S912XHZ512F1VAG Datasheet, PDF (202/978 Pages) Freescale Semiconductor, Inc – Covers MC9S12XHZ384, MC9S12XHZ256

Chapter 4 4 Kbyte EEPROM Module (S12XEETX4KV2)
4.4.2.6 Sector Modify Command
The sector modify operation will erase both words in a sector of EEPROM memory followed by a
reprogram of the addressed word using an embedded algorithm.
An example flow to execute the sector modify operation is shown in Figure 4-23. The sector modify
command write sequence is as follows:
1. Write to an EEPROM memory address to start the command write sequence for the sector modify
command. The EEPROM address written determines the sector to be erased and word to be
reprogrammed while byte address bit 0 is ignored.
2. Write the sector modify command, 0x60, to the ECMD register.
3. Clear the CBEIF flag in the ESTAT register by writing a 1 to CBEIF to launch the sector erase
command.
If an EEPROM sector to be modified is in a protected area of the EEPROM memory, the PVIOL flag in
the ESTAT register will set and the sector modify command will not launch. Once the sector modify
command has successfully launched, the CCIF flag in the ESTAT register will set after the sector modify
operation has completed unless a new command write sequence has been buffered.
MC9S12XHZ512 Data Sheet, Rev. 1.06
202
Freescale Semiconductor