DESCRIPTION OF PIN FUNCTIONS
PIN
No./QFP
68:75
66
67
83
82
81
77
80
79
78
59
58
57
56
64
63
Note 1:
NAME
TOTAL
PARALLEL PORT INTERFACE (17)
Parallel Port Data Bus
8
Printer Select
1
Initiate Output
1
Auto Line Feed
1
Strobe Signal
1
Busy Signal
1
Acknowledge Handshake
1
Paper End
1
Printer Selected
1
Error at Printer
1
KEYBOARD/MOUSE INTERFACE (6)
Keyboard Data
1
Keyboard Clock
1
Mouse Data
1
Mouse Clock
1
Keyboard Reset
1
SYMBOL
PD[0:7]
nSLCTIN
nINIT
nALF
nSTROBE
BUSY
nACK
PE
SLCT
nERROR
BUFFER
TYPE
IO24
OD24/O24
OD24/O24
OD24/O24
OD24/O24
I
I
I
I
I
Note 2:
Note 3:
KDAT
IOD16P
KCLK
IOD16P
MDAT
IOD16P
MCLK
IOD16P
KBDRST
O4
(Note 3)
Gate A20
1
A20M
O4
For 12 bit addressing, SA0:SA11 only, nCS should be tied to GND. For 16 bit external
address qualification, address bits SA11:SA15 can be "ORed" together and applied to nCS.
The nCS pin functions as SA11 in full 16 bit Internal Address Qualification Mode. CR24.6
controls the FDC37M60x addressing modes.
The "n" as the first letter of a signal name indicates an "Active Low" signal.
KBDRST is active low.
Buffer Type Descriptions
I
Input, TTL compatible.
IS
Input with Schmitt trigger.
IOD16P Input/Output, 16mA sink, 90uA pull-up.
IO24
Input/Output, 24mA sink, 12mA source.
IO4
Input/Output, 4mA sink, 2mA source.
O4
Output, 4mA sink, 2mA source.
O24
Output, 24mA sink, 12mA source.
OD24
Output, Open Drain, 24mA sink.
ICLK
Clock Input
8
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