MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 443

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

22.2.2.3 EEPROM AUTO programming & erasing
22.2.2.4 EEPROM Selective Write More Zeros
22.2.3 STOP mode
MC68HC912DT128A — Rev 4.0
MOTOROLA
to be set by programming an 10-bit time base pre-scalar into bits spread
over two new registers, EEDIVH and EEDIVL.
The EEDIVH and EEDIVL registers are volatile. However, they are
loaded upon reset by the contents of the non-volatile SHADOW word
much in the same way as the EEPROM module control register
(EEMCR) bits interact with the SHADOW word for configuration control
on the existing revision.
The second major change to the EEPROM is the inclusion in the
EEPROM control register (EEPROG) of an AUTO function using the
previously unused bit 5 of this register.
The AUTO function enables the logic of the MCU to automatically use
the optimum programming or erasing time for the EEPROM. If using
AUTO, the user does not need to wait for the normal minimum specified
programming or erasing time. After setting the EEPGM bit as normal the
user just has to poll that bit again, waiting for the MCU to clear it
indicating that programming or erasing is complete.
For some applications it may be advantageous to track more than 10k
events with a single byte of EEPROM by programming one bit at a time.
For that purpose, a special selective bit programming technique is
available.
When this technique is utilized, a program / erase cycle is defined as
multiple writes (up to eight) to a unique location followed by a single
erase sequence.
This new version will correctly exit STOP mode without having to
synchronize the start of STOP with the RTI clock.
Appendix: Changes from MC68HC912DG128
Significant changes from the MC68HC912DG128 (non-suffix device)
Appendix: Changes from MC68HC912DG128
Technical Data
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