w83977eg Winbond Electronics Corp America, w83977eg Datasheet - Page 63

• Manufacturer Part Number: w83977eg
• Description: Winbond Isa I/o W83977ef W83977eg
• Manufacturer: Winbond Electronics Corp America

Bit 7: This bit reflects the complement of the Busy input.
Bit 6: This bit reflects the nAck input.
Bit 5: This bit reflects the PError input.
Bit 4: This bit reflects the Select input.
Bit 3: This bit reflects the nFault input.
Bit 2-0: These three bits are not implemented and are always logic one during a read.
7.3.4
The bit definitions are as follows:
Bit 6, 7: These two bits are logic one during a read and cannot be written.
Bit 5: This bit has no effect and the direction is always out if mode = 000 or mode = 010. Direction is
Bit 4: Interrupt request enable. When this bit is set to a high level, it may be used to enable interrupt
Bit 3: This bit is inverted and output to the SLIN# output.
Bit 2: This bit is output to the
Bit 1: This bit is inverted and output to the
Bit 0: This bit is inverted and output to the
requests from the parallel port to the CPU due to a low to high transition on the
valid in all other modes.
0
1
0
1
Device Control Register (DCR)
the parallel port is in output mode.
the parallel port is in input mode.
The printer is not selected.
The printer is selected.
7
INIT#
1
6
1
output.
5
AFD#
STB#
4
W83977EF-AW/W83977EG-AW
3
output.
output.
-61-
2
1
0
strobe
autofd
nInit
SelectIn
ackIntEn
Direction
Publication Release Date: Apr. 2006
ACK#
Revision 1.2
input.