ESMT
F49L320UA/F49L320BA
status bits, just as in the standard program operation. See
“Write Operation Status” f or more information.
operation. Further writes of the Resume command are
ignored. Another Erase Suspend command can be written
after the device has resumed erasing.
The system may also write the auto-select command
sequence when the device is in the Erase Suspend mode.
The device allows reading auto-select codes even at
addresses within erasing sectors, since the codes are not
stored in the memory array. When the device exits the
auto-select mode, the device reverts to the Erase Suspend
mode, and is ready for another valid operation.
Auto-select Command
The auto-select command sequence allows the host
system to access the manufacturer and devices codes, and
determine whether or not a sector is protected. Table 6
shows the address and data requirements. This method is
an alternative to that shown in Table 4, which is intended
for PROM programmers and requires VID on address bit
A9.
After an erase-suspended program operation is complete,
the system can once again read array data within
non-suspended sectors. The system can determine the
status of the program operation using the DQ7 or DQ6
status bits, just as in the standard program operation. See
“Write Operation Status” f or more information.
The auto-select command sequence is initiated by writing
two unlock cycles, followed by the auto-select command.
The device then enters the auto-select mode, and the
system may read at any address any number of times,
without initiating another command sequence. The read
cycles at address 04H, 08H, 0CH, and 00H retrieves the
ESMT manufacturer ID. A read cycle at address 01H
retrieves the device ID. A read cycle containing a sector
address(SA) and the address 02H returns 01H if that
sector is protected, or 00H if it is unprotected. Refer to
Tables 1 and 2 for valid sector addresses.
The system may also write the auto-select command
sequence when the device is in the Erase Suspend mode.
The device allows reading auto-select codes even at
addresses within erasing sectors, since the codes are not
stored in the memory array. When the device exits the
auto-select mode, the device reverts to the Erase Suspend
mode, and is ready for another valid operation.
The system must write the Erase Resume command
(address bits are “don’t care” as shown in Table 5) to exit
the erase suspend mode and continue the sector erase
The system must write the reset command to exit the
auto-select mode and return to reading array data.
7.3 Write Operation Status
The device provides several bits to determine the
RY/
, DQ7, and DQ6 each offer a method for
BY
status of a write operation: RY/ , DQ7, DQ6, DQ5,
determining whether a program or erase operation is
complete or in progress.
BY
DQ3, DQ2, and. Table
7
and the following
subsections describe the functions of these bits.
Table 7. Write Operation Status
DQ7
(Note1)
DQ5
(Note2)
Status
DQ6
DQ3 DQ2
RY/
BY
No
N/A
Embedded Program Algorithm
Embedded Erase Algorithm
Toggle
0
0
0
0
DQ7
0
Toggle
Toggle
No
Toggle
1
Toggle
0
1
Reading Erase Suspended
Sector
In Progress
1
N/A Toggle
Reading Non-Erase
Suspended Sector
Erase Suspend Program
Erase Suspended Mode
Data
DQ7
Data
Data Data Data
1
0
0
Toggle
Toggle
0
1
N/A
N/A
N/A
No
Toggle
Toggle
N/A
Embedded Program Algorithm
DQ7
Exceeded
Time Limits
Embedded Erase Algorithm
Erase Suspend Program
0
DQ7
Toggle
Toggle
1
1
1
N/A
0
0
Notes:
1. DQ7 and DQ2 require a valid address when reading status information. Refer to the appropriate subsection for further details.
2. DQ5 switches to ‘1’ when an Embedded Program or Embedded Erase operation has exceeded the maximum timing limits.
See “DQ5: Exceeded Timing Limits” for more information.
Elite Semiconductor Memory Technology Inc.
Publication Date : Sep. 2008
Revision: 1.1 17/55