DESCRIPTION OF PIN FUNCTIONS
BUFFER
QFP/
TQFP
PIN NO.
TYPE
NAME
SYMBOL
DESCRIPTION
Positive Supply Voltage.
Ground Supply.
15,72 Power
VCC
6,47,
Ground
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
DESCRIPTION
Input/Output. 24 mA sink; 12 mA source
Output. 24 mA sink; 12 mA source
Open drain. 48 mA sink
BUFFER TYPE
I/O24
O24
OD48
O4
Output. 4 mA sink; 2 mA source
Output. 24 mA sink
OD24
OD24P
OP24
024P
OCLK
ICLK
Open drain. 24 mA sink; 30 A source
m
Output. 24 mA sink; 4 mA source
Output. 24 mA sink; 12 mA source; with 30 A pull-up
m
Output to external crystal
Input to Crystal Oscillator Circuit (CMOS levels)
Input TTL compatible.
I
IS
Input with Schmitt Trigger.
15
SMSC [ SMSC CORPORATION ]
