APPENDIX D LIST OF CAUTIONS
User’s Manual U18172EJ2V0UD
320
(13/15)
Chapter
Cl
assi
fi
cati
on
Function Details
of
Function
Cautions Page
Self programming processing must be included in the program before performing
self programming.
p. 222
No instructions can be executed while a self programming command is being
executed. Therefore, clear and restart the watchdog timer counter in advance so
that the watchdog timer does not overflow during self programming. Refer to
Table 16-11 for the time taken for the execution of self programming.
p. 225
Interrupts that occur during self programming can be acknowledged after self
programming mode ends. To avoid this operation, disable interrupt servicing (by
setting MK0 to FFH, and executing the DI instruction)
before a mode is shifted
from the normal mode to the self programming mode with a specific sequence.
p. 225
RAM is not used while a self programming command is being executed.
p. 225
If the supply voltage drops or the reset signal is input while the flash memory is
being written or erased, writing/erasing is not guaranteed.
p. 225
The value of the blank data set during block erasure is FFH.
p. 225
Set the CPU clock so that it is 1 MHz or more during self programming.
p. 225
Execute the NOP and HALT instructions immediately after executing a specific
sequence to set self-programming mode, then execute self programming. At this
time, the HALT instruction is automatically released after 10
µ
s (MAX.) + 2 CPU
clocks (f
CPU
).
p. 225
If the clock of the oscillator or an external clock is selected as the system clock,
execute the NOP and HALT instructions immediately after executing a specific
sequence to set self-programming mode, wait for 8
µ
s after releasing the HALT
status, and then execute self programming.
p. 225
Check FPRERR using a 1-bit memory manipulation instruction.
p. 225
The state of the pins in self programming mode is the same as that in HALT
mode.
p. 225
Since the security function set via on-board/off-board programming is disabled in
self programming mode, the self programming command can be executed
regardless of the security function setting. To disable write or erase processing
during self programming, set the protect byte.
p. 225
Be sure to clear bits 4 to 7 of flash address pointer H (FLAPH) and flash address
pointer H compare register (FLAPHC) to 0 before executing the self programming
command. If the value of these bits is 1 when executing the self programming
command, there is a possibility that device does not operate normally.
p. 225
Self
programming
function
Clear the value of the FLCMD register to 00H immediately before setting self-
programming mode and normal operation mode.
p. 225
Cautions in the case of setting the self programming mode, refer to 16.8.2
Cautions on self programming function.
p. 226
Set the CPU clock so that it is 1 MHz or more during self programming.
p. 226
Execute the NOP and HALT instructions immediately after executing a specific
sequence to set self-programming mode, then execute self programming. At this
time, the HALT instruction is automatically released after 10
µ
s (MAX.) + 2 CPU
clocks (f
CPU
).
p. 226
If the clock of the oscillator or an external clock is selected as the system clock,
execute the NOP and HALT instructions immediately after executing a specific
sequence to set self-programming mode, wait for 8
µ
s after releasing the HALT
status, and then execute self programming.
p. 226
Chapter 16
Soft
Flash
memory
FLPMC: Flash
programming
mode control
register
Clear the value of the FLCMD register to 00H immediately before setting self
programming mode and normal operation mode.
p. 226