M29W128GH, M29W128GL
Bus operations
programmer method (8-bit mode) and Table 7: Read electronic signature - auto select mode
- programmer method (16-bit mode).
These codes can also be accessed by issuing an Auto Select command (see Section 6.1.2:
Auto Select command).
3.7.2
Verify extended memory block protection indicator
The extended memory block is either factory locked or customer lockable.
The protection status of the extended memory block (factory locked or customer lockable)
can be accessed by reading the extended memory block protection indicator. It can be read
in Auto Select mode using either the programmer (see Table 8 and Table 9) or the in-system
method (see Table 10 and Table 11).
The protection status of the extended memory block is then output on bit DQ7 of the Data
input/outputs (see Table 4 and Table 5, Bus operations in 8-bit and 16-bit mode).
3.7.3
3.7.4
Verify block protection status
The protection status of a block can be directly accessed by performing a read operation
with control signals and addresses set as shown in Table 8 and Table 9.
If the block is protected, then 01h (in x 8 mode) is output on Data input/outputs DQ0-DQ7,
otherwise 00h is output.
Hardware Block Protect
The V /WP pin can be used to protect the highest or lowest block. When V /WP is at V
PP
PP
IL
the highest (M29W128GH) or lowest block (M29W128GL) is protected and remains
protected regardless of the block protection status or the Reset pin state.
19/94
NUMONYX [ NUMONYX B.V ]
