MC68HC08AZ0 Datasheet, PDF (59/444 Pages) Motorola, Inc – Advance Information

Freescale Semiconductor, Inc.
EEPROM
Functional description
Functional description
512 bytes of EEPROM can be programmed or erased without an
external voltage supply. The EEPROM has a lifetime of 10,000
write-erase cycles. EEPROM cells are protected with a non-volatile
block protection option. These options are stored in the EEPROM
non-volatile register (EENVR) and are loaded into the EEPROM array
configuration register after reset (EEACR) or after a read of EENVR.
Hardware interlocks are provided to protect stored data corruption from
accidental programming/erasing.
The EEPROM array will leave the factory in the erased state all
addresses logic ‘1’, and bit 4 of the EENVR register will be programmed
to #1 such that the full array is available and unprotected.
EEPROM
programming
The unprogrammed state is a logic ‘1’. Programming changes the state
to a logic ‘0’. Only valid EEPROM bytes in the non-protected blocks and
EENVR can be programmed.
It is recommended that all bits should be erased before being
programmed.
The following procedure describes how to program a byte of EEPROM:
1. Clear EERAS1 and EERAS0 and set EELAT in the EECR
(See Note a. and b.)
2. Write the desired data to any user EEPROM address.
3. Set the EEPGM bit. (See Note c.)
4. Wait for a time, t_EEPGM, to program the byte.
5. Clear EEPGM bit.
6. Wait for the programming voltage time to fall (t_EEFPV).
7. Clear EELAT bits. (See Note d.)
8. Repeat steps 1 to 7 for more EEPROM programming.
3-eeprom
MOTOROLA
EEPROM
For More Information On This Product,
Go to: www.freescale.com
MC68HC08AZ0
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