Datasheet

© 2005 Microchip Technology Inc. Preliminary DS41236B-page 11
PIC12F508/509/16F505
TABLE 3-2: PIC12F508/509 PINOUT DESCRIPTION
Name Function
Input
Type
Output
Type
Description
GP0/ICSPDAT GP0 TTL CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPDAT ST CMOS In-Circuit Serial Programming™ data pin.
GP1\ICSPCLK GP1 TTL CMOS Bidirectional I/O pin. Can be software programmed for internal
weak pull-up and wake-up from Sleep on pin change.
ICSPCLK ST CMOS In-Circuit Serial Programming clock pin.
GP2/T0CKI GP2 TTL CMOS Bidirectional I/O pin.
T0CKI ST — Clock input to TMR0.
GP3/MCLR/VPP GP3 TTL — Input pin. Can be software programmed for internal weak
pull-up and wake-up from Sleep on pin change.
MCLR
ST — Master Clear (Reset). When configured as MCLR, this pin is
an active-low Reset to the device. Voltage on MCLR
/VPP must
not exceed V
DD during normal device operation or the device
will enter Programming mode. Weak pull-up always on if
configured as MCLR
.
V
PP HV — Programming voltage input.
GP4/OSC2 GP4 TTL CMOS Bidirectional I/O pin.
OSC2 — XTAL Oscillator crystal output. Connections to crystal or resonator in
Crystal Oscillator mode (XT and LP modes only, GPIO in other
modes).
GP5/OSC1/CLKIN GP5 TTL CMOS Bidirectional I/O pin.
OSC1 XTAL — Oscillator crystal input.
CLKIN ST — External clock source input.
V
DD VDD — P Positive supply for logic and I/O pins.
V
SS VSS — P Ground reference for logic and I/O pins.
Legend: I = Input, O = Output, I/O = Input/Output, P = Power, — = Not used, TTL = TTL input,
ST = Schmitt Trigger input