mc68hc08az60 Freescale Semiconductor, Inc, mc68hc08az60 Datasheet - Page 55

• Manufacturer Part Number: mc68hc08az60
• Description: M68hc08 Family Of 8-bit Microcontroller Units Mcus
• Manufacturer: Freescale Semiconductor, Inc

Functional Description
EEPROM
Programming
3-eeprom-2
MOTOROLA
The 512 bytes of EEPROM-2 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 nonvolatile block
protection option. These options are stored in the EEPROM nonvolatile
register (EENVR2) and are loaded into the EEPROM array configuration
register after reset (EEACR2) or a read of EENVR2. Hardware interlocks
are provided to protect stored data corruption from accidental
programming/erasing.
The EEPROM-2 array will leave the factory in the erased state: all
addresses logic ‘1’ and bit 4 of the EENVR2 register programmed to ‘1’
such that the full array is available and unprotected.
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
EENVR2 can be programmed. It is recommended that all bits should
be erased before being programmed.
Follow this procedure to program a byte of EEPROM after first ensuring
the block protect feature is not set on the address block of the byte to be
programmed:
1. Clear EERAS1 and EERAS0 and set EELAT in the EECR2. (See
2. Write the desired data to any user EEPROM address.
3. Set the EEPGM bit. (See note C.)
4. Wait for a time, t
5. Clear EEPGM bit.
6. Wait for a time, t
7. Clear EELAT bits. (See note D.)
8. Repeat steps 1 to 7 for more EEPROM programming.
Freescale Semiconductor, Inc.
For More Information On This Product,
note A and B.)
Go to: www.freescale.com
EEPROM-2
EEPGM
EEFPV
, for the programming voltage to fall.
, to program the byte.
MC68HC08AZ60 — Rev 1.0
Functional Description
EEPROM-2
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