MC68HC908AZ32ACFU MOTOROLA [Motorola, Inc], MC68HC908AZ32ACFU Datasheet - Page 79

• Manufacturer Part Number: MC68HC908AZ32ACFU
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

5.5.3 EEPROM Program/Erase Protection
68HC908AZ32A — Rev 0.0
MOTOROLA
NOTE:
As the CGMXCLK or bus clock is user selected, the EEPROM Timebase
Divider Register must be configured with the appropriate value to obtain
the 35 s. The timebase divider value is calculated by using the following
formula:
This value is written to the EEPROM Timebase Divider Register
(EEDIVH and EEDIVL) or programmed into the EEPROM Timebase
Divider Non-Volatile Register prior to any EEPROM program or erase
operations(see EEPROM Configuration on page 78 and
Timebase Requirements
The EEPROM has a special feature that designates the 16 bytes of
addresses from $08F0 to $08FF to be permanently secured. This
program/erase protect option is enabled by programming the EEPRTCT
bit in the EEPROM Non-Volatile Register (EENVR) to a logic zero.
Once the EEPRTCT bit is programmed to 0 for the first time:
Once armed, the protect option is permanently enabled. As a
consequence, all functions in the EENVR will remain in the state they
were in immediately before the security was enabled.
Freescale Semiconductor, Inc.
EEDIV= INT[Reference Frequency(Hz) x 35 x10
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For More Information On This Product,
Programming and erasing of secured locations $08F0 to $08FF is
permanently disabled.
Secured locations $08F0 to $08FF can be read as normal.
Programming and erasing of EENVR is permanently disabled.
Bulk and Block Erase operations are disabled for the unprotected
locations $0800-$08EF, $0900-$09FF.
Single byte program and erase operations are still available for
locations $0800-$08EF and $0900-$09FF for all bytes that are not
protected by the EEPROM Block Protect EEBPx bits (see
EEPROM Block Protection
Configuration Register
Go to: www.freescale.com
EEPROM
on page 78).
on page 87)
on page 80 and
-6
EEPROM Array
Functional Description
+0.5]
Advance Information
EEPROM
EEPROM
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