MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 442

• 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]

Appendix: Changes from MC68HC912DG128
22.2.1.3 Flash Programming Procedure
22.2.1.4 Flash Programming Time
22.2.1.5 Flash External Programming Voltage
22.2.2 EEPROM
22.2.2.1 EEPROM Architecture
22.2.2.2 EEPROM Clock Source and Pre-scaler
Technical Data
442
Programming of the flash is greatly simplified over previous HC12s. The
read / verify / re-pulse programming algorithm is replaced by a much
simpler method.
The most significant change resulting from the new flash technology is
that the bulk erase and program times are now fixed. The erase time is
at least twice as fast while the word programming time is at least 20%
faster.
The new flash does not require an external high voltage supply. All
voltages required for programming and erase are now generated
internally. Pin 97 that was the VFP pin on the 68HC912DG128 is now a
factory TEST pin. On ealy production devices it is recommended that
this pin is not connected within the application, but it may be connected
to VSS or 5.5V max without issue.
Like the flash, the EEPROM is also made from this new NVM
technology. The architecture and basic programming and erase
operations are unchanged. However, there is a new optional
programming method that allows faster programming of the EEPROM.
The first major difference on the new EEPROM is that it requires a
constant time base source to ensure secure programming and erase
operations. The clock source that is going to drive the clock divider input
is the external clock input, EXTALi. The divide ratio from this source has
Appendix: Changes from MC68HC912DG128
MC68HC912DT128A — Rev 4.0
MOTOROLA