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15.5
Programming/Erasing Flash Memory
A software method, using the CPU, is employed to program and erase flash memory in the on-
board programming modes. There are four flash memory operating modes: program mode, erase
mode, program-verify mode, and erase-verify mode. Transitions to these modes can be made by
setting the PSU, ESU, P, E, PV, and EV bits in FLMCR.
For a description of state transition by FLMCR bit setting, see figure 15-10.
The flash memory cannot be read while being programmed or erased. Therefore, the program that
controls flash memory programming/erasing (the programming control program) should be
located and executed in on-chip RAM or external memory.
For the programming/erasing notes, see section 15.9, Notes on Flash Memory
Programming/Erasing. For the wait time after each bit in FLMCR is set or cleared, see section
18.2.5, Flash Memory Characteristics.
Notes: 1. Operation is not guaranteed if setting/resetting of the SWE, ESU, PSU, EV, PV, E, and
P bits in FLMCR is executed by a program in flash memory.
2. When programming or erasing, set the FWE pin input level to the high level, and set
FWE to 1. (programming/erasing will not be executed if FWE = 0).
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