER on specifications.

For example,

Find "<TERM1>+<TERM2>" OR <TERM1> and <TERM2>

Find "<TERM1>.<TERM2>" AND <TERM1> and <TERM2>

4–6

Concepts

Where <TERM> can be a single value on a set of labels, any value

within a range of values on a set of labels, or a glitch or edge transition

on a bit or set of bits.

Limitations Affecting Use of Analyzer Resources

There are limitations on the way resources can be combined to form

complex pattern expressions. Resources are combined in a four-level

hierarchy. First, resources are divided into two groups. The groups

can be combined with AND or OR. Second, within these groups,

resources are combined into pairs. Pairs can also be logically

combined using AND or OR. Third, individual resources are combined

into pairs using AND, NAND, OR, NOR, XOR, NXOR. Fourth,

individual resources may be included or excluded from participating

in a pattern expression. You can also include the logical negation of

the resource.

The following table shows how resources are divided in the

HP 16550A. Remember that some resources may not be available,

depending on the analyzer configuration. For example, if you are

using the analyzer as a state analyzer, the Edge1 and Edge2 resources

are not available. If the timers are off, the Timer1 and Timer2

resources are not available.

4–7

Concepts

Table 4-1

HP 16550A Resource Division

Group

Pair

Resource Operation

Resource

Pair Links

Group Link

Group

Pair 1

Off, On, Negate

Combine

resources

within

pairs

using

AND,

NAND, OR,

XNOR

Pair 2

Pair 3

Pair 4

Pair 1

Pair 2

Pair 3

Pair 4

Off, In Range, Out of Range Range 1

Off, On, Negate

Off, <, >

Off, On, Negate

Combine

pairs

within

groups or

in group 1

and group

2 using

Edge 1

Timer 1

Group

Combine

resources

within

pairs

using

AND,

NAND, OR,

NOR,

AND or OR

Off, In Range, Out of Range Range 2

Off, On, Negate

Off, <, >

Edge 2

Timer 2

XNOR

So, the following combinations are valid combinations for the state

analyzer, if timers are on:

(a+b) • (In_Range2 + Timer2 > 400 ns)

(c • Out_Range1) + (f xor g)

The following combinations are not valid, because resources cross pair

boundaries:

(a + c)

(d + Timer1 < 400 ns)

The first example shows that a and c cannot be combined at the first

level. You can get around this, however, by combining them at the

second level.

4–8

Concepts

The following figure shows the possible combinations of the a, b, c and

Range1 terms:

Combining a, b, c, and Range1 Terms

The following combination is not valid, because pairs cross group

boundaries:

((a+b) + (h • In_Range2)) • (j xor Timer2 > 400 ns)

Note that the analyzer interface will not allow you to enter invalid

combinations, however, you need to be aware of what combinations

are legal, so that you can make the desired measurement.

Another limitation is that the analyzer cannot handle ranging for input

pods that are assigned to different analysis IC’s. For example, if you

need to define a 32-bit range term, you must do it using pods 1/2, 3/4,

or 5/6. Trying to define a range across pods 2/3, 4/5, or 1/6 will not

work.

The Timing Analyzer

When you configure the HP 16550A as a timing analyzer, the trigger

sequencer is similar. However, there are between 1 and 10 states

available. The trigger term is always the last state. There are two

additional resources, Edge1 and Edge2. These can recognize

occurrences of a glitch, or occurrences of a rising edge, falling edge,

either edge, or no edge on a bit or ORed set of bits represented by a

glitch/edge term.

4–9

The Inverse Assembler

When the analyzer captures a trace, it captures binary information.

The analyzer can then present this information in binary, octal,

decimal, hexadecimal, or ASCII. Or, if given information about the

meaning of the data captured, the analyzer can inverse assemble the

trace. The inverse assembler makes the trace list more readable by

presenting the trace results in terms of processor opcodes and data

transactions.

The inverse assembly software needs five pieces of information:

• Address bus. The inverse assembler expects to see the label ADDR,

with bits ordered in a particular sequence.

• Data bus. The inverse assembler expects to see the label DATA,

with bits ordered in a particular sequence.

• Status. The inverse assembler expects to see the label STAT, with

bits ordered in a particular sequence.

• Start state for disassembly. This is the first displayed state in the

trace list, not the cursor position. See the figure below.

