HP 1660CS, User Manual

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To view your target system processing an interrupt
Use the oscilloscope to trigger on the asynchronous interrupt request.
1
Go to the state analyzer’s Trigger menu, and set the analyzer to
trigger on any state and store any state.
2
Select Arming Control. Set the analyzer to respond to the arm signal
from the oscilloscope, and set the oscilloscope to Group Run.
3
Go to the Scope Trigger menu, and set the mode to Edge trigger. Set
the Source field to C1, and probe the interrupt with Channel 1.
4
Press the Run key.
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.
Cross-Arming Trigger Examples
To view your target system processing an interrupt
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