D A T A S H E E T
COMMAND DEFINITIONS
Writing specific address and data commands or se-
quences into the command register initiates device
operations. Table 9 defines the valid register command
sequences. Writing incorrect address and data val-
ues or writing them in the improper sequence resets
the device to reading array data.
The reset command may be written between the se-
quence cycles in an autoselect command sequence.
Once in the autoselect mode, the reset command
must be written to return to reading array data (also
applies to autoselect during Erase Suspend).
If DQ5 goes high during a program or erase operation,
writing the reset command returns the device to read-
ing array data (also applies during Erase Suspend).
All addresses are latched on the falling edge of WE#
or CE#, whichever happens later. All data is latched on
the rising edge of WE# or CE#, whichever happens
first. Refer to the appropriate timing diagrams in the
“AC Characteristics” section.
Autoselect Command Sequence
The autoselect command sequence allows the host
system to access the manufacturer and devices
codes, and determine whether or not a sector is pro-
tected. Table 9 shows the address and data
requirements. This method is an alternative to that
shown in Table 4, which is intended for PROM pro-
Reading Array Data
The device is automatically set to reading array data
after device power-up. No commands are required to
retrieve data. The device is also ready to read array
data after completing an Embedded Program or Em-
bedded Erase algorithm.
grammers and requires V on address bit A9.
ID
The autoselect command sequence is initiated by writ-
ing two unlock cycles, followed by the autoselect
command. The device then enters the autoselect
mode, and the system may read at any address any
number of times, without initiating another command
sequence.
After the device accepts an Erase Suspend com-
mand, the device enters the Erase Suspend mode.
The system can read array data using the standard
read timings, except that if it reads at an address
within erase-suspended sectors, the device outputs
status data. After completing a programming opera-
tion in the Erase Suspend mode, the system may
once again read array data with the same exception.
See “Erase Suspend/Erase Resume Commands” for
more information on this mode.
A read cycle at address XX00h retrieves the manufac-
turer code. A read cycle at address XX01h returns the
device code. A read cycle containing a sector address
(SA) and the address 02h in word mode (or 04h in
byte mode) returns 01h if that sector is protected, or
00h if it is unprotected. Refer to Tables 2 and 3 for
valid sector addresses.
The system must issue the reset command to re-en-
able the device for reading array data if DQ5 goes
high, or while in the autoselect mode. See the “Reset
Command” section, next.
The system must write the reset command to exit the
autoselect mode and return to reading array data.
See also “Requirements for Reading Array Data” in
the “Device Bus Operations” section for more informa-
tion. The Read Operations table provides the read
parameters, and Figure 13 shows the timing diagram.
Word/Byte Program Command Sequence
The system may program the device by word or byte,
depending on the state of the BYTE# pin. Program-
ming is a four-bus-cycle operation. The program
command sequence is initiated by writing two unlock
write cycles, followed by the program set-up com-
mand. The program address and data are written
next, which in turn initiate the Embedded Program al-
gorithm. The system is not required to provide further
controls or timings. The device automatically gener-
ates the program pulses and verifies the programmed
cell margin. Table 9 shows the address and data re-
quirements for the byte program command
sequence.
Reset Command
Writing the reset command to the device resets the
device to reading array data. Address bits are don’t
care for this command.
The reset command may be written between the se-
quence cycles in an erase command sequence before
erasing begins. This resets the device to reading array
data. Once erasure begins, however, the device ig-
nores reset commands until the operation is complete.
The reset command may be written between the se-
quence cycles in a program command sequence
before programming begins. This resets the device to
reading array data (also applies to programming in
Erase Suspend mode). Once programming begins,
however, the device ignores reset commands until the
operation is complete.
When the Embedded Program algorithm is complete,
the device then returns to reading array data and ad-
dresses are no longer latched. The system can
determine the status of the program operation by
using DQ7, DQ6, or RY/BY#. See “Write Operation
Status” for information on these status bits.
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Am29LV160D
May 5, 2006 22358B7
AMD [ AMD ]
