NXP Semiconductors MKW01Z128, Reference Manual, Page: 535 / 884

The MCU must not read from the flash memory while commands are running (as
evidenced by CCIF=0) on that block. Read data cannot be guaranteed from a flash block
while any command is processing within that block. The block arbitration logic detects
any simultaneous access and reports this as a read collision error (see the
FSTAT[RDCOLERR] bit).
23.4.6 Read While Write (RWW)
The following simultaneous accesses are not allowed:
• Reading from program flash memory space while a flash command is active
(CCIF=0).
23.4.7 Flash Program and Erase
All flash functions except read require the user to setup and launch a flash command
through a series of peripheral bus writes.
The user cannot initiate any further flash commands until notified that the current
command has completed. The flash command structure and operation are detailed in
Flash Command Operations .
23.4.8 Flash Command Operations
Flash command operations are typically used to modify flash memory contents.
The next sections describe:
• The command write sequence used to set flash command parameters and launch
execution
• A description of all flash commands available
23.4.8.1 Command Write Sequence
Flash commands are specified using a command write sequence illustrated in Figure
23-3 . The flash memory module performs various checks on the command (FCCOB)
content and continues with command execution if all requirements are fulfilled.
Functional Description
MKW01Z128 MCU Reference Manual, Rev. 3, 04/2016
404 Freescale Semiconductor, Inc.