
28F6408W30, 28F3204W30, 28F320W30, 28F640W30
Preliminary
59
Appendix A  Flash Write State Machine (WSM)
This table shows the command state transitions based on incoming commands. Only one partition 
can be actively programming or erasing at a time. Each partition stays in its last output state (Array, 
ID/CFI or Status) until a new command changes it. The next WSM state does not depend on the 
partition
’
s output state.
Figure 29. Write State Machine 
—
 Next State Table (Sheet 1 of 2)
Chip
 Next State after Command Input 
Read
Array
(3)
Program
Setup
(4,5)
Erase
Setup
(4,5)
Enhanced
Factory
Pgm 
Setup
(4)
BE Confirm,
P/E Resume,
ULB 
Confirm
(9)
Program/
Erase 
Suspend
Read
Status
Clear 
Status 
Register
(6)
Read
ID/Query
(FFH)
(10H/40H)
(20H)
(30H)
(D0H)
(B0H)
(70H)
(50H)
(90H, 98H)
Ready
Ready
Program
Setup
Erase
Setup
EFP
Setup
Ready
Lock/CR Setup
Ready (Lock Error)
Ready
Ready (Lock Error)
Setup
OTP Busy
Busy
Setup
Program Busy
Busy
Program Busy
Pgm Susp
Program Busy
Suspend
Program Suspend
Pgm Busy
Program Suspend
Setup
Ready (Error)
Erase Busy
Ready (Error)
Busy
Erase Busy
Erase Susp
Erase Busy
Suspend
Erase
Suspend
Pgm in 
Erase 
Susp Setup
Erase Suspend
Erase Busy
Erase Suspend
Setup
Program in Erase Suspend Busy
Busy
Program in Erase Suspend Busy
Pgm Susp in
Erase Susp
Program in Erase Suspend Busy
Suspend
Program Suspend in Erase Suspend
Pgm in Erase
Susp Busy
Program Suspend in Erase Suspend
Erase Suspend (Lock Error)
Erase Susp
Erase Suspend
(Lock Error)
Ready (Error)
Setup
Ready (Error)
EFP Busy
EFP Busy
(7)
Verify Busy
(7)
EFP Busy
EFP Verify
Output
 Next State after Command Input
Status
Status
Status
ID/Query
W
O
(
Lock/CR Setup,
Lock/CR Setup in Erase Susp
OTP Busy
Current Chip 
State
(8)
Ready,
Pgm Busy,
Pgm Suspend,
Erase Busy,
Erase Suspend,
Pgm In Erase Susp Busy,
Pgm Susp In Erase Susp         
Pgm Setup,
Erase Setup,
OTP Setup,
Pgm in Erase Susp Setup,
EFP Setup,
EFP Busy,
Verify Busy                               
Lock/CR Setup in Erase 
Suspend
Erase
Program
Program in 
Erase Suspend
OTP
Enhanced
Factory
Program
Output 
does not 
change
Array
(3)
Status
Output does not change
Status