Microchip Technology MPLAB ICE, Руководство пользователя

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2001 Microchip Technology Inc. DS51159B-page 117
Advanced Features
6.3.5.5 Filter Trace Example - Data Memory
How do I filter on data memory?
Filtering on PICmicro file register reads and writes will result in the collection
of the cycles immediately following the R/W. While this is not exactly the
information you are looking for, it does provide two data points:
1. The program memory after the R/W occurred, so you can track down
places in your code that affect a particular variable or SFR.
2. The number of times the R/W occurred, providing you with a count of the
collected cycles.
There are two ways to capture the actual data values with a filter. The first is
to filter on the routine that does the R/W. This will generate some extra cycles,
but will collect the proper information. The second is to make code that will
generate two R/W cycles to the same location, one of which does not affect
the actual data. For instance, the register can be ANDed with a value of 0xFF
to generate the extra cycle like this:
test
movlw 0xFF
movwf LSDigit
test1
decfsz LSDigit
andwf LSDigit ; generate extra read/w to LSDigit
goto test1