Datasheet PIC16F8X: PIC16F83, PIC16F84, PIC16CR83, PIC16CR84 (Microchip) - 9

PIC16F8X TABLE 3-1 PIC16F8X PINOUT DESCRIPTION DIP SOIC I/O/P Buffer Pin Name Description No. No. Type Type
OSC1/CLKIN 16 16 I ST/CMOS
(3)
Oscillator crystal input/external clock source input. OSC2/CLKOUT 15 15 O — Oscillator crystal output. Connects to crystal or resonator in crystal oscillator mode. In RC mode, OSC2 pin outputs CLKOUT which has 1/4 the frequency of OSC1, and denotes the instruction cycle rate. MCLR 4 4 I/P ST Master clear (reset) input/programming voltage input. This pin is an active low reset to the device. PORTA is a bi-directional I/O port. RA0 17 17 I/O TTL RA1 18 18 I/O TTL RA2 1 1 I/O TTL RA3 2 2 I/O TTL RA4/T0CKI 3 3 I/O ST Can also be selected to be the clock input to the TMR0 timer/ counter. Output is open drain type. PORTB is a bi-directional I/O port. PORTB can be software pro- grammed for internal weak pull-up on all inputs. RB0/INT 6 6 I/O TTL/ST (
1)
RB0/INT can also be selected as an external interrupt pin. RB1 7 7 I/O TTL RB2 8 8 I/O TTL RB3 9 9 I/O TTL RB4 10 10 I/O TTL Interrupt on change pin. RB5 11 11 I/O TTL Interrupt on change pin. RB6 12 12 I/O TTL/ST
(2)
Interrupt on change pin. Serial programming clock. RB7 13 13 I/O TTL/ST
(2)
Interrupt on change pin. Serial programming data. VSS 5 5 P — Ground reference for logic and I/O pins. VDD 14 14 P — Positive supply 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 Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt. 2: This buffer is a Schmitt Trigger input when used in serial programming mode. 3: This buffer is a Schmitt Trigger input when configured in RC oscillator mode and a CMOS input otherwise.  1996-2013 Microchip Technology Inc. DS30430D-page 9