M29W640DT Datasheet, PDF (45/49 Pages) STMicroelectronics – 64 Mbit 8Mb x8 or 4Mb x16, Boot Block 3V Supply Flash Memory

Figure 17. Programmer Equipment Chip Unprotect Flowchart
M29W640DT, M29W640DB
START
PROTECT ALL GROUPS
n=0
CURRENT GROUP = 0
A6, A12, A15 = VIH(1)
E, G, A9 = VID
Wait 4µs
W = VIL
Wait 10ms
W = VIH
E, G = VIH
ADDRESS = CURRENT GROUP ADDRESS
A0 = VIL, A1, A6 = VIH
E = VIL
Wait 4µs
G = VIL
Wait 60ns
Read DATA
INCREMENT
CURRENT GROUP
NO ++n
= 1000
YES
A9 = VIH
E, G = VIH
FAIL
NO DATA YES
=
00h
LAST NO
GROUP
YES
A9 = VIH
E, G = VIH
PASS
AI05575
Note: Block Protection Groups are shown in APPENDIX D., Table 19. and Table 20..
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