ColdFire Flash Module (CFM)
MCF52235 ColdFire® Integrated Microcontroller Reference Manual, Rev. 6
17-4
Freescale Semiconductor
17.3.2
Flash Base Address Register (FLASHBAR)
The configuration information in the flash base address register (FLASHBAR) controls the operation of
the flash module.
•
The FLASHBAR holds the base address of the flash. The MOVEC instruction provides write-only
access to this register.
•
The FLASHBAR can be read or written from the debug module in a similar manner.
•
All undefined bits in the register are reserved. These bits are ignored during writes to the
FLASHBAR, and return zeroes when read from the debug module.
•
The FLASHBAR valid bit is programmed according to the chip mode selected at reset (see
Chapter 12, “Chip Configuration Module (CCM)
” for more details). All other bits are unaffected.
The FLASHBAR register contains several control fields. These fields are shown in
NOTE
The default value of the FLASHBAR is determined by the chip
configuration selected at reset (see
Chapter 12, “Chip Configuration
” for more information).
NOTE
Flash accesses (reads/writes) by a bus master other than the core, DMA
controller, or writes to flash by the core during programming must use the
backdoor flash address of IPSBAR plus an offset of 0x0400_0000. For
example, for a DMA transfer from the first location of flash when IPSBAR
remains at its default location of 0x4000_0000, the source register would be
loaded with 0x4400_0000. Backdoor access to flash for reads can be made
by the bus master, but it takes 2 cycles longer than a direct read of the flash
if using its FLASHBAR address.
Table 17-1. CFM Configuration Field
Address Offset
(from PROGRAM_ARRAY_BASE)
Size
(bytes)
Description
Factory
Default
0x0400 - 0x0407
8
Backdoor Comparison Key
0xFFFF_FFFF_FFFF_FFFF
0x0408 - 0x040B
4
Flash Protection Bytes
(see
”)
0xFFFF_FFFF
0x040C - 0x040F
4
Flash SUPV Access Bytes
CFM Supervisor Access Register
0xFFFF_FFFF
0x0410 - 0x0413
4
Flash DATA Access Bytes
0xFFFF_FFFF
0x0414 - 0x0417
4
Flash Security Word
(see
”)
0xFFFF_FFFF
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
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part
numbers
indicated
here
currently
are
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available
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Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:MCF52234CVM60,
MCF52235CVM60
