PIC16C7X
TABLE 3-2:
PIC16C73/73A/76 PINOUT DESCRIPTION
DIP
Pin#
SOIC
Pin#
I/O/P
Type
Buffer
Type
Pin Name
Description
(3)
OSC1/CLKIN
9
9
I
Oscillator crystal input/external clock source input.
ST/CMOS
—
OSC2/CLKOUT
10
10
O
Oscillator crystal output. Connects to crystal or resonator in
crystal oscillator mode. In RC mode, the OSC2 pin outputs
CLKOUT which has 1/4 the frequency of OSC1, and denotes
the instruction cycle rate.
1
1
I/P
ST
Master clear (reset) input or programming voltage input. This
pin is an active low reset to the device.
MCLR/VPP
PORTA is a bi-directional I/O port.
RA0 can also be analog input0
RA0/AN0
2
3
4
5
6
2
3
4
5
6
I/O
I/O
I/O
I/O
I/O
TTL
TTL
TTL
TTL
ST
RA1/AN1
RA1 can also be analog input1
RA2/AN2
RA2 can also be analog input2
RA3/AN3/VREF
RA4/T0CKI
RA3 can also be analog input3 or analog reference voltage
RA4 can also be the clock input to the Timer0 module.
Output is open drain type.
RA5/SS/AN4
7
7
I/O
TTL
RA5 can also be analog input4 or the slave select for the
synchronous serial port.
PORTB is a bi-directional I/O port. PORTB can be software
programmed for internal weak pull-up on all inputs.
(1)
RB0/INT
RB1
21
22
23
24
25
26
27
28
21
22
23
24
25
26
27
28
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
TTL/ST
TTL
RB0 can also be the external interrupt pin.
RB2
TTL
RB3
TTL
RB4
TTL
Interrupt on change pin.
RB5
TTL
Interrupt on change pin.
(2)
RB6
TTL/ST
TTL/ST
Interrupt on change pin. Serial programming clock.
Interrupt on change pin. Serial programming data.
PORTC is a bi-directional I/O port.
(2)
RB7
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
RC2/CCP1
11
12
13
14
15
11
12
13
14
15
I/O
I/O
I/O
I/O
I/O
ST
ST
ST
ST
ST
RC0 can also be the Timer1 oscillator output or Timer1
clock input.
RC1 can also be the Timer1 oscillator input or Capture2
input/Compare2 output/PWM2 output.
RC2 can also be the Capture1 input/Compare1 output/
PWM1 output.
RC3/SCK/SCL
RC4/SDI/SDA
RC3 can also be the synchronous serial clock input/output
2
for both SPI and I C modes.
RC4 can also be the SPI Data In (SPI mode) or
2
data I/O (I C mode).
RC5/SDO
16
17
16
17
I/O
I/O
ST
ST
RC5 can also be the SPI Data Out (SPI mode).
RC6/TX/CK
RC6 can also be the USART Asynchronous Transmit or
Synchronous Clock.
RC7/RX/DT
18
18
I/O
ST
RC7 can also be the USART Asynchronous Receive or
Synchronous Data.
VSS
8, 19
20
8, 19
20
P
P
—
—
Ground reference for logic and I/O pins.
Positive supply for logic and I/O pins.
VDD
Legend: I = input
O = output
— = Not used
I/O = input/output
TTL = TTL input
P = power
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.
DS30390E-page 14
1997 Microchip Technology Inc.
MICROCHIP [ MICROCHIP ]
