Motorola ColdFire MCF5281 - Manual (Page 133)

ColdFire Flash Module (CFM)
Freescale Semiconductor 6-21
6.4.3.4 Flash User Mode Illegal Operations
The ACCERR flag will be set during a command write sequence if any of the illegal operations below are
performed. Such operations will cause the command sequence to immediately abort.
1. Writing to the CFM array before initializing CFMCLKD.
2. Writing to the CFM array while in emulation mode.
3. Writing a byte or a word to the CFM array. Only 32-bit longword programming is allowed.
4. Writing to the CFM array while CBEIF is not set.
5. Writing an invalid user command to the CFMCMD.
6. Writing to any CFM other than CFMCMD after writing a longword to the CFM array.
7. Writing a second command to CFMCMD before executing the previously written command.
8. Writing to any CFM register other than CFMUSTAT (to clear CBEIF) after writing to the
command register.
9. Entering stop mode while a program or erase command is in progress.
10. Aborting a command sequence by writing a 0 to CBEIF after the longword write to the CFM
array or after writing a command to CFMCMD and before launching it.
The PVIOL flag will be set during a command write sequence after the longword write to the CFM array
if any of the illegal operations below are performed. Such operations will cause the command sequence to
immediately abort.
1. Writing to an address in a protected area of the CFM array.
2. Writing a mass erase command to CFMCMD while any logical sector is protected (see
Section 6.3.4.4, “CFM Protection Register (CFMPROT) ”).
If a Flash physical block is read during a program or erase operation on that block (CFMUSTAT bit CCIF
= 0), the read will return non-valid data and the ACCERR flag will not be set.
6.4.4 Stop Mode
If a command is active (CCIF = 0) when the MCU enters stop mode, the command sequence monitor
performs the following:
1. The command in progress aborts
2. The Flash high voltage circuitry switches off and any pending command (CBEIF = 0) does not
executed when the MCU exits stop mode.
3. The CCIF and ACCERR flags are set if a command is active when the MCU enters stop mode.
NOTE
The state of any longword(s) being programmed or any erase pages/physical
blocks being erased is not guaranteed if the MCU enters stop mode with a
command in progress.
WARNING
Active commands are immediately aborted when the MCU enters stop
mode. Do not execute the STOP instruction during program and erase
operations.
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3