MX29F200C T/B
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 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 require 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-verified 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 (B0H) during the time-
out period resets the derice 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 to period 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-suspend
program operation is complete, the system can once
again read array data within non-suspended sectors.
P/N:PM1250
REV. 1.0 , DEC. 14, 2005
9
MCNIX [ MACRONIX INTERNATIONAL ]
