Block Guide — S12EETX4KV0 V00.04
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2. Write the sector modify command, $60, 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.

Figure 4-7 Example Sector Modify Command Flow

4.1.4 Illegal EEPROM Operations

The ACCERR flag will be set during the command write sequence if anyof the following illegal steps are

performed, causing the command write sequence to immediately abort:

Write: EEPROM Word Address
Write: ECMD register
Sector Modify Command $60
Write: ESTAT register
Clear CBEIF $80
1.
2.
3.
Clear ACCERR/PVIOL $30
Write: ESTAT register
yes
no
Access Error and
Protection Violation
and program Data
Read: ESTAT register
NOTE: command write sequence
aborted by writing $00 to
ESTAT register.
NOTE: command write sequence
aborted by writing $00 to
ESTAT register.
Read: ESTAT register
no
START
yes
Check
CBEIF
Set?
Address, Data,
Command
Buffer Empty Check
ACCERR/
PVIOL
Set?
EXIT
Write: ECLKDIV register
Read: ECLKDIV register
yes
no
Clock Register
Written
Check
EDIVLD
Set? NOTE: ECLKDIV needs to
be set once after each reset.
no
Bit Polling for
Command Completion
Check
yes
CCIF
Set?

Freescale Semiconductor, I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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