• Tables indicating the meaning of particular status and data

combinations.

When you press the Invasm key to begin inverse assembly of a trace,

the inverse assembler begins with the first displayed state in the trace

list. This is called synchronization. It looks at the status bits (STAT)

and determines the type of processor operation, which is then

displayed under the STAT label. If the operation is an opcode fetch,

the inverse assembler uses the information on the data bus to look up

the corresponding opcode in a table, which is displayed under the

DATA label. If the operation is a data transfer, the data and

corresponding operation are displayed under the DATA label. This

continues for all subsequent states in the trace list.

4–10

Concepts

The inverse assembler

synchronizes at the

first line in the trace

list...

not at the cursor

position

Inverse Assembly Synchronization

If you roll the trace list to a new position and press Invasm again, the

inverse assembler repeats the above process. However, it does not

work backward in the trace list from the starting position. This may

cause differences in the trace list above and below the point where

you synchronized inverse assembly. The best way to ensure correct

inverse assembly is to synchronize using the first state you know to be

the first byte of an opcode fetch.

For processors with a pipeline or instruction queue, the information

presented to the analyzer can potentially become confusing. Was an

instruction executed or not? Active circuitry on some preprocessor

models helps by sorting out the order of execution before presenting

information to the analyzer. You can set switches on the preprocessor

to control whether this dequeueing is enabled.

4–11

Concepts

Symbols

When you specify symbols as the format for displaying the address bus in the

trace list, the symbol lookup happens independently of inverse assembly. Thus,

you can have symbols in the address field without inverse-assembled data and

status. The HP E2450A symbol download utility allows you to download symbols

from OMF (Object Module Format) files.

See Also

The Preprocessor User’s Guide for more information on switch

settings.

Chapter 5, “If You Have a Problem,” if you have problems using the

inverse assembler.

4–12

Configuration Translation for Analyzer Modules

Configuration files provide an easy way for you to save and restore

measurement setups, simplifying repeated measurements. However,

sometimes you might change analyzer modules in the HP 16500C

Logic Analysis System to gain additional measurement features. Or,

you might want to use a configuration file from one HP 16500C system

on another HP 16500C with a different analyzer module. But, the

analyzer configuration files cannot be transferred directly from one

type of analyzer to the next. Each analyzer has internal architectural

differences, reflected in the number of pods, clock configurations,

trigger sequencer features, analyzer resources, and so on.

To help you move configuration files from one analyzer to another,

some analyzer measurement modules for the HP 16500C Logic

Analysis System support automatic translation of analyzer

configurations. If you save an analyzer configuration from one kind of

analyzer module, then load that configuration into a module that

supports configuration translation, the translator will adjust the

configuration as required to account for differences between the

modules.

The configuration translator needs to account for many aspects of the

analyzer architecture. Some of the considerations are as follows:

• For some analyzers, demultiplexing data will require separate

analyzer pods, because a master clock and a slave clock can’t be

assigned on the same pod to perform the demultiplexing. The

translator may display messages on the analyzer screen that ask

you to reconnect pod cables in a different configuration.

• When a range term is split across multiple pods, the term must span

adjacent odd/even pairs, starting with 1. Thus, terms could span

pods 1 and 2, 3 and 4, 5 and 6, or 7 and 8, but not 2 and 3. Again,

the translator may display messages asking you to reconnect cables

in a different configuration.

• When loading a configuration into an analyzer with fewer pods than

the one on which the configuration was saved, the translator must

4–13

Concepts

remove pod assignments. Which pods are removed from the

configuration will depend on the widths of each pod in the original

analyzer and new analyzer.

The configuration translation also needs to account for many

differences in the format and trace menus between the analyzers,

including

• label names,

• polarities,

• thresholds,

• symbols,

• clocking,

• number of sequence levels,

• branch conditions, and

• patterns,

among others.

To ensure that trace measurements act as expected when you move

configuration files from one analyzer to another, follow these

recommendations:

• Ensure that the analyzer pods are hooked up as required by the

configuration translation and the new analyzer. The onscreen

messages given by the translator will help you identify which

analyzer pods must be swapped. If you are using an HP

preprocessor, the Preprocessor User’s Guide may contain

information showing the cable connections for different analyzer

modules.

