Datasheet

PIC18F2682/2685/4682/4685
DS39761C-page 18 © 2009 Microchip Technology Inc.
TABLE 1-3: PIC18F4682/4685 PINOUT I/O DESCRIPTIONS
Pin Name
Pin Number
Pin
Type
Buffer
Type
Description
PDIP QFN TQFP
MCLR
/VPP/RE3
MCLR
VPP
RE3
11818
I
P
I
ST
ST
Master Clear (input) or programming voltage (input).
Master Clear (Reset) input. This pin is an
active-low Reset to the device.
Programming voltage input.
Digital input.
OSC1/CLKI/RA7
OSC1
CLKI
RA7
13 32 30
I
I
I/O
ST
CMOS
TTL
Oscillator crystal or external clock input.
Oscillator crystal input or external clock source input.
ST buffer when configured in RC mode;
CMOS otherwise.
External clock source input. Always associated with
pin function OSC1. (See related OSC2/CLKO pin.)
General purpose I/O pin.
OSC2/CLKO/RA6
OSC2
CLKO
RA6
14 33 31
O
O
I/O
—
—
TTL
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In RC mode, OSC2 pin outputs CLKO which has 1/4
the frequency of OSC1 and denotes the instruction
cycle rate.
General purpose I/O pin.
Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output
ST = Schmitt Trigger input with CMOS levels I = Input
O = Output P = Power