Flash Memory Array and Control
Freescale Semiconductor
12-35
PXR40 Microcontroller Reference Manual, Rev. 1
Figure 12-18. Erase Sequence
12.3.6
Flash
Shadow Block
The flash shadow block is a memory-mapped block in the flash memory map. Program and erase of the
shadow block are enabled when FLASH_x_MCR[PEAS] = 1 only. After the user has begun an erase
operation on the shadow block, the operation cannot be suspended to program the main address space and
vice-versa. The user must terminate the shadow erase operation to program or erase the main address
space.
User mode read state
Write MCR
ERS
=
1
Select blocks
Erase interlock write
Step 1
Step 2
Step 3
Write MCR
EHV
=
1
High voltage active
Access MCR
DONE
?
Step 4
WRITE
ESUS
=
1
Read MCR
DONE
=
1
Erase suspend
ERS
=
0
User mode read state
PEG
=
0
Read MCR
DONE
=
1
DONE
=
0
Write MCR
ESUS
=
0
EHV
=
1
Abort
WRITE
EHV
=
0
Step 5
Step 6
PEG
?
Success
PEG
=
1
Write MCR
Failure
PEG
=
0
Step 7
EHV
=
0
Erase
more blocks
Step 8
?
No
Yes
Write MCR
ERS
=
0
User mode read state
Step 9
EHV
=
0
Write MCR
PGM
=
1
Program,
Step 2
Go to
Step 2
Note: PEG will remain valid under this
condition until EHV is set high or
ERS is cleared.
Note: ESUS cannot be cleared while
EHV
=
0. ESUS and EHV cannot
be changed in a single
write operation.
PEG Valid Period
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
Page 40: ...PXR40 Microcontroller Reference Manual Rev 1 xl Freescale Semiconductor...
Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
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