Information

29.3.1.11 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 microcontroller or slower. Attempts to read greater than 12
bytes of data returns unknown data. This command is not accepted if the WEF, WIP, or
FS fields in the EzPort status register are 1.
29.3.1.12 Write FlexRAM
The Write FlexRAM (WRFLEXRAM) command allows the user to write four 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 the 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 for the FlexRAM results in the
value of the WEF flag being 1. See Flash memory map for EzPort access for more
information.
After receiving four bytes of data, EzPort writes the data to the FlexRAM. If greater or
less than four bytes of data is received, this command has unexpected results and may
result in the value of the WEF flag being 1.
This command is not accepted if the WEF, WIP or FS fields are 1 or if the WEN field is
0 in the EzPort status register.
29.3.1.13 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.
Command definition
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
568 Freescale Semiconductor, Inc.