MX29F002/002N
SET-UP AUTOMATIC SECTOR ERASE
COMMANDS
The Automatic Sector Erase does not require the device
to be entirely pre-programmed prior to executing the
Automatic Set-up Sector Erase command and Automatic
Sector Erase command. Upon executing the Automatic
Sector Erase command, the device will automatically
program and verify the sector(s) memory for an all-zero
data pattern. The system does not require to provide any
control or timing during these operations.
When the sector(s) is automatically verified to contain an
all-zero pattern, a self-timed sector erase and verification
begin. The erase and verification operations are com-
plete when the data on Q7 is "1" and the data on Q6 stops
toggling for two consecutive read cycles, at which time the
device returns to the Read mode. The system does not
required to provide any control or timing during these
operations.
When using the Automatic Sector Erase algorithm, note
that the erase automatically terminates when adequate
erase margin has been achieved for the memory array (no
erase verify command is required). Sector erase is a six-
bus cycle operation. There are two "unlock" write cycles.
These are followed by writing the set-up command-80H.
Two more "unlock" write cycles are then followed by the
sector erase command-30H. The sector address is
latched on the falling edge of WE, while the command(data)
is latched on the rising edge of WE. Sector addresses
selected are loaded into internal register on the sixth
falling edge of WE. Each successive sector load cycle
started by the falling edge of WE must begin within 30us
from the rising edge of the preceding WE. Otherwise, the
loading period ends and internal auto sector erase cycle
starts. (Monitor Q3 to determine if the sector erase timer
window is still open, see section Q3, Sector Erase Timer.)
Any command other than Sector Erase (30H) or Erase
Suspend (BOH) during the time-out period resets the
device to read mode.
ERASE SUSPEND
This command is only valid while the state machine is
executing Automatic Sector Erase operation, and therefore
will only be responded during Automatic Sector Erase
operation. Writing the Erase Suspend command during
the Sector Erase time-out immediately terminates the
time-out period and suspends the erase operation. After
this command has been executed, the command register
will initiate erase suspend mode. The state machine will
return to read mode automatically after suspend is ready.
At this time, state machine only allows the command
register to respond to the Read Memory Array, Erase
Resume and Program commands. The system can
determine the status of the program operation using the
Q7 or Q6 status bits, just as in the standard program
operation. After an erase-suspendend program operation
is complete, the system can once again read array data
within non-suspended sectors.
P/N: PM0547
REV. 1.1, JUN. 14, 2001
8
MCNIX [ MACRONIX INTERNATIONAL ]