• Review all trace format and trigger menu settings to verify that they

will meet your measurement requirements. You should check label

assignments, channel masks, pattern and range definitions,

sequencer setup, and general analyzer configuration (which pods

are mapped to each analyzer).

4–14

Concepts

When you move a configuration file from one analyzer to another, the trace data

from previous measurements is not moved. If you need to store trace data for

future reference, see “To save a trace list in ASCII format” in chapter 3.

4–15

4–16

If You Have a Problem

Occasionally, a measurement may not give the expected results. If you

encounter difficulties while making measurements, use this chapter to

guide you through some possible solutions. Each heading lists a

problem you may encounter, along with some possible solutions. Error

messages which may appear on the logic analyzer are listed below in

quotes “ ”. Symptoms are listed without quotes.

If you still have difficulty using the analyzer after trying the

suggestions in this chapter, please contact your local Hewlett-Packard

service center.

When you are working with the analyzer, be sure to power down both the

analyzer and the target system before disconnecting or connecting cables,

probes, and preprocessors. Otherwise, you may damage circuitry in the

analyzer, preprocessor, or target system.

CAUTION

5–2

Analyzer Problems

This section lists general problems that you might encounter while

using the analyzer.

Intermittent data errors

This problem is usually caused by poor connections, incorrect signal levels, or

marginal timing.

Remove and reseat all cables and probes; ensure that there are no bent

pins on the preprocessor interface or poor probe connections.

Adjust the threshold level of the data pod to match the logic levels in the

system under test.

Use an oscilloscope to check the signal integrity of the data lines.

Clock signals for the state analyzer must meet particular pulse shape and

timing requirements. Data inputs for the analyzer must meet pulse shape and

setup and hold time requirements.

See Also

See “Capacitive Loading” in this chapter for information on other sources of

intermittent data errors.

Unwanted triggers

Unwanted triggers can be caused by instructions that were fetched but not

executed.

Add the prefetch queue or pipeline depth to the trigger address to avoid

this problem.

The depth of the prefetch queue depends on the processor that you are

analyzing. Suppose you are analyzing a pipelined processor having fetch,

decode, execute, and memory stages. The processor fetches 32-bit words. To

ensure that the processor has begun executing a particular routine when the

trigger occurs, set the trigger to the module entry address plus 08 hex. (This

assumes that there is no immediate data in the instruction stream.)

5–3

If You Have a Problem

No Setup/Hold field on format screen

The HP 16540 and 16541 (A and D models), or HP 16542A logic analyzer

cards are not calibrated. Refer to your logic analyzer reference manual for

procedures to calibrate the cards.

No activity on activity indicators

On the HP 16510A Logic Analyzer, check the fuse that allows power to

the preprocessor interface.

On other logic analyzers, check for loose cables, board connections, and

preprocessor interface connections.

Check for bent or damaged pins on the preprocessor probe.

Capacitive loading

Excessive capacitive loading can degrade signals, resulting in incorrect

capture by the preprocessor interface, or system lockup in the

microprocessor. All preprocessor interfaces add additional capacitive loading,

as can custom probe fixtures you design for your application.

Careful layout of your target system can minimize loading problems and

result in better margins for your design. This is especially important for

systems that are running at frequencies greater than 50 MHz.

Remove as many pin protectors, extenders, and adapters as possible.

If multiple preprocessor interface solutions are available, try using one

with lower capacitive loading.

See Also

Chapter 6 lists some application notes that discuss the problems of probing

high-speed digital systems.

5–4

If You Have a Problem

No trace list display

If there is no trace list display, it may be that your analysis specification is not

correct for the data you want to capture, or that the trace memory is only

partially filled.

Check your analysis sequencer specification to ensure that it will

capture the events of interest.

Try stopping the analyzer; if the trace list is partially filled, this should

display the contents of trace memory.

5–5

Preprocessor Problems

This section lists problems that you might encounter when using a

preprocessor. If the solutions suggested here do not correct the

problem, you may have a defective preprocessor. Refer to the User’s

Guide for your preprocessor for test procedures. Contact your local

Hewlett-Packard Sales Office if you need further assistance.

Target system will not boot up

If the target system will not boot up after connecting the preprocessor

interface, the microprocessor or the preprocessor interface may not be

installed properly, or they may not be making electrical contact.

Ensure that you are following the correct power-on sequence for the

preprocessor and target system.

