M29W640FT, M29W640FB
Figure 17. Programmer Equipment Chip Unprotect flowchart
Block protection
START
PROTECT ALL GROUPS
n = 0
CURRENT GROUP = 0
(1)
A6, A12, A15 = V
IH
E, G, A9 = V
ID
Wait 4µs
W = V
IL
Wait 10ms
W = V
IH
E, G = V
IH
ADDRESS = CURRENT GROUP ADDRESS
A0, A2, A3 = V , A1 =V
,
IL
IH
A9 = VID, Others = X
A6 =V
IH,
E = V
IL
Wait 4µs
G = V
IL
INCREMENT
CURRENT GROUP
Wait 60ns
Read DATA
NO
YES
DATA
=
00h
LAST
GROUP
NO
NO
++n
= 1000
YES
YES
A9 = V
A9 = V
E, G = V
IH
IH
E, G = V
IH
IH
FAIL
PASS
AI11556b
1. Block Protection Groups are shown in Appendix A, Tables 21 and 22.
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