This Data Sheet may be revised by subsequent versions ©2003 Eon Silicon Solution, Inc., www.essi.com.tw
or modifications due to changes in technical specifications.
13
EN29F040A
Rev. B, Issue Date: 2004/04/01
completed the program or erase operation. If it is still toggling, the device did not complete the operation
successfully, and the system must write the reset command to return to reading array data.
The remaining scenario is that the system initially determines that the toggle bit is toggling and DQ5 has
not gone high. The system may continue to monitor the toggle bit and DQ5 through successive read
cycles, determining the status as described in the previous paragraph. Alternatively, it may choose to
perform other system tasks. In this case, the system must start at the beginning of the algorithm when it
returns to determine the status of the operation (top of Flowchart 6).
Table 6. Status Register Bits
DQ Name
Logic
Level
Definition
‘1’
Erase Complete or
erase Sector in Erase suspend
‘0’ Erase
On-Going
DQ7
Program Complete or
data of non-erase Sector during Erase Suspend
7
DATA
POLLING
DQ7
Program On-Going
‘-1-0-1-0-1-0-1-’
Erase or Program On-going
DQ6
Read during Erase Suspend
6
TOGGLE
BIT
‘-1-1-1-1-1-1-1-‘
Erase Complete
‘1’
Program or Erase Error
5 ERROR
BIT
‘0’
Program or Erase On-going
‘-1-0-1-0-1-0-1-’
Chip Erase, Sector Erase or Erase suspend on
currently addressed Sector.
(When DQ5=1, Erase Error due to currently
addressed Sector. Program during Erase
Suspend on-going at current address
2
TOGGLE
BIT
DQ2
Erase Suspend read on
non Erase Suspend Sector
Notes:
DQ7
DATA
Polling: indicates the P/E status check during Program or Erase, and on completion before checking bits DQ5
for Program or Erase Success.
DQ6 Toggle Bit: remains at constant level when P/E operations are complete or erase suspend is acknowledged.
Successive reads output complementary data on DQ6 while programming or Erase operation are on-going.
DQ5 Error Bit: set to “1” if failure in programming or erase
DQ2 Toggle Bit: indicates the Erase status and allows identification of the erased Sector.
