mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 586

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

Command Definition
25.3.1.11 Read FCCOB Registers at High Speed
The Read FCCOB Registers at High Speed (FAST_RDFCCOB) command allows the
user to read the contents of the flash common command object registers. After receiving
the command, EzPort waits for one dummy byte of data before returning FCCOB register
data starting at FCCOB 0 and ending with FCCOB B.
This command can be run with an EzPort clock (EZP_CK) frequency half the internal
system clock frequency of the micro-controller or slower. Attempts to read greater than
12 bytes of data returns junk data. This command is not be accepted if the WEF, WIP, or
FS bit in the EzPort status register is set.
25.3.1.12 Write FlexRAM
The Write FlexRAM (WRFLEXRAM) command allows the user to write 4-bytes of data
to the FlexRAM. If the FlexRAM is configured for EEPROM operation, the
WRFLEXRAM command can effectively be used to create data records in EEPROM-
flash memory.
By default, after entering EzPort mode, the FlexRAM is configured for traditional RAM
operation and functions as direct RAM. The user can alter the FlexRAM configuration by
using WRFCCOB to execute a 'Set FlexRAM' or 'Program Partition' command within the
Flash.
The address of the FlexRAM location to be written is sent after the command word and
must be a 32-bit aligned address (the two LSBs must be zero). Attempts to write an
address which does not fall within the valid address range (see
Flash Memory Map for
EzPort
Access) for the FlexRAM results in the WEF flag being set.
After receiving 4 bytes of data, EzPort writes the data to the FlexRAM. If greater or less
than 4 bytes of data is received, this command has unexpected results and may result in
the WEF flag being set.
This command is not accepted if the WEF, WIP or FS bit is set or if the WEN bit is not
set in the EzPort status register.
25.3.1.13 Read FlexRAM
The Read FlexRAM (RDFLEXRAM) command returns data from the FlexRAM. If the
FlexRAM is configured for EEPROM operation, the RDFLEXRAM command can
effectively be used to read data from EEPROM-flash memory.
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
586
Freescale Semiconductor, Inc.