DESCRIPTION OF PIN FUNCTIONS
BUFFER
QFP/
TQFP
PIN NO.
TYPE
NAME
Ground
SYMBOL
DESCRIPTION
Ground Supply.
6,47,
GND
67,95
Note 1:Refer to Configuration Register 00 for information on the pull-ups for these pins!
Note IDE does not decode for 377, 3F7
Note RI and the Serial interrupt is always active if system power is applied to the chip.
BUFFER TYPE DESCRIPTIONS
BUFFER TYPE
I/O24
O24
DESCRIPTION
Input/Output. 24 mA sink; 12 mA source
Output. 24 mA sink; 12 mA source
Open drain. 48 mA sink
OD48
O4
Output. 4 mA sink; 2 mA source
Output. 24 mA sink
OD24
OD24P
OP24
024P
OCLK
ICLK
Open drain. 24 mA sink; 30μA source
Output. 24 mA sink; 4 mA source
Output. 24 mA sink; 12 mA source; with 30μA pull-up
Output to external crystal
Input to Crystal Oscillator Circuit (CMOS levels)
Input TTL compatible.
I
IS
Input with Schmitt Trigger.
15
SMSC [ SMSC CORPORATION ]
