Microchip Technology MPLAB ICE, Руководство пользователя

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2001 Microchip Technology Inc. DS51159B-page 143
Debugging Techniques
Enter the address of the start of the ISR (either a numeric address or a label).
In Figure A.1, the address is
irqsvc
.
If Infinite Events is checked, uncheck it. Then enter the number of Captured
Events, or the number of times you want to capture the start of the ISR to the
Trace Memory Window. In Figure A.1, the Captured Events are 200.
Finally, check Halt on Trace Buffer Full.
Click Apply or OK.
Reset the system (Debug>System Reset) and then run your program
(Debug>Run>Run or green stoplight icon on toolbar). After it halts, bring up
the Trace Memory Window (Window>Trace Memory).
Figure A.2: Trace Display - Filter Trace for ISR Time
Calculate the difference between interrupt starts (Seconds difference). In
Figure A.2, the difference is 132 microseconds.
Solution B: Time Between Events
Another more direct method is to use the Time Between Events (TBE) trigger.
For this trigger type, the time stamp generator is held at zero until a specified
starting event occurs. The time stamp generator then continues to increment
normally until a specified stopping event occurs. The time stamp can then be
used to measure the lapsed time.
To clear all break, trace and trigger points, select Debug>Clear All Points.
Select Debug>Complex Trigger Settings to open the Complex Trigger
Settings dialog.
Set up the Complex Trigger Settings dialog for Time Between Events on
Program Memory. Click on the Start Timer Tab.