1 Power up the analyzer and preprocessor.

2 Power up the target system.

If you power up the target system before you power up the preprocessor,

interface circuitry in the preprocessor may latch up, preventing proper target

system operation.

Verify that the microprocessor and the preprocessor interface are

properly rotated and aligned, so that the index pin on the

microprocessor (such as pin 1 or A1) matches the index pin on the

preprocessor interface.

Verify that the microprocessor and the preprocessor interface are

securely inserted into their respective sockets.

Verify that the logic analyzer cables are in the proper sockets of the

preprocessor interface and are firmly inserted.

Reduce the number of extender sockets.

See Also

“Capacitive Loading” in this chapter.

5–6

If You Have a Problem

Slow clock

If you have the preprocessor interface hooked up and running and observe a

slow clock or no activity from the interface board, the +5 V supply coming

from the analyzer may not be getting to the interface board.

To check the +5 V supply coming from the analyzer, disconnect one of

the logic analyzer cables from the preprocessor and measure across pins

1 and 2 or pins 39 and 40.

If +5 V is not present, check the internal preprocessor fuse or current

limiting circuit on the logic analyzer. For information on checking this fuse

•

or circuit, refer to the Service Guide for your logic analyzer.

If +5 V is present and the cable connection to the preprocessor appears

sound, contact your nearest Hewlett-Packard Sales Office for information

on servicing the board.

•

Erratic trace measurements

There are several general problems that can cause erratic variations in trace

lists and inverse assembly failures.

Ensure that the preprocessor configuration switches are correctly set

for the measurement you are trying to make.

Some preprocessors include configuration switches for various features (for

example, to allow dequeueing of the trace list). See your Preprocessor

User’s Guide for more information.

5–7

If You Have a Problem

Erratic trace measurements

Try doing a full reset of the target system before beginning the

measurement.

Some preprocessor designs require a full reset to ensure correct

configuration.

Ensure that your target system meets the timing requirements of the

processor with the preprocessor probe installed.

See “Capacitive Loading” in this chapter. While preprocessor loading is slight,

pin protectors, extenders, and adapters may increase it to unacceptable

levels. If the target system design has poor timing margins, such loading may

cause incorrect processor functioning, giving erratic trace results.

Ensure that you have sufficient cooling for the preprocessor probe.

Current processors such as the i486, Pentium , and MC68040 generate

substantial heat. This is exacerbated by the active circuitry on the

preprocessor board. You should ensure that you have ambient temperature

conditions and airflow that meet or exceed the requirements of the

microprocessor manufacturer.

5–8

Inverse Assembler Problems

This section lists problems that you might encounter while using the

inverse assembler.

When you obtain incorrect inverse assembly results, it may be unclear

whether the problem is in the preprocessor or in your target system. If

you follow the suggestions in this section to ensure that you are using

the preprocessor and inverse assembler correctly, you can proceed

with confidence in debugging your target system.

No inverse assembly or incorrect inverse assembly

This problem is due to incorrect synchronization, modified configuration,

incorrect connections, or a hardware problem in the target system. A locked

status line can cause incorrect or incomplete inverse assembly.

Verify that the inverse assembler has been synchronized by placing an

opcode at the top of the display (not at the input cursor) and pressing

the Invasm key.

Because the inverse assembler works from the first line of the trace display,

if you jump to the middle of a trace and select Invasm, prior trace states are

not disassembled correctly. If you move to several random places in the trace

list and select Invasm each time, the trace disassembly is only guaranteed to

be correct from the top of the display forward for each selection.

Ensure that each analyzer pod is connected to the correct preprocessor

cable.

There is not always a one-to-one correspondence between analyzer pod

numbers and preprocessor cable numbers. Preprocessors must supply

address (ADDR), data (DATA), and status (STAT) information to the

analyzer in a predefined order, so the cable connections for each

preprocessor are often altered to support that need. Thus, one preprocessor

might require that you connect cable 2 to analyzer pod 2, while another will

require you to connect cable 5 to analyzer pod 2. See the User’s Guide for

your preprocessor for further information.

5–9

If You Have a Problem

Inverse assembler will not load or run

Check the activity indicators for status lines locked in a high or low

state.

Verify that the STAT, DATA, and ADDR format labels have not been

modified from their default values.

