Specifications

Wind River Trace for Wind River Workbench

Hardware Reference, 3.0

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One Trace Around (TC)

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One To Four Trace Trigger (TR)

4.3.2 Filtered Trace Limitations For Wind River Trace With ColdFire Processors

ColdFire processors do not have a unique trace event PST[0:3] encoding to indicate

a trace event has occurred. So in order to generate a trace event, Wind River Trace

uses the ColdFire debug exception with a WDDATA instruction to generate a

NOTE: When using both a Trace On (TE) and Trace Off (TD), the processor must

execute the instruction at the Trace On address before the instruction at the Trace

Off address. This is because the Wind River Trace module will treat the first trace

event it encounters as the Trace On event.

If the code to trace contains a loop, then both the Trace On and Trace Off instruction

addresses must be in the loop and the processor must execute the Trace On

followed by the Trace Off every time it loops. If the Trace On code executes more

than once before the next Trace Off code executes, you will not be able to get a valid

trace. Similarly, if the Trace Off code executes more than once before the next Trace

On code executes, you will not be able to get a valid trace.

When tracing a small amount of instructions (less than 32) the Trace On and Trace

Off may not work. If this does occur, use the Trace Around with an After Trace (

AT)

Counter value set.

NOTE: (AMCC 405 and 440 processors only): When any trace event is set using

internal hardware breakpoints, the internal and external debug modes are

disabled (DBCR0[IDM,EDM] = 0). As a result, the software breakpoints cannot be

used. Any attempt to set a software breakpoint will be ignored. Also, if a normal

internal hardware breakpoint is set to halt the target, it will not cause the target to

stop.

NOTE: When performing a filtered trace, do not refresh the Trace view while the

target is running. If the Trace view is refreshed while the target is running, the trace

capture will be temporarily halted. After refreshing, the trace capture will resume.

During the time the trace capture was halted, the condition that caused the trace to

either toggle on or toggle off may have changed, because the target is still running.

However, the trace capture will continue from its original state before it was

temporarily halted; this may no longer be valid, and may result in an invalid trace

being displayed.