MC68HC08AZ32A Datasheet, PDF (60/456 Pages) Motorola, Inc – HCMOS Microcontroller Unit

EEPROM
Freescale Semiconductor, Inc.
5.5 Functional Description
The 512 bytes of EEPROM are located at $0800-$09FF and can be
programmed or erased without an additional external high voltage
supply. The program and erase operations are enabled through the use
of an internal charge pump. For each byte of EEPROM, the write/erase
endurance is 10,000 cycles.
5.5.1 EEPROM Configuration
The 8-bit EEPROM Non-Volatile Register (EENVR) and the 16-bit
EEPROM Timebase Divider Non-Volatile Register (EEDIVNVR) contain
the default settings for the following EEPROM configurations:
• EEPROM Timebase Reference
• EEPROM Program/Erase Protection
• EEPROM Block Protection
EENVR and EEDIVNVR are non-volatile EEPROM registers. They are
programmed and erased in the same way as EEPROM bytes. The
contents of these registers are loaded into their respective volatile
registers during a MCU reset. The values in these read/write volatile
registers define the EEPROM configurations.
For EENVR, the corresponding volatile register is the EEPROM Array
Configuration Register (EEACR). For the EEDIVNVR (two 8-bit
registers: EEDIVHNVR and EEDIVLNVR), the corresponding volatile
register is the EEPROM Divider Register (EEDIV: EEDIVH and EE
DIVL).
5.5.2 EEPROM Timebase Requirements
A 35µs timebase is required by the EEPROM control circuit for program
and erase of EEPROM content. This timebase is derived from dividing
the CGMXCLK or bus clock (selected by EEDIVCLK bit in Mask Option
Register B) using a timebase divider circuit controlled by the 16-bit
EEPROM Timebase Divider EEDIV Register (EEDIVH and EEDIVL).
Technical Data
60
MC68HC08AZ32A — Rev 1.0
EEPROM
For More Information On This Product,
Go to: www.freescale.com
MOTOROLA