Datasheet

 1996-2013 Microchip Technology Inc. Preliminary DS40143E-page 11
PIC16C55X
TABLE 3-1: PIC16C55X PINOUT DESCRIPTION
Name
Pin Number
Pin
Type
Buffer
Type
PDIP SOIC SSOP Description
OSC1/CLKIN 16 16 18 I ST/CMOS Oscillator crystal input/external clock source output.
OSC2/CLKOUT 15 15 17 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
/VPP 4 4 4 I/P ST Master clear (Reset) input/programming voltage input.
This pin is an active low RESET to the device.
RA0 17 17 19 I/O ST Bi-directional I/O port
RA1 18 18 20 I/O ST Bi-directional I/O port
RA2 1 1 1 I/O ST Bi-directional I/O port
RA3 2 2 2 I/O ST Bi-directional I/O port
RA4/T0CKI 3 3 3 I/O ST Bi-directional I/O port or external clock input for TMR0.
Output is open drain type.
RB0/INT 6 6 7 I/O TTL/ST
(1)
Bi-directional I/O port can be software programmed for
internal weak pull-up. RB0/INT can also be selected as an
external interrupt pin.
RB1 7 7 8 I/O TTL Bi-directional I/O port can be software programmed for
internal weak pull-up.
RB2 8 8 9 I/O TTL Bi-directional I/O port can be software programmed for
internal weak pull-up.
RB3 9 9 10 I/O TTL Bi-directional I/O port can be software programmed for
internal weak pull-up.
RB4 10 10 11 I/O TTL Bi-directional I/O port can be software programmed for
internal weak pull-up. Interrupt-on-change pin.
RB5 11 11 12 I/O TTL Bi-directional I/O port can be software programmed for
internal weak pull-up. Interrupt-on-change pin.
RB6 12 12 13 I/O TTL/ST
(2)
Bi-directional I/O port can be software programmed for
internal weak pull-up. Interrupt-on-change pin. Serial pro-
gramming clock.
RB7 13 13 14 I/O TTL/ST
(2)
Bi-directional I/O port can be software programmed for
internal weak pull-up. Interrupt-on-change pin. Serial pro-
gramming data.
RC0
(3)
18 18 18 I/O TTL Bi-directional I/O port input buffer.
RC1
(3)
19 19 19 I/O TTL Bi-directional I/O port input buffer.
RC2
(3)
20 20 20 I/O TTL Bi-directional I/O port input buffer.
RC3
(3)
21 21 21 I/O TTL Bi-directional I/O port input buffer.
RC4
(3)
22 22 22 I/O TTL Bi-directional I/O port input buffer.
RC5
(3)
23 23 23 I/O TTL Bi-directional I/O port input buffer.
RC6
(3)
24 24 24 I/O TTL Bi-directional I/O port input buffer.
RC7
(3)
25 25 25 I/O TTL Bi-directional I/O port input buffer.
V
SS 5 5 5,6 P — Ground reference for logic and I/O pins.
V
DD 14 14 15,16 P — Positive supply for logic and I/O pins.
Legend: O = Output I/O = Input/output P = Power
— = Not used I = Input ST = Schmitt Trigger input
TTL = TTL 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: PIC16C557 only.