These labels must remain as they are configured by the configuration file. Do

not change the names of these labels or the bit assignments within the labels.

Some preprocessors also require other data labels; check your Preprocessor

User’s Guide for more information.

Verify that all microprocessor caches and memory managers have been

disabled.

In most cases, if the microprocessor caches and memory managers remain

enabled you should still get inverse assembly, but it may be incorrect since

some of the execution trace was not visible to the logic analyzer.

Verify that storage qualification has not excluded storage of all the

needed opcodes and operands.

Inverse assembler will not load or run

You need to ensure that you have the correct system software loaded on your

analyzer.

Ensure that the inverse assembler is on the same disk as the

configuration files you are loading.

Configuration files for the state analyzer contain a pointer to the location of

the corresponding inverse assembler. If you delete the inverse assembler or

move it to another location, the configuration process will fail.

Make sure you are using the version of the inverse assembler software

that corresponds to the operating system revision installed on your

analyzer.

See your Preprocessor User’s Guide for details.

5–10

Intermodule Measurement Problems

Some problems occur only when you are trying to make a

measurement involving multiple modules.

An event wasn’t captured by one of the modules

If you are trying to capture an event that occurs very shortly after the event

that arms one of the measurement modules, it may be missed, due to internal

analyzer delays. For example, suppose you set the oscilloscope to trigger

upon receiving a trigger signal from the logic analyzer, because you are trying

to capture a pulse that occurs right after the analyzer’s trigger state. If the

pulse occurs too soon after the analyzer’s trigger state, the oscilloscope will

miss the pulse.

Adjust the skew in the Intermodule menu.

You may be able to specify a skew value that enables the event to be

captured.

Change the trigger specification for modules upstream of the one with

the problem.

If you’re using a logic analyzer to trigger the scope, try specifying a trigger

state one state before the one you are using. This may be more difficult than

working with the skew, because the prior state may occur more often and not

always be related to the event you’re trying to capture with the oscilloscope.

5–11

Messages

This section lists some of the messages that the analyzer displays

when it encounters a problem.

“Default Calibration Factors Loaded” (HP 16540,

16541, and 16542)

The default calibration file for the logic analyzer was loaded. The logic

analyzer must be calibrated when using HP 16540A/D, HP 16541A/D or

HP 16542A cards. Refer to the Logic Analyzer Reference for procedures to

calibrate the master clocking system, and ensure that the “cal factors” file is

saved. Refer to the Logic Analyzer Reference manual for procedures to

calibrate the cards.

“. . . Inverse Assembler Not Found”

This error occurs if you rename or delete the inverse assembler file that is

attached to the configuration file. Ensure that the inverse assembler file is

not renamed or deleted.

5–12

If You Have a Problem

“Measurement Initialization Error”

This error occurs when you have installed the cables incorrectly for one or

two HP 16550A logic analysis cards. The following diagrams show the correct

cable connections for one-card and two-card installations. Ensure that your

cable connections match the drawing, then repeat the measurement.

Cable Connections for One-Card HP 16550A Installations

Cable Connections for Two-Card HP 16550A Installations

See Also

The HP 16550A 100-MHz State/500-MHz Timing Logic Analyzer Service

Guide.

5–13

If You Have a Problem

“No Configuration File Loaded”

This is usually caused by trying to load a configuration file for one type of

module or the system into a different type of module.

Verify that the appropriate module has been selected from the Load

{module} from File {filename} in the HP 16500 disk operation menu.

Selecting Load {All} will cause incorrect operation when loading most

preprocessor interface configuration files.

See Also

“To Load a Configuration File” in chapter 3, “File Management.”

“Selected File is Incompatible”

This occurs when you try to load a configuration file for the wrong module.

Ensure that you are loading the appropriate configuration file for your logic

analyzer.

“Slow or Missing Clock”

This error message might occur if the logic analyzer cards are not firmly

seated in the HP 16500C or HP 16501A frame. Ensure that the cards are

firmly seated.

This error might occur if the target system is not running properly.

Ensure that the target system is on and operating properly.

If the error message persists, check that the logic analyzer pods are

connected to the proper connectors. See the User’s Guide for your

preprocessor interface to determine the proper connections.

For HP 16510A Logic Analyzers, check the preprocessor interface power

fuse in the logic analyzer.

