User`s manual

T - Trace
3-216
3
T - Trace
Command Input
T [COUNT]
Description
The T command executes one instruction at a time, displaying the
target state after execution. T starts tracing at the address in the
target IP.
The optional COUNT argument (which defaults to 1) specifies the
number of instructions to be traced before returning control to the
debugger.
Breakpoints are monitored (but not inserted) during tracing for all
trace commands. Instruction memory must be writable. In all cases,
if a breakpoint with 0 count is encountered, control is returned to
the debugger.
The trace functions are implemented by inserting traps in the code.
Therefore, the code must be writable and uncached for tracing to be
effective.
Example
The following program resides at location $30000, and breakpoint
is specified at location $30014.
PPC1-Bug>DS 30000 <Return>
00030000 3CA00000 ADDIS R5,R0,$0
00030004 2B040000 CMPLI CRF6,0,R4,$0
00030008 419A0014 BC 12,26,$0003001C
0003000C 98A30000 STB R5,$0(R3) ($00041000)
00030010 3884FFFF ADDI R4,R4,$FFFFFFFF
00030014 38630001 ADDI R3,R3,$1
00030018 4BFFFFEC B $00030004
0003001C 4E800020 BCLR 20,0
PPC1-Bug>