mc68hc912dg128 Freescale Semiconductor, Inc, mc68hc912dg128 Datasheet - Page 132

• Manufacturer Part Number: mc68hc912dg128
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

EEPROM Memory
Technical Data
132
EELAT — EEPROM Latch Control
EEPGM — Program and Erase Enable
A program or erase operation should follow the sequence below:
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 the desired value, write EELAT
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
Freescale Semiconductor, Inc.
When test mode is not enabled and unless BULKP is set, erasure is
by byte, aligned word, row or bulk.
Read anytime. Write anytime if EEPGM = 0.
BYTE, ROW, ERASE and EELAT bits can be written simultaneously
or in any sequence.
The EEPGM bit can be set only after EELAT has been set. When
EELAT and EEPGM are set simultaneously, EEPGM remains clear
but EELAT is set.
The BULKP, BYTE, ROW, ERASE and EELAT bits cannot be
changed when EEPGM is set. To complete a program or erase, two
successive writes to clear EEPGM and EELAT bits are required
before reading the programmed data. A write to an EEPROM location
has no effect when EEPGM is set. Latched address and data cannot
be modified during program or erase.
For More Information On This Product,
0 = EEPROM set up for normal reads.
1 = EEPROM address and data bus latches set up for
0 = Disables program/erase voltage to EEPROM.
1 = Applies program/erase voltage to EEPROM.
= 1
programming or erasing.
Go to: www.freescale.com
EEPROM Memory
t
PROG
) or erase (
t
MC68HC912DG128 — Rev 3.0
erase
) delay time
MOTOROLA