If The Analyzer Triggers On A Program Address When It Should Not; If Trace Disassembly Appears To Be Partially Incorrect - HP MC68040 User Manual

Chapter 9: Solving Problems

If the analyzer triggers on a program address when it should not

If the analyzer triggers on a program address
when it should not
Check to see if the analyzer is triggering on an instruction prefetch. The analyzer
cannot distinguish between prefetch and execution because the processor does not
provide that information. Usually your actual trigger address is within 16 words of
the address where trigger is occurring.
Try to pad the program code with NOP instructions to move the trigger address
away from the other code so that it won't be prefetched until it is time to trigger.
You may be able to insert a write instruction to a meaningless variable in your code
immediately before the trigger address. Then you can trigger on a write to the
address of the meaningless variable. Write transactions never appear in instruction
prefetches.
If trace disassembly appears to be partially
incorrect
Check to see if the analyzer began disassembly of the trace on a long-word
boundary but the instruction started on the low word within the long word. This
will make disassembly incorrect. You can start disassembly on the low word
within the long word by use of display trace disassemble_from_line_number
<trace list line number> low_word.
If the trace list seems correct for a few states after disassembly starts, and then it
seems incorrect, restart disassembly of the trace at the low word where disassembly
first becomes incorrect display trace disassemble_from_line_number <trace list
line number> low_word.
If an instruction seems to have incorrect data associated with it, you can read down
the trace list to see if you can find correct data for the instruction on another line.
You can cause the disassembler to realign the instruction with the correct data by
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