MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 133

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

9.6 Program/Erase Operation
MC68HC912DT128A — Rev 4.0
MOTOROLA
CAUTION:
A program or erase operation should follow the sequence below if AUTO
bit is clear:
If the AUTO bit is set, steps 4 and 5 can be replaced by a step to poll the
EEPGM bit until it is cleared.
The state machine will not start if an attempt is made to program or erase
a protected location and therefore the EEPGM bit will never clear on that
EEPROM operation. Check for protected status or use a software
timeout to avoid a continuous loop whilst polling the EEPGM bit. If using
a timeout, ensure steps 5 and 6 are still executed.
It is possible to program/erase more bytes or words without intermediate
EEPROM reads, by jumping from step 5 to step 2.
1. Write BYTE, ROW and ERASE to desired value, write EELAT = 1
2. Write a byte or an aligned word to an EEPROM address
3. Write EEPGM = 1
4. Wait for programming,
5. Write EEPGM = 0
6. Write EELAT = 0
EEPROM Memory
t
PROG
or erase,
t
ERASE
delay time
Program/Erase Operation
EEPROM Memory
Technical Data
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