w83877atd Winbond Electronics Corp America, w83877atd Datasheet - Page 113

• Manufacturer Part Number: w83877atd
• Description: Winbond I/o
• Manufacturer: Winbond Electronics Corp America

8.2.8 Configuration Register 7 (CR7), default = 00H
When the device is in Extended Function mode and EFIR is 07H, the CR7 register can be accessed
through EFDR. The bit definitions are as follows:
FDD D type 1, 0 (Bit 7, 6):
These two bits select the type of FDD D.
Three mode FDD select (EN3MODE = 1):
FDD C type 1, 0 (Bit 5, 4):
These two bits select the type of FDD C.
Three mode FDD select (EN3MODE = 1):
FDD B type 1, 0 (Bit 3, 2):
These two bits select the type of FDD B.
Three mode FDD select (EN3MODE = 1):
00
01
10
11
00
01
10
11
00
01
10
11
Selects normal mode. When RWC = 0, the data transfer rate is 250 Kb/s. When
RWC = 1, the data transfer rate is 500 Kb/s.
RWC = 0, selects 1.2 MB high-density FDD.
RWC = 1, selects 1.44 MB high-density FDD.
Don't care RWC, selects 720 KB double-density FDD.
Selects normal mode. When RWC = 0, the data transfer rate is 250 kb/s. When
RWC = 1, he data transfer rate is 500 kb/s.
RWC = 0, selects 1.2 MB high-density FDD.
RWC = 1, selects 1.44 MB high-density FDD.
Don't care RWC, selects 720 KB double-density FDD.
Selects normal mode. When RWC = 0, the data transfer rate is 250 Kb/s. When
RWC = 1, the data transfer rate is 500 Kb/s.
RWC = 0, selects 1.2 MB high-density FDD.
RWC = 1, selects 1.44 MB high-density FDD.
Don't care RWC, selects 720 KB double-density FDD.
7
6
5
4
3
- 109 -
2
1
0
FDD A type 0
FDD A type 1
FDD B type 0
FDD B type 1
FDD C type 0
FDD C type 1
FDD D type 0
FDD D type 1
Publication Release Date: April 1998
W83877ATF
Version 0.51