Bus State Analysis
MMDS0508OM/D
88
Bus State Analysis
MOTOROLA
Viewing Data
To view bus analyzer data, press the F4 function key from the debug
screen; this key brings up the bus state analyzer data screen (
Figure
12
). The word loading flashes in the upper right corner of the screen as
the software loads trace-buffer contents into the host computer. The
data is not fully visible until loading is done (loading stops flashing),
although cycles immediately preceding and following the trigger cycle
become valid early during loading.
NOTE:
Be sure to use the highest possible baud rate. If you use a lower baud
rate, it can take several minutes to load trace-buffer data into the host
computer.
The data screen displays trace buffer contents as raw bus cycles, as
disassembled instructions, as mixed instructions and raw bus cycles, or
as source code. In the mixed display, the associated raw bus cycles
follow each disassembled instruction. Press the F4 key repeatedly to
change the display from one form to another.
Table 11
explains other
key commands for the data screen.
If the data capture mode was sequential, the data screen includes a
trigger indicator ( <T> ). This screen indicator separates the pre-trigger
and post-trigger cycles.
The F1 and F2 keys mark cycles <1> and <2>, respectively. The bus
state analyzer uses these marked cycles in time-tag difference
calculations and logging. The software displays the time tag difference,
∆
c, in the lower right corner of the screen. (An R, by the
∆
c value,
indicates a rollover of the time tag value between the occurrence of
cycles <1> and <2>.)
If a log file is open, you can save bus state analyzer data to the log file.
The system logs the information in the selected view mode. While
logging is under way, the SHOWTRIGGER, NEXTA, NEXTB, NEXTC,
NEXTD, and NEXTE commands log trace buffer cycles. To copy the
current data screen to the log file, use the Alt-S key command. Use the
Alt-P key command to log from the <1> cycle to the <2> cycle.
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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