MC68HC08AZ32A Datasheet, PDF (73/456 Pages) Motorola, Inc – HCMOS Microcontroller Unit

Freescale Semiconductor, Inc.
EEPROM
EEPROM Register Descriptions
EEDIVSECD — EEPROM Divider Security Disable
This bit enables/disables the security feature of the EEDIV registers.
When EEDIV security feature is enabled, the state of the registers
EEDIVH and EEDIVL are locked (including EEDIVSECD bit). The
EEDIVHNVR and EEDIVLNVR non-volatile memory registers are
also protected from being erased/programmed.
1 = EEDIV security feature disabled
0 = EEDIV security feature enabled
EEDIV[10:0] — EEPROM Timebase Prescaler
These prescaler bits store the value of EEDIV which is used as the
divisor to derive a timebase of 35µs from the selected reference clock
source (CGMXCLK or bus block in the CONFIG-2 register) for the
EEPROM related internal timer and circuits. EEDIV[10:0] bits are
readable at any time. They are writable when EELAT = 0 and
EEDIVSECD = 1.
The EEDIV value is calculated by the following formula:
EEDIV= INT[Reference Frequency(Hz) x 35 x10^-6 +0.5]
Where the result inside the bracket is rounded down to the nearest
integer value
For example, if the reference frequency is 4.9152MHz, the EEDIV value
is 172
NOTE: Programming/erasing the EEPROM with an improper EEDIV value may
result in data lost and reduce endurance of the EEPROM device.
MC68HC08AZ32A — Rev 1.0
MOTOROLA
EEPROM
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Technical Data
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