
AS29LV800
3/22/01;
V.1.0
Alliance Semiconductor
P. 10 of 25
March 2001
Status operations
Write operation status
DQ2 toggles when an erase-suspended sector is read repeatedly.
DQ6 toggles when any address is read repeatedly.
DQ2 = 1 if byte address being programmed is read during erase-suspend program mode.
DQ2 toggles when the read address applied points to a sector which is undergoing erase, suspended erase, or a failure to erase.
DATA polling (DQ7)
Only active during automated on-chip algorithms or sector erase time outs. DQ7 reflects
complement of data last written when read during the automated on-chip program algorithm (0
during erase algorithm); reflects true data when read after completion of an automated on-chip
program algorithm (1 after completion of erase agorithm).
Toggle bit 1 (DQ6)
Active during automated on-chip algorithms or sector erase time outs. DQ6 toggles when CE or OE
toggles, or an Erase Resume command is invoked. DQ6 is valid after the rising edge of the fourth
pulse of WE during programming; after the rising edge of the sixth WE pulse during chip erase;
after the last rising edge of the sector erase WE pulse for sector erase. For protected sectors,
DQ6 toggles for <1 μs during program mode writes, and <5 μs during erase (if all selected sectors
are protected).
Exceeding time limit
(DQ5)
Indicates unsuccessful completion of program/erase operation (DQ5 = 1). DATA polling remains
active. If DQ5 = 1 during chip erase, all or some sectors are defective; during byte programming or
sector erase, the sector is defective (in this case, reset the device and execute a program or erase
command sequence to continue working with functional sectors). Attempting to program 0 to 1
will set DQ5 = 1.
Sector erase timer
(DQ3)
Checks whether sector erase timer window is open. If DQ3 = 1, erase is in progress; no commands
will be accepted. If DQ3 = 0, the device will accept sector erase commands. Check DQ3 before and
after each Sector Erase command to verify that the command was accepted.
Toggle bit 2 (DQ2)
During sector erase, DQ2 toggles with OE or CE only during an attempt to read a sector being
erased. During chip erase, DQ2 toggles with OE or CE for all addresses. If DQ5 = 1, DQ2 toggles
only at sector addresses where failure occurred, and will not toggle at other sector addresses. Use
DQ2 in conjunction with DQ6 to determine whether device is in auto erase or erase suspend
mode.
Status
DQ7
DQ6
DQ5
DQ3
DQ2
RY/BY
Standard mode
Auto programming
DQ7
Toggle
0
N/A
No toggle
Toggle
0
Program/erase in auto erase
0
Toggle
0
1
0
Erase suspend mode
Read erasing sector
1
No toggle
0
N/A
Toggle
1
Read non-erasing sector
Data
Data
Data
Data
Data
Toggle
1
Program in erase suspend
DQ7
Toggle
0
N/A
0
Exceeded time limits
Auto programming (byte)
DQ7
Toggle
1
N/A
No toggle
Toggle
1
Program/erase in auto erase
0
Toggle
1
N/A
1
Program in erase suspend
(non-erase suspended sector)
DQ7
Toggle
1
N/A
No toggle
1