MC68HC908AP64_07 FREESCALE [Freescale Semiconductor, Inc], MC68HC908AP64_07 Datasheet - Page 121

• Manufacturer Part Number: MC68HC908AP64_07
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

8.3.5 Commands
The monitor ROM firmware uses these commands:
The monitor ROM firmware echoes each received byte back to the PTA0 pin for error checking. An 11-bit
delay at the end of each command allows the host to send a break character to cancel the command. A
delay of two bit times occurs before each echo and before READ, IREAD, or READSP data is returned.
The data returned by a read command appears after the echo of the last byte of the command.
A brief description of each monitor mode command is given in
Freescale Semiconductor
•
•
•
•
•
•
READ (read memory)
WRITE (write memory)
IREAD (indexed read)
IWRITE (indexed write)
READSP (read stack pointer)
RUN (run user program)
3
FROM HOST
ECHO
Notes:
ECHO
Notes:
4
WRITE
1 = Echo delay, 2 bit times
2 = Cancel command delay, 11 bit times
3 = Wait 1 bit time before sending next byte.
FROM HOST
1 = Echo delay, 2 bit times
2 = Data return delay, 2 bit times
3 = Cancel command delay, 11 bit times
4 = Wait 1 bit time before sending next byte.
READ
Wait one bit time after each echo before sending the next byte.
1
1
WRITE
READ
3
ADDRESS
4
HIGH
MC68HC908AP Family Data Sheet, Rev. 4
ADDRESS
HIGH
Figure 8-5. Read Transaction
Figure 8-6. Write Transaction
1
ADDRESS
1
HIGH
ADDRESS
HIGH
3
ADDRESS
NOTE
4
LOW
ADDRESS
LOW
1
ADDRESS
1
LOW
ADDRESS
LOW
Table 8-4
3
DATA
3, 2
1
through
DATA
DATA
Table
RETURN
4
Functional Description
2, 3
8-9.
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