Motorola M68HC11EVBD, User Manual

Page: 76 / 110

OPERATING INSTRUCTIONS
4-30 M68HC11EVBU/D
T Trace
4.6.16 Trace
T [<n>]
where:
<n> is the number (in hexadecimal, $1-FF max.) of instructions to execute. A
default value of 1 is used if <n> is not specified.
The T command allows the user to monitor program execution on an instruction-by-instruction
basis. The user may optionally execute several instructions at a time by entering a count value
(up to $FF). Execution starts at the current program counter (PC). Each event message line
includes a disassembly of the instruction that was traced and a register display showing the CPU
state after execution of the traced instruction. The trace command operates by setting the OC5
interrupt to time out after the first cycle of the first user opcode fetched.
NOTE
The RD command was used to set the user PC register to $FF85
prior to starting the following trace examples.
SINGLE TRACE EXAMPLE
>T<CR>
JMP
$E1F7 P-E1F7 Y-FFFF X-FFFF A-44 B-FF C-10 S-0046
>
MULTIPLE TRACE EXAMPLES
>T 2<CR>
PSHA
P-E1F8 Y-FFFF X-FFFF A-44 B-FF C-10 S-0046
PSHB P-E1F9 Y-FFFF X-FFFF A-44 B-FF C-10 S-0045
>T 3<CR>
PSHX
P-E1FA Y-FFFF X-FFFF A-44 B-FF C-10 S-0043
JSR $E19D P-E19D Y-FFFF X-FFFF A-44 B-FF C-10 S-0041
CMPA #$61 P-E19F Y-FFFF X-FFFF A-44 B-FF C-19 S-0041
>T 4<CR>
BLT
$E1A7 P-E1A7 Y-FFFF X-FFFF A-44 B-FF C-19 S-0041
RTS P-E1FD Y-FFFF X-FFFF A-44 B-FF C-19 S-0043
CMPA #$30 P-E1FF Y-FFFF X-FFFF A-44 B-FF C-19 S-0043
BLT $E223 P-E223 Y-FFFF X-FFFF A-44 B-FF C-19 S-0043
>