Advance Information MC68HC908MR16/MC68HC908MR32 — Rev. 4.0
60 FLASH Memory MOTOROLA
FLASH Memory
4.5 FLASH Page Erase Operation
Use this step-by-step procedure to erase a page (128 bytes) of FLASH
memory to read as logic 1:
1. Set the ERASE bit, and clear the MASS bit in the FLASH control
register.
2. Read the FLASH block protect register.
3. Write any data to any FLASH address within the page address
range desired.
4. Wait for a time, tNVS, minimum of 10 µs.
5. Set the HVEN bit.
6. Wait for a time, tErase, minimum of 1 ms.
7. Clear the ERASE bit.
8. Wait for a time, tNVH, minimum of 5 µs.
9. Clear the HVEN bit.
10. After a time, tRCV (typically 1 µs), the memory can be accessed
again in read mode.
NOTE: While these operations must be perfor m ed in the order shown, other
unrelated operations may occur between the steps.