HD6433044 Hitachi Semiconductor, HD6433044 Datasheet - Page 603

• Manufacturer Part Number: HD6433044
• Description: (HD64 Series) Hitachi Single-Chip Microcomputer
• Manufacturer: Hitachi Semiconductor

18.7.5 Erase-Verify Mode
In program-verify mode, after data has been erased, it is read to check that it has been erased
correctly. After the erase time has elapsed, exit erase mode (clear the E bit to 0), select erase-
verify mode (set the EV bit to 1), and wait 4 µs. Before reading data in erase-verify mode, write
H'FF dummy data to the address to be read. This dummy write applies an erase-verify voltage to
the memory cells at the latched address. If the flash memory is read in this state, the data at the
latched address will be read. After the dummy write, wait 2 µs before reading. If the read data
has been successfully erased, perform the dummy write, wait 2 µs, and erase-verify for the next
address. If the read data has not been erased, select erase mode again and repeat the same erase
and erase-verify sequence through the last address, until all memory data has been erased to 1. Do
not repeat the erase and erase-verify sequence more than 602 times, however.
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