MC908JB16DWE Datasheet, PDF (134/332 Pages) Freescale Semiconductor, Inc – Microcontrollers

Monitor ROM (MON)
Technical Data
134
Table 9-9. RUN (Run User Program) Command
Description Executes RTI instruction
Operand None
Data
Returned
None
Opcode $28
Command Sequence
SENT TO
MONITOR
RUN
RUN
ECHO
The MCU executes the SWI and PSHH instructions when it enters
monitor mode. The RUN command tells the MCU to execute the PULH
and RTI instructions. Before sending the RUN command, the host can
modify the stacked CPU registers to prepare to run the host program.
The READSP command returns the incremented stack pointer value,
SP + 1. The high and low bytes of the program counter are at addresses
SP + 5 and SP + 6.
SP
HIGH BYTE OF INDEX REGISTER SP + 1
CONDITION CODE REGISTER SP + 2
ACCUMULATOR
SP + 3
LOW BYTE OF INDEX REGISTER SP + 4
HIGH BYTE OF PROGRAM COUNTER SP + 5
LOW BYTE OF PROGRAM COUNTER SP + 6
SP + 7
Figure 9-7. Stack Pointer at Monitor Mode Entry
Monitor ROM (MON)
MC68HC908JB16 — Rev. 1.1
Freescale Semiconductor