HD64F3644PV Datasheet, PDF (176/551 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 6 ROM
High-Speed, High-Reliability Erasing: The flash memory in the H8/3644F, H8/3643F, and
H8/3642AF uses a high-speed, high-reliability erasing procedure. This procedure provides higher
erasing speed without subjecting the device to voltage stress and without sacrificing the reliability
of data reliability.
Figure 6.19 shows the basic high-speed, high-reliability erasing flowchart. Tables 6.15 and 6.16
list the electrical characteristics during erasing.
Start
Program all bits to 0*
Address = 0
n=0
n+1→n
Erase setup/erase command
Wait (10 ms)
Erase-verify command
Address + 1 → address
No
Wait (6 µs)
Verify?
OK
Last address?
Yes
End
NG
No
n = 3000?
Yes
Error
Note: * Follow the high-speed, high-reliability programming flowchart in programming all bits.
If 0 has already been written, perform programming for unprogrammed bits.
Figure 6.19 High-Speed, High-Reliability Erasing
Rev. 6.00 Sep 12, 2006 page 154 of 526
REJ09B0326-0600