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Chapter 23 1024 KByte Flash Module (S12XFTM1024K5V2)
MC9S12XE-Family Reference Manual Rev. 1.07
Freescale Semiconductor
907
23.4.2.22 Partition D-Flash Command
The Partition D-Flash command allows the user to allocate sectors within the D-Flash block for
applications and a partition within the buffer RAM for EEPROM access. The D-Flash block consists of
128 sectors with 256 bytes per sector. The Erase All Blocks command must be run prior to launching the
Partition D-Flash command.
Upon clearing CCIF to launch the Partition D-Flash command, the following actions are taken to define a
partition within the D-Flash block for direct access (DFPART) and a partition within the buffer RAM for
EEE use (ERPART):
Validate the DFPART and ERPART values provided:
— DFPART <= 128 (maximum number of 256 byte sectors in D-Flash block)
— ERPART <= 16 (maximum number of 256 byte sectors in buffer RAM)
— If ERPART > 0, 128 - DFPART >= 12 (minimum number of 256 byte sectors in the D-Flash
block required to support EEE)
— If ERPART > 0, ((128-DFPART)/ERPART) >= 8 (minimum ratio of D-Flash EEE space to
buffer RAM EEE space to support EEE)
Erase verify the D-Flash block and the EEE nonvolatile information register
Program DFPART to the EEE nonvolatile information register at global address 0x12_0000 (see
Table 23-6
)
Program a duplicate DFPART to the EEE nonvolatile information register at global address
0x12_0002 (see
Table 23-6
)
Program ERPART to the EEE nonvolatile information register at global address 0x12_0004 (see
Table 23-6
)
Program a duplicate ERPART to the EEE nonvolatile information register at global address
0x12_0006 (see
Table 23-6
)
The D-Flash user partition will start at global address 0x10_0000. The buffer RAM EEE partition will end
at global address 0x13_FFFF. After the Partition D-Flash operation has completed, the CCIF flag will set.
Running the Partition D-Flash command a second time will result in the ACCERR bit within the FSTAT
registerbeingset.Thedatavaluewrittencorrespondstothenumberof256bytesectorsallocatedforeither
direct D-Flash access (DFPART) or buffer RAM EEE access (ERPART).
Table 23-76. Partition D-Flash Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x20
Not required
001
Number of 256 byte sectors for the D-Flash user partition (DFPART)
010
Number of 256 byte sectors for buffer RAM EEE partition (ERPART)