Motorola M68EVB912B32, User Manual

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OPERATION
68EVB912B32UM/D 3-48
T Trace T
syntax:
T [<Count>]
where:
<Count> is an optional 8-bit decimal number in the range 1 to 255.
The Trace command is used to execute one or more user program instructions beginning at the
current Program Counter (PC) location. As each program instruction is executed, the CPU12’s
register contents are displayed and the next instruction to be executed is displayed. A single
instruction may be executed by entering the trace command immediately followed by a carriage
return.
restrictions:
Because of the method used to execute a single instruction, branch instructions (Bcc, LBcc,
BRSET, BRCLR, DBEQ/NE, IBEQ/NE, TBEQ/NE) that contain an offset that branches back to
the instruction opcode DO NOT execute. D-Bug12 appears to become stuck at the branch
instruction and does not execute the instruction even if the condition for the branch instruction is
satisfied. This limitation can be overcome by using the GT (Go Till) command to set a
temporary breakpoint at the instruction following the branch instruction.
In EVB mode, the Trace command may only be used for code located in alterable memory.
These restrictions do not apply when using D-Bug12 on a target system in POD mode.