SH7018 datasheet(353/431 Pages) RENESAS

353 / 431 page

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16.7.2

Program-Verify Mode

In program-verify mode, the data written in program mode is read to check whether it has been

correctly written in the flash memory.

After the elapse of a given programming time, the programming mode is exited (the P bit in

FLMCR1 is cleared, then the PSUn bit is cleared at least 5 µs later). The watchdog timer is cleared

after the elapse of 5 µs or more, and the operating mode is switched to program-verify mode by

setting the PV bit in FLMCR1. Before reading in program-verify mode, a dummy write of H'FF

data should be made to the addresses to be read. The dummy write should be executed after the

elapse of 4 µs or more. When the flash memory is read in this state (verify data is read in 32-bit

units), the data at the latched address is read. Wait at least 2 µs after the dummy write before

performing this read operation. Next, the written data is compared with the verify data, and

reprogram data is computed (see figure 16.12) and transferred to the reprogram data area. After

128 bytes of data have been verified, exit program verify mode, wait for at least 2 µs, clear the

SWE bit in FLMCR1, then wait for at least 100 µs. If reprogramming is necessary, set program

mode again, and repeat the program/program-verify sequence as before. However, ensure that the

program/program-verify sequence is not repeated more than 1,000 times on the same bits.

SH7018 Datasheet(PDF) 353 Page - Renesas Technology Corp