Datasheet

Functional Description
MC68HC908AZ60A • MC68HC908AS60A • MC68HC908AS60E Data Sheet, Rev. 6
Freescale Semiconductor 157
14.3.5 Commands
The monitor ROM uses these commands:
• READ, read memory
• WRITE, write memory
• IREAD, indexed read
• IWRITE, indexed write
• READSP, read stack pointer
• RUN, run user program
A sequence of IREAD or IWRITE commands can access a block of memory sequentially over the full
64-Kbyte memory map.
Table 14-3. READ (Read Memory) Command
Description Read byte from memory
Operand Specifies 2-byte address in high byte:low byte order
Data Returned Returns contents of specified address
Opcode $4A
Command Sequence
Table 14-4. WRITE (Write Memory) Command
Description Write byte to memory
Operand Specifies 2-byte address in high byte:low byte order; low byte followed by data byte
Data Returned None
Opcode $49
Command Sequence
ADDR. HIGHREADREAD ADDR. HIGH ADDR. LOW ADDR. LOW DATA
ECHO
SENT TO
MONITOR
RESULT
ADDR. HIGHWRITEWRITE ADDR. HIGH ADDR. LOW ADDR. LOW DATA
ECHO
SENT TO
MONITOR
DATA