5–14

If You Have a Problem

“State Clock Violates Overdrive Specification”

At least one 16-channel pod in the state analysis measurement stored a

different number of states before trigger than the other pods. This is usually

caused by sending a clocking signal to the state analyzer that does not meet

all of the specified conditions, such as minimum period, minimum pulse

width, or minimum amplitude. Poor pulse shaping could also cause this

problem.

The error message “State Clock Violates Overdrive Specification” should occur

only for HP 16510A/B, and HP 16511B Logic Analyzers with the Clock Period field

set to <60 ns. If this error message is observed with the Clock Period set to >60

ns, you may have a faulty logic analyzer. If a failure is suspected in your logic

analyzer, contact your nearest Hewlett-Packard Sales Office for information on

servicing the instrument.

“Time from Arm Greater Than 41.93 ms”

The state/timing analyzers have a counter to keep track of the time from

when an analyzer is armed to when it triggers. The width and clock rate of

this counter allow it to count for up to 41.93 ms before it overflows. Once the

counter has overflowed, the system does not have the data it needs to

calculate the time between module triggers. The system must know this time

to be able to display data from multiple modules on a single screen.

5–15

If You Have a Problem

“Waiting for Trigger”

If a trigger pattern is specified, this message indicates that the specified

trigger pattern has not occurred. Verify that the triggering pattern is

correctly set.

When analyzing microprocessors that fetch only from long-word aligned

addresses, if the trigger condition is set to look for an opcode fetch at an

address not corresponding to a long-word boundary, the trigger will

never be found.

If a “don’t care” trigger condition is set, this message indicates:

For an HP 16511B Logic Analyzer, only one of the two cards is receiving

its state clock. Refer to “Slow or Missing Clock.”

For an HP 16510A/B Logic Analyzer, the pattern duration is probably set

to less than (<) instead of greater than (>). Since a “don’t care” pattern is

always true, the “less than” condition is never satisfied. Set the trigger

correctly for the measurement that is desired.

5–16

Application Notes

Hewlett-Packard has prepared several application notes and product

notes that show you how to get more out of your HP 16500C Logic

Analysis System. Each note focuses on a particular application or

problem, showing you the components of the problem, the approach

required to solve it, the instrumentation, and the measurement

results.

The following table lists the application notes and product notes

relevant to the HP 16500C Logic Analysis System. To order, contact

your local Hewlett-Packard Sales Office.

Application Notes and Product Notes

Note Number

HP Part Number

Title

Description

Application Note 392-3

5952-3058

VME/VXI Applications: How the

Right Preprocessor Interface

Can Simplify Logic Analysis

Discusses how using a

preprocessor with your logic

analyzer can simplify

measurements common to

aerospace and defense.

Application Note 1210-2

5091-1800E

Understanding and Minimizing

Probing Effects

Discusses probe loading effects

in a digitizing oscilloscope

measurement. Also applys to

logic analyzers.

Application Note 1223

Application Note 1225-2

5091-4121E

5091-5446E

Logic Analyzer Triggering

Applications

Shows a variety of different

triggering examples using the

HP 16550A state/timing analyzer.

Cache Hit or Miss Analysis with

the HP 16542A

Shows how to analyze cache hit

rate using the HP 16520A Pattern

Generator with the HP 16542A

deep memory state and timing

module.

6–2

Application Notes

Note Number

HP Part Number

Title

Description

Application Note 1225-3

5091-5447E

Digital Video Testing with the

HP 16542A

Uses the deep memory of the

HP 16542A with the complex

triggering capabilities of that

module and of the 16550A

state/timing analyzer to capture

and analyze data from a digital

video stream.

Application Note 1244-1

Application Note 1244-2

5962-8620E

5091-8839E

Minimizing Intrusion Effects

When Probing with a Logic

Analyzer

Discusses physical and

electrical considerations for

probing circuits with an analyzer.

Designing a Custom Interface

for a Logic Analyzer Using HP

User-Definable Design Tools

Describes various HP tools for

designing custom hardware and

software interfaces to newer or

less common chips and buses.

Application Note 1261

Application Note 1266-1

5091-8798E

5963-3544E

Timing Charaterization Using the

HP 16517/18A with Intel

PentiumProcessor

Discusses how the timing

characterization of a digital

system can be performed more

efficiently with a high speed

logic analyzer.

