MC68HC908MR8 Datasheet, PDF (59/372 Pages) Motorola, Inc – Microcontrollers

FLASH Memory
Introduction
4.2.4 FLASH Mass Erase Operation
Use this step-by-step procedure to erase the entire FLASH memory to
read as logic 1:
1. Set the ERASE bit and the MASS bit in the FLASH control register.
2. Read the block protect register.
3. Write to any FLASH address with any data within the page
address range desired.
4. Wait for a time, t_NVS (minimum of 10 µs).
5. Set the HVEN bit.
6. Wait for a time, t_Erase (minimum of 4 ms).
7. Clear the ERASE bit.
8. Wait for a time, t_NVHL (minimum of 100 µs).
9. Clear the HVEN bit.
10. After a time, t_RCV (typically 1 µs), the memory can be accessed in
read mode again.
NOTE:
Programming and erasing of FLASH locations cannot be performed by
code being executed from the FLASH memory. While these operations
must be performed in the order shown, other unrelated operations may
occur between the steps. Do not exceed t_NVH maximum. See 21.7
Memory Characteristics.
4.2.5 FLASH Program/Read Operation
Programming of the FLASH memory is done on a row basis. A row
consists of 32 consecutive bytes starting from address $XX00, $XX20,
$XX40, and $XX80.
Use this step-by-step procedure to program a row of FLASH memory:
1. Set the PGM bit in the FLASH control register. This configures the
memory for program operation and enables the latching of
address and data programming.
2. Read the block protect register.
3. Write to any FLASH address with any data within the page
MC68HC908MR8 — Rev 4.1
Freescale Semiconductor
FLASH Memory
Technical Data
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