Block protection
M29FxxxFT, M29FxxxFB
Figure 27. Programmer Equipment Block Protect Flowchart
START
ADDRESS= BLOCKADDRESS
W = V
IH
n = 0
G, A9 = V
E = V
IL
,
ID
Wait 4µs
W = V
IL
Wait 100µs
W = V
IH
E, G = V
A0, A6 = V
A1 = V
IH
,
IH
,
IL
E = V
IL
Wait 4µs
G = V
IL
Wait 60ns
Read DATA
DATA
=
01h
NO
YES
++n
= 25
NO
A9 = V
IH
E, G = V
IH
YES
PASS
A9 = V
E, G = V
IH
IH
AI03469b
FAIL
Address Inputs A19-A12 give the address of the block that is to be protected. It is imperative that they remain
stable during the operation.
During the Protect and Verify phases of the algorithm, Chip Enable E must be kept Low, VIL.
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NUMONYX [ NUMONYX B.V ]
