MT28F400B3 Micron Technology, MT28F400B3 Datasheet - Page 13

• Manufacturer Part Number: MT28F400B3
• Description: (MT28F004B3 / MT28F400B3) FLASH MEMORY
• Manufacturer: Micron Technology

ERASE Sequence
block to logic 1. The command sequence necessary to
execute an ERASE is similar to that of a WRITE. To pro-
vide added security against accidental block erasure,
two
tiateanERASE of a block. In the first cycle, addresses
are “Don’t Care,” and ERASE SETUP (20h) is given. In
the second cycle, V
address within the block to be erased must be issued,
and ERASE CONFIRM (D0h) must be given. If a com-
mand other than ERASE CONFIRM is given, the write
and erase status bits (SR4 and SR5) are set, and the
device is in the status register read mode.
starts the ERASE of the addressed block. Any READ
operation outputs the status register contents on
DQ0–DQ7. V
completed (SR7 = 1). When the ERASE is completed,
the device is in the status register read mode until
another command is issued. Erasing the boot block
also requires that either the RP# pin be set to V
the WP# pin be held HIGH at the same time V
to V
Table 7:
NOTE:
09005aef8114a789
F45.fm - Rev. E 6/04 EN
1. SR3–SR5 must be cleared using CLEAR STATUS REGISTER.
Executing an ERASE sequence sets all bits within a
After the ERASE CONFIRM (D0h) is issued, the ISM
SR5
PPH
0
0
0
0
1
1
1
1
.
con-secutivecommandcyclesarerequiredtoini-
STATUS BITS
PP
SR4
Status Register Error Code Description
must be held at V
0
0
1
1
0
0
1
1
PP
must be brought to V
SR3
0
1
0
1
0
1
0
1
ERROR DESCRIPTION
No errors
V
WRITE error
WRITE error, V
ERASE error
ERASE error, V
Command sequencing error or WRITE/ERASE error
Command sequencing error, V
PPH
PP
voltage error
until the ERASE is
PP
PP
PPH
PP
HH
voltage not valid at time of ERASE CONFIRM
voltage not valid at time of WRITE
is set
SMART 3 BOOT BLOCK FLASH MEMORY
, an
or
13
ERASE Suspension
ERASE is in progress is ERASE SUSPEND. This com-
mand enables other commands to be executed while
pausing the ERASE in progress. When the device has
reached the erase suspend mode, the erase suspend
status bit (SR6) and ISM status bit (SR7) are set. The
device may now be given a READ ARRAY, ERASE
RESUME or READ STATUS REGISTER command. After
READ ARRAY has been issued, any location not within
the block being erased may be read. If ERASE RESUME
is issued before SR6 has been set, the device immedi-
ately proceeds with the ERASE in progress.
Error Handling
(SR3), write (SR4) and erase (SR5) status bits may be
checked. If one or a combination of these three bits
has been set, an error has occurred. The ISM cannot
reset these three bits. To clear these bits, CLEAR STA-
TUS REGISTER (50h) must be given. If the V
bit (SR3) is set, further WRITE or ERASE operations
cannot resume until the status register is cleared. Table
4 lists the combination of errors.
PP
The only command that may be issued while an
After the ISM status bit (SR7) has been set, the V
voltage error, with WRITE and ERASE errors
Micron Technology, Inc., reserves the right to change products or specifications without notice.
1
©2003 Micron Technology, Inc. All rights reserved.
4Mb
PP
status
PP