Signal descriptions
M29W064FT, M29W064FB
2.9
Reset/block temporary unprotect (RP)
The reset/block temporary unprotect pin can be used to apply a hardware reset to the
memory or to temporarily unprotect all blocks that have been protected.
Note that if V
PP
/WP is at V
IL
, then the two outermost boot blocks will remain protected even
if RP is at V
ID
.
A hardware reset is achieved by holding reset/block temporary unprotect Low, V
IL
, for at
least t
PLPX
. After reset/block temporary unprotect goes High, V
IH
, the memory will be ready
for bus read and bus write operations after t
PHEL
or t
RHEL
, whichever occurs last. See
and
for more
details.
Holding RP at V
ID
will temporarily unprotect the protected blocks in the memory. Program
and erase operations on all blocks will be possible. The transition from V
IH
to V
ID
must be
slower than t
PHPHH
.
2.10
Ready/busy output (RB)
The ready/busy pin is an open-drain output that can be used to identify when the device is
performing a program or erase operation. During program or erase operations ready/busy is
Low, V
OL
. Ready/busy is high-impedance during read mode, Auto select mode and erase
suspend mode.
After a hardware reset, bus read and bus write operations cannot begin until ready/busy
becomes high-impedance. See
and
for more
details.
The use of an open-drain output allows the ready/busy pins from several memories to be
connected to a single pull-up resistor. A Low will then indicate that one, or more, of the
memories is busy.
2.11
Byte/word organization select (BYTE)
The byte/word organization select pin is used to switch between the x 8 and x 16 bus modes
of the memory. When byte/word organization select is Low, V
IL
, the memory is in x 8 mode,
when it is High, V
IH
, the memory is in x 16 mode.
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NUMONYX [ NUMONYX B.V ]
