MC908KX2MDWE Datasheet, PDF (33/210 Pages) Freescale Semiconductor, Inc – High-performance M68HC08 architecture, Fully upward-compatible object code with M6805, M146805, and M68HC05 Families

FLASH Mass Erase Operation
2.8 FLASH Mass Erase Operation
Use the following procedure to erase the entire FLASH memory to read as a 1:
1. Set both the ERASE bit and the MASS bit in the FLASH control register.
2. Read the FLASH block protect register.
3. Write any data to any FLASH address⁽¹⁾ within the FLASH memory address range.
4. Wait for a time, t_NVS (minimum 10 µs).
5. Set the HVEN bit.
6. Wait for a time, t_MErase (minimum 4 ms).
7. Clear the ERASE and MASS bits.
NOTE
Mass erase is disabled whenever any block is protected (FLBPR does not
equal $FF).
8. Wait for a time, t_NVHL (minimum 100 µs).
9. Clear the HVEN bit.
10. After time, t_RCV (typical 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.
1. When in monitor mode, with security sequence failed (see 16.3.2 Security), write to the FLASH block protect register in-
stead of any FLASH address.
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 Data Sheet, Rev. 2.1
Freescale Semiconductor
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