w49v002fa Winbond Electronics Corp America, w49v002fa Datasheet - Page 22

• Manufacturer Part Number: w49v002fa
• Description: 256k X 8 Cmos Flash Memory With Fwh Interface
• Manufacturer: Winbond Electronics Corp America

TIMING WAVEFORMS FOR FWH INTERFACE MODE
Read Cycle Timing Diagram
Write Cycle Timing Diagram
FWH[3:0]
#RESET
FWH4
FWH[3:0]
#RESET
FWH4
CLK
Note: When A22 = high, the host will read the BIOS code from the FWH device.
CLK
While A22 = low, the host will read the GPI (Add = FFBC0100) or
Product ID (Add = FFBC0000/FFBC0001) from the FWH device
1 Clock
1 Clock
T
SU
1101b
Start
FWH
Read
1110b
Start
FWH
Write
T
HD
1 Clock
1 Clock
0000b
IDSEL
0000b
IDSEL
XXXXb
XXXXb
XA[22]XXb XXA[17:16]
XXXXb
Load Address in 7 Clocks
Load Address in 7 Clocks
XXA[17:16]b
T
T CYC
CYC
A[15:12]
A[15:12]
Address
Address
A[11:8]
A[11:8]
- 22 -
T
A[7:4]
SU
A[7:4]
T
HD
A[3:0]
A[3:0]
0000b
0000b]
M Size
M Size
Load Data in 2 Clocks
D[3:0]
1111b
2 Clocks
Data
TAR
T SU
Tri-State 0000b
D[7:4]
T HD
1 Clock
1111b
Sync
2 Clocks
T
TAR
KQ
Tri-State
Data out 2 Clocks
D[3:0]
W49V002FA
Data
1 Clock
0000b
D[7:4]
Sync
TAR
TAR
1 Clock
Next Start
1 Clock
Next Start
0000b
0000b