CHIP UNPROTECT
The MX29LV008T/B also features the chip unprotect
mode, so that all sectors are unprotected after chip
unprotect is completed to incorporate any changes in the
code. It is recommended to protect all sectors before
activating chip unprotect mode.
To activate this mode, the programming equipment must
force VID on control pin OE and address pin A9. The CE
pins must be set at VIL. Pins A6 must be set to VIH.
Refer to chip unprotect algorithm and waveform for the
chip unprotect algorithm. The unprotection mechanism
begins on the falling edge of the WE pulse and is
terminated on the rising edge.
It is also possible to determine if the chip is unprotected
in the system by writing the Read Silicon ID command.
Performing a read operation with A1=VIH, it will produce
00H at data outputs(Q0-Q7) for an unprotected sector.
It is noted that all sectors are unprotected after the chip
unprotect algorithm is completed.
MX29LV008T/B
P/N:PM0718
REV. 1.0, JUL. 31, 2001
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