MC68HC08AS32 Datasheet, PDF (64/394 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

Electrically Erasable Programmable ROM
6.3 Features
EEPROM features include:
• Byte, block, or bulk erasable
• Non-volatile redundant array option
• Non-volatile block protection option
• Non-volatile MCU configuration bits
• On-chip charge pump for programming/erasing
6.4 Functional Description
Addresses $0800–$09FF are EEPROM locations. The 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 in the
non-redundant mode. Reliability (data retention) is further extended if
the redundancy option is selected. EEPROM cells are protected with a
non-volatile, 128-byte, block protection option. These options are stored
in the EEPROM non-volatile register (EENVR) and are loaded into the
EEPROM array configuration register (EEACR) after reset or a read of
EENVR. The EEPROM array also can be disabled to reduce current.
6.4.1 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. When the array is configured in the
redundant mode, programming the first 256 bytes ($0800–$08FF) will
also program the last 256 bytes ($0900–$09FF) with the same data.
Programming the EEPROM in the non-redundant mode is
recommended. Program the data to both locations before entering the
redundant mode.
Advance Information
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MC68HC08AS32 — Rev. 3.0
Electrically Erasable Programmable ROM (EEPROM)
MOTOROLA