mc9s12vr48 Freescale Semiconductor, Inc, mc9s12vr48 Datasheet - Page 493

• Manufacturer Part Number: mc9s12vr48
• Description: S12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

17.4.6.4
The Read Once command provides read access to a reserved 64 byte field (8 phrases) located in the
nonvolatile information register of P-Flash. The Read Once field is programmed using the Program Once
command described in
block containing the Program Once reserved field to avoid code runaway.
Upon clearing CCIF to launch the Read Once command, a Read Once phrase is fetched and stored in the
FCCOB indexed register. The CCIF flag will set after the Read Once operation has completed. Valid
phrase index values for the Read Once command range from 0x0000 to 0x0007. During execution of the
Read Once command, any attempt to read addresses within P-Flash block will return invalid data.
Freescale Semiconductor
Register
FSTAT
Read Once Command
Table 17-35. Erase Verify P-Flash Section Command Error Handling
CCOBIX[2:0]
MGSTAT1
MGSTAT0
ACCERR
Error Bit
FPVIOL
Section
Table 17-36. Read Once Command FCCOB Requirements
000
001
010
011
100
101
17.4.6.6. The Read Once command must not be executed from the Flash
MC9S12VR Family Reference Manual, Rev. 2.2
Preliminary - Subject to Change Without Notice
Set if CCOBIX[2:0] != 010 at command launch
Set if command not available in current mode (see
Set if an invalid global address [17:0] is supplied see )
Set if a misaligned phrase address is supplied (global address [2:0] != 000)
Set if the requested section crosses a the P-Flash address boundary
None
Set if any errors have been encountered during the read or if blank check failed.
Set if any non-correctable errors have been encountered during the read or if
blank check failed.
Read Once phrase index (0x0000 - 0x0007)
0x04
Read Once word 0 value
Read Once word 1 value
Read Once word 2 value
Read Once word 3 value
FCCOB Parameters
Error Condition
Not Required
64 KByte Flash Module (S12FTMRG64K512V1)
Table
17-26)
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