HY29LV320 Datasheet, PDF (16/44 Pages) Hynix Semiconductor – 32 Mbit (2M x 16) Low Voltage Flash Memory

HY29LV320
retrieve data in this mode. See Read Operation
section for additional information.
After the device accepts an Erase Suspend com-
mand, the HY29LV320 enters the erase-suspend-
read mode, after which the system can read data
from any non-erase-suspended sector. After com-
pleting a programming operation in the Erase
Suspend mode, the system may once again read
array data with the same exception. See the Erase
Suspend/Erase Resume Commands section for
more information.
Reset Command
Writing the Reset command resets the sectors to
the Read or Erase-Suspend mode. Address bits
are don’t cares for this command.
As described above, a Reset command is not nor-
mally required to begin reading array data. How-
ever, a Reset command must be issued in order
to read array data in the following cases:
n If the device is in the Electronic ID mode, a
Reset command must be written to return to
the Read array mode. If the device was in the
Erase Suspend mode when the device entered
the Electronic ID mode, writing the Reset com-
mand returns the device to the Erase Suspend
mode.
Note: When in the Electronic ID bus operation mode,
the device returns to the Read array mode when V_ID is
removed from the A[9] pin. The Reset command is not
required in this case.
n If the device is in the CFI Query mode, a Reset
command must be written to return to the ar-
ray Read mode.
n If DQ[5] (Exceeded Time Limit) goes High dur-
ing a program or erase operation, a Reset com-
mand must be invoked to return the sectors to
the Read mode (or to the Erase Suspend mode
if the device was in Erase Suspend when the
Program command was issued).
The Reset command may also be used to abort
certain command sequences:
n In a Sector Erase or Chip Erase command se-
quence, the Reset command may be written
at any time before erasing actually begins, in-
cluding, for the Sector Erase command, be-
tween the cycles that specify the sectors to be
erased (see Sector Erase command descrip-
16
tion). This aborts the command and resets the
device to the Read mode. Once erasure be-
gins, however, the device ignores the Reset
command until the operation is complete.
n In a Program command sequence, the Reset
command may be written between the se-
quence cycles before programming actually be-
gins. This aborts the command and resets the
device to the Read mode, or to the Erase Sus-
pend mode if the Program command sequence
is written while the device is in the Erase Sus-
pend mode. Once programming begins, how-
ever, the device ignores the Reset command
until the operation is complete.
n The Reset command may be written between
the cycles in an Electronic ID command se-
quence to abort that command. As described
above, once in the Electronic ID mode, the
Reset command must be written to return to
the array Read mode.
Note: The Reset command does not return the device
from Sec² Region access to normal array access. See
descriptions of Enter/Exit Sec² Region commands for
additional information.
Enter/Exit Sec² Region Command Sequences
The system can access the Sec² region of the
device by issuing the Enter Sec² Region Command
sequence. The device continues to access the
Sec² region until the system issues the Exit Sec²
Region Command sequence, which returns the
device to normal operation.
Note that a hardware reset will reset the device to
the Read Array mode.
Program Command Sequence
The system programs the device a word at a time
by issuing the appropriate four-cycle Program
Command sequence as shown in Table 9. The
sequence begins by writing two unlock cycles, fol-
lowed by the program setup command and, lastly,
the program address and data. This initiates the
Automatic Program algorithm that automatically
provides internally generated program pulses and
verifies the programmed cell margin. The host is
not required to provide further controls or timings
during this operation. When the Automatic Pro-
gram algorithm is complete, the device returns to
the reading array data mode. Several methods
are provided to allow the host to determine the
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