W83877ATG Nuvoton Technology Corporation of America, W83877ATG Datasheet - Page 120

• Manufacturer Part Number: W83877ATG
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83877ATG

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Bit 7: Reserved.
TXW4C (Bit 6):
This bit is active high. When active, the IR controller will wait for a 4-character period of time from the
end of last receiving before it can start transmitting data.
RXW4C (Bit 5):
This bit is active high. When active, the IR controller will wait for a 4-character period of time from the
end of last transmitting before it can start receiving data.
ENIFCHG (Bit 4):
This bit is active high. When active, it enables host interface mode change, which is determined by
IDENT (Bit 3) and MFM (Bit 2).
IDENT (Bit 3):
This bit indicates the type of drive being accessed and changes the level on RWC (pin 87).
When hardware reset or ENIFCHG is a logic 1, IDENT and MFM select one of three interface modes,
as shown in Table 8-5.
Table 8-5
MFM (Bit 2):
This bit and IDENT select one of the three interface modes (PS/2 mode, Model 30, or PC/AT mode).
INTVERTZ (Bit 1):
This bit determines the polarity of all FDD interface signals.
When this bit is a logic 0, indicates a second drive is installed and is reflected in status register A.
DRV2EN (Bit 0): PS/2 mode only
0
1
0
1
IDENT
0
0
1
1
FDD interface signals are active low
FDD interface signals are active high
RWC will be active low for high data rates (typically used for 3.5" drives)
RWC will be active high for high data rates (typically used for 5.25" drives)
MFM
0
1
0
1
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W83877ATF/W83877ATG
Model 30 mode
PS/2 mode
AT mode
AT mode
Publication Release Date:November 2006
INTERFACE
Version 1.0