Description of Multifunction Pins
PIN
ORIGINAL
ALTERNATE
FUNCTION 1
8042 P16
8042 P12
8042 P16
8042 P12
IRRX
IRTX
SA15
SA12
SA13
NO./QFP FUNCTION
DEFAULT
nDACK3
DRQ3
nRI2
nDCD2
RXD2
NOTE
nDACK3
DRQ3
nRI2
nDCD2
RXD2
1
1
2
2
3
3
4
4
4
4
51
52
92
94
95
96
97
98
99
100
TXD2
TXD2
nDSR2
nRTS2
nCTS2
nDTR2
nDSR2
nRTS2
nCTS2
nDTR2
SA14
Note 1: Controlled by DMA3SEL(LD8:CRC0.1)
Note 2: Controlled by 8042COMSEL(LD8:CRC0.3)
Note 3: Controlled by IR Option Register( LD5:CRF1.6)
Note 4: Controlled by 16 bit Address Qualification (CR24.6)
For more information, refer to tables 63 through 73.
REFERENCE DOCUMENTS
1. IEEE 1284 Extended Capabilities Port Protocol and ISA Standard, Rev. 1.14, July 14, 1993.
2. Hardware Description of the 8042, Intel 8 bit Embedded Controller Handbook.
3. PCI Bus Power Management Interface Specification, Rev. 1.0, Draft, March 18, 1997.
10
SMSC [ SMSC CORPORATION ]
