Chapter 19 Flash Module (S12ZFTMRZ)MC9S12ZVMB Family Reference Manual Rev. 1.3652 NXP Semiconductors19.4.7.4 Read Once CommandThe Read Once command provides read access to a reserved 64 byte field (8 phrases) located in thenonvolatile information register of P-Flash. The Read Once field is programmed using the Program Oncecommand described in Section 19.4.7.6. The Read Once command must not be executed from the Flashblock 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 theFCCOB indexed register. The CCIF flag will set after the Read Once operation has completed. Validphrase index values for the Read Once command range from 0x0000 to 0x0007. During execution of theRead Once command, any attempt to read addresses within P-Flash block will return invalid data.819.4.7.5 Program P-Flash CommandThe Program P-Flash operation will program a previously erased phrase in the P-Flash memory using anembedded algorithm.CAUTIONA P-Flash phrase must be in the erased state before being programmed.Cumulative programming of bits within a Flash phrase is not allowed.Table 19-39. Read Once Command FCCOB RequirementsRegister FCCOB ParametersFCCOB0 0x04 Not RequiredFCCOB1 Read Once phrase index (0x0000 - 0x0007)FCCOB2 Read Once word 0 valueFCCOB3 Read Once word 1 valueFCCOB4 Read Once word 2 valueFCCOB5 Read Once word 3 valueTable 19-40. Read Once Command Error HandlingRegister Error Bit Error ConditionFSTATACCERRSet if CCOBIX[2:0] != 001 at command launchSet if command not available in current mode (see Table 19-29)Set if an invalid phrase index is suppliedFPVIOL NoneMGSTAT1 Set if any errors have been encountered during the readMGSTAT0 Set if any non-correctable errors have been encountered during the readTable 19-41. Program P-Flash Command FCCOB RequirementsRegister FCCOB ParametersFCCOB0 0x06 Global address [23:16] toidentify P-Flash block