Measurement Examples

Intel 80960CA Software Debug

Using a Logic Analyzer and an

In-Circuit Debugger

Explains how to integrate a logic

analyzer with the MRI Debugger

Monitor for the Intel 80960 CA

processor.

Product Note 16522-1

Product Note 54720A-3

5964-6347E

5091-3758E

Digital Verification with the

HP 16522 Pattern Generator

Shows how to use the pattern

generator with the timing

analyzer to do board verification.

Selecting Oscilloscope Probes

for High-Speed Digital Circuit

Measurements

Discusses loading effects of

probes on digital circuitry. Very

relevant to probing for logic

state and timing analysis as well.

6–3

6–4

Glossary

acquisition Denotes one complete

cycle of data gathering by a module.

For example, in the HP 16532 oscillo-

scope, one complete cycle gathers

8000 samples of information and

stores them in acquisition memory.

cancel autoscale The field that al-

lows you to cancel an autoscale

command. This field is particularly

important if you inadvertently select

the Autoscale field when you have

your measurement configuration set.

Automatically scaling your signals at

this point could change your present

configuration.

arm The arm output from a mod-

ule is set false when the module

begins running and is set true when

the module finds its trigger condi-

tion. Other measurement modules

that take the arm signal as an input

are unable to capture data or search

for their triggers until they receive

their arm signal. The arm signal is

usually used to coordinate measure-

ment start between two or more

measurement modules.

cancel run The field that allows

you to cancel making an oscilloscope

run for any reason once you have se-

lected the Run field.

coupling field The field that sets

the input impedance for the signal

applied to oscilloscope channels. For

example, in the HP 16532A, the in-

put coupling can be set to 1

Mohm/DC, 1 Mohm/AC, and 50

ohm/DC.

attenuation factor See probe

field.

autoscale algorithm An algo-

rithm for oscilloscope modules that,

based on the amplitude and period

of the signals found, sets the vertical

sensitivity in volts per division, off-

set, horizontal sweep speed in

seconds per division, trigger level,

and trigger slope for the trigger in-

put. Its purpose is to set up the

system so that two to five cycles of

the input waveform are displayed on

the screen. The waveform is from

the lowest numbered and lettered

channel with a signal.

cross triggering Using inter-

module capabilities to have

measurement modules trigger each

other. For example, you can have an

external instrument arm a logic ana-

lyzer, which subsequently triggers an

oscilloscope when it finds the trigger

state.

delay field The field that sets the

horizontal position of the waveform

on the screen for the oscilloscope

and timing analyzer. Delay time is

measured from the trigger point. It is

measured in seconds, can be viewed

Glossary–1

Glossary

in the Delay field, and is set by using

the knob or the keypad.

glitch A glitch is defined as two or

more transitions crossing the logic

threshold between consecutive tim-

ing analyzer samples.

deskewing To cancel or nullify the

effects of differences between two

different internal delay paths for a

signal. Deskewing is normally done

by routing a single test signal to the

inputs of two different modules, then

adjusting the delay path to one of

the modules so that both modules

recognize the signal at the same

state at the same time.

high The most-positive portion of a

logic signal. In pattern trigger meas-

urements for the oscilloscope, it is

represented by an H in the pattern

selector.

horizontal position See delay

field.

don’t care Signifies that the state

of the signal, high or low, is not rele-

vant to the measurement. That is,

the analyzer will ignore the state of

this signal when determining

whether a match occurs on an input

label. Don’t cares are represented by

the X character in analyzer resource

terms.

horizontal sweep speed In the

oscilloscope, the time value that de-

termines horizontal scaling of the

waveform to be displayed on the

screen. It is measured in seconds per

division and is viewed in the s/Div

field. It is set by using the knob or

the keypad.

immediate mode In the oscillo-

scope, the trigger mode that does

not require a specific trigger condi-

tion (that is, an edge or a pattern).

edge mode In the oscilloscope,

this is the trigger mode that causes a

trigger based on a single channel

edge (either rising or falling).

input field In the oscilloscope, the

field that allows you to select a chan-

nel for vertical scaling.

glitch/edge terms Timing ana-

lyzer resources that allow detection

of transitions on a signal. A

glitch/edge term can be set to detect

a rising edge, falling edge, either

edge, no edge, or glitch (very short

duration pulse) on an input signal.