W83877 Winbond Electronics Corp America, W83877 Datasheet - Page 78

• Manufacturer Part Number: W83877
• Description: Winbond I/O
• Manufacturer: Winbond Electronics Corp America

IDEPWD (Bit 2):
This bit controls the power of the IDE.
FDCTRI (Bit 1):
This bit enables or disables the tri-state outputs of the FDC in power-down mode.
IDETRI (BIt 0):
This bit enables or disables the tri-state outputs of the IDE in power-down mode.
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 A type 1, 0 (Bit 1, 0):
These two bits select the type of FDD A.
Three mode FDD select (EN3MODE = 1):
FDD B type 1, 0 (Bit 3, 2):
RWC
1
0
1
0
1
0
1
00
01
10
11
Puts the FDC in power-down mode.
Power is supplied to the IDE. (default)
Puts the IDE in power-down mode.
The output pins of the FDC will not be tri-stated when FDC is in power-down mode.
The output pins of the FDC will be tri-stated when FDC is in power-down mode.
The output pins of the IDE will not be tri-stated when IDE is in power-down mode.
The output pins of the IDE will be tri-stated when IDE is in power-down mode.
Selects normal mode. When RWC = 0, the data transfer rate is 250 Kb/s. When
Don't care RWC
RWC = 1, selects 1.44 MB high-density FDD.
RWC = 0, selects 1.2 MB high-density FDD.
= 1, the data transfer rate is 500 Kb/s.
7
6
,
selects 720 KB double-density FDD.
5
4
3
- 78 -
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
W83877F