Microchip Technology MPLAB ICE, User Manual

Page: 118 / 192

MPLAB
®
ICE User’s Guide
DS51159B-page 118

2001 Microchip Technology Inc.
6.4 Using Code Coverage
The code coverage feature provides visibility as to what portions of the code
are being accessed (fetched, written or read). This code is highlighted in the
Program Memory window in a color defined in Options>Environment Settings,
Color tab, as Trace Point Text.
Figure 6.15: Program Memory Window - Code Coverage Enabled
This feature works by latching addresses as they appear on the bus. Thus,
instructions that follow two-cycle instructions that modify the program counter
may not have been actually executed.
With code coverage enabled, the next halt encountered by the emulator
(software break point or halt command) will cause ROM locations that have
been fetched to be highlighted in the Program Memory window.
Addresses transferred as a result of a table read (TBLRD) or table write
(TBLWR) will be traced using this method.
Note: Code coverage tags prefetched code, regardless of
whether or not it actually gets executed. Therefore,
not all highlighted code may have been executed.