| Pin | Symbol | Description |
|---|
| 1 | RA2 | Bi-directional I/O port |
| 2 | RA3 | Bi-directional I/O port |
| 3 | RA4/T0CKI | Bi-directional I/O port |
| 4 | MCLR | Master Clear (Reset) input/programming voltage input. This pin is an active low RESET to the device. |
| 5 | GND | Ground reference for logic and I/O pins. |
| 6 | RB0/INT | External interrupt |
| 7 | RB1 | Bi-directional I/O port |
| 8 | RB2 | Bi-directional I/O port |
| 9 | RB3 | Bi-directional I/O port |
| 10 | RB4 | Interrupt-on-change pin. |
| 11 | RB5 | Interrupt-on-change pin. |
| 12 | RB6 | Interrupt-on-change pin, Serial programming clock |
| 13 | RB7 | Interrupt-on-change pin, Serial programming data. |
| 14 | Vcc | Positive supply for logic and I/O pins. |
| 15 | OSC2/CLKIN | 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. |
| 16 | OSC1/CLKOUT | Oscillator crystal input/external clock source input |
| 17 | RA0 | Bi-directional I/O port |
| 18 | RA1 | Bi-directional I/O port |