mcf51ac256a Freescale Semiconductor, Inc, mcf51ac256a Datasheet - Page 75

• Manufacturer Part Number: mcf51ac256a
• Description: Mcf51ac Flexis
• Manufacturer: Freescale Semiconductor, Inc

4.4.4.5
The mass erase operation will erase the entire flash array memory using an embedded algorithm.
An example flow to execute the mass erase operation is shown in
write sequence is as follows:
If the flash array memory to be mass erased contains any protected area, the FPVIOL flag in the FSTAT
register will set and the mass erase command will not launch. Once the mass erase command has
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1. Write to an aligned flash block address to start the command write sequence for the mass erase
2. Write the mass erase command, 0x41, to the FCMD register.
3. Clear the FCBEF flag in the FSTAT register by writing a 1 to FCBEF to launch the mass erase
command. The address and data written will be ignored.
command.
Mass Erase Command
Clock Register
Written
Check
Bit Polling for
Command Completion
Check
Command
Buffer Empty Check
Access Error and
Protection Violation
Check
MCF51AC256 ColdFire Integrated Microcontroller Reference Manual, Rev. 5
Read: FCDIV register
Figure 4-13. Example Sector Erase Command Flow
2.
3.
1.
yes
FDIVLD
Write: FCMD register
Sector Erase Command 0x40
Write: FSTAT register
Clear FCBEF 0x80
Write: Flash Sector Address
and Dummy Data
START
Set?
Read: FSTAT register
Read: FSTAT register
FACCERR/FPVIOL
yes
FCBEF
yes
no
FCCF
Set?
Set?
EXIT
Write: FCDIV register
Set?
no
no
yes
no
Write: FSTAT register
Clear FACCERR/FPVIOL 0x30
Note: FCDIV needs to
be set after each reset
Figure
4-14. The mass erase command
Memory
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