Debug Manual

Sample Debug Sessions
Debug Manual—421921-003
F-44
Native Program Example
FNL Command
We use the FNL command to find the 32-bit data. The value is 32-bit, so the address
given must be aligned on an even quad byte.
The FNL and FN commands stop the search either at the end of the segment or when
the low-order 17 bits of the address are zero. If the address boundary is reached, it is
only necessary to restart the command with the address. The value to search for will
be the same as for the last search.
Searching for Specific Bit Patterns
We can look for a specific pattern within the 32-bit word, while ignoring the other bits.
In this example, we use the FNL command with a mask to look only for the bit pattern
0x3435 in the second and third byte of the word:
STOP Command
Before we move to the rest of the native program examples, we enter the STOP
command to stop the program.
Additional Breakpoint Options
In the following examples, we demonstrate some variations on the B and BM
commands by running the Example F-3, pTAL Compiled Listing several times.
050,03,00266-FNL Q 0 , '3456'
0008002C: 0x33343536
050,03,00266 (FNL)-
** DEBUG error 51: FNL reached address boundary. To continue, enter the
following address:
0x000A0000
050,03,00266-fnl 0x000A0000
000A22E0: 0x33343536
050,03,00266 (FNL)-
** DEBUG error 52: FNL stopped searching at the following address:
0x000BEFD0
Address not valid
Note. The output addresses for the FNL command are hexadecimal byte addresses.
050,03,00266-FNL q0, 0x00343500 & 0x00ffff00
0008002C: 0x33343536
050,03,00266 (FNL)-