MX29F022 Macronix, MX29F022 Datasheet - Page 8

• Manufacturer Part Number: MX29F022
• Description: 2M-BIT[256K x 8]CMOS FLASH MEMORY
• Manufacturer: Macronix

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 verifi-
cation begin. The erase and verification operations are
complete 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 verification 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
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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 (B0H)
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/Sec-
tor Erase operation. Writing the Erase Suspend com-
mand during the Sector Erase time-out immediately ter-
minates the time-out period and suspends the erase op-
eration. After this command has been executed, the
command register will initiate erase suspend mode. The
state machine will return to read mode automatically af-
ter 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.
MX29F022/022N
REV. 1.1, JUN. 14, 2001