Command interface
M29W064FT, M29W064FB
4.2.5
Quadruple Word Program command
This is used to write a page of four adjacent words (or 8 adjacent bytes), in x 16 mode,
simultaneously. The addresses of the four words must differ only in A1 and A0.
Five bus write cycles are necessary to issue the command:
●
●
●
●
●
The first bus cycle sets up the command
The second bus cycle latches the address and the data of the first word to be written
The third bus cycle latches the address and the data of the second word to be written
The fourth bus cycle latches the address and the data of the third word to be written
The fifth bus cycle latches the address and the data of the fourth word to be written and
starts the program/erase controller.
4.2.6
Unlock Bypass command
The Unlock Bypass command is used in conjunction with the Unlock Bypass Program
command to program the memory faster than with the standard program commands. When
the cycle time to the device is long, considerable time saving can be made by using these
commands. Three bus write operations are required to issue the Unlock Bypass command.
Once the Unlock Bypass command has been issued the memory will only accept the Unlock
Bypass Program command and the Unlock Bypass Reset command. The memory can be
read as if in read mode.
When V
PP
is applied to the V
PP
/write protect pin the memory automatically enters the
unlock bypass mode and the Unlock Bypass Program command can be issued immediately.
4.2.7
Unlock Bypass Program command
The Unlock Bypass command is used in conjunction with the Unlock Bypass Program
command to program the memory. When the cycle time to the device is long, considerable
time saving can be made by using these commands. Three bus write operations are
required to issue the Unlock Bypass command.
Once the Unlock Bypass command has been issued the memory will only accept the Unlock
Bypass Program command and the Unlock Bypass Reset command. The memory can be
read as if in read mode.
The memory offers accelerated program operations through the V
PP
/write protect pin. When
the system asserts V
PP
on the V
PP
/write protect pin, the memory automatically enters the
unlock bypass mode. The system may then write the two-cycle unlock bypass program
command sequence. The memory uses the higher voltage on the V
PP
/write protect pin, to
accelerate the unlock bypass program operation.
Never raise V
PP
/write protect to V
PP
from any mode except read mode, otherwise the
memory may be left in an indeterminate state.
4.2.8
Unlock Bypass Reset command
The Unlock Bypass Reset command can be used to return to read/reset mode from Unlock
bypass mode. Two bus write operations are required to issue the Unlock Bypass Reset
command. Read/Reset command does not exit from unlock bypass mode.
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NUMONYX [ NUMONYX B.V ]
