
PIC17C4X
DS30412B-page 12
1996 Microchip Technology Inc.
TABLE 3-1:
PINOUT DESCRIPTIONS
Name
DIP
No.
19
PLCC
No.
21
QFP
No.
37
I/O/P
Type
I
Buffer
Type
ST
Description
OSC1/CLKIN
Oscillator input in crystal/resonator or RC oscillator mode.
External clock input in external clock mode.
Oscillator output. Connects to crystal or resonator in crystal
oscillator mode. In RC oscillator or external clock modes
OSC2 pin outputs CLKOUT which has one fourth the fre-
quency of OSC1 and denotes the instruction cycle rate.
Master clear (reset) input/Programming Voltage (V
This is the active low reset input to the chip.
PORTA is a bi-directional I/O Port except for RA0 and RA1
which are input only.
RA0/INT can also be selected as an external interrupt
input. Interrupt can be configured to be on positive or
negative edge.
RA1/T0CKI can also be selected as an external interrupt
input, and the interrupt can be configured to be on posi-
tive or negative edge. RA1/T0CKI can also be selected
to be the clock input to the Timer0 timer/counter.
High voltage, high current, open drain input/output port
pins.
High voltage, high current, open drain input/output port
pins.
RA4/RX/DT can also be selected as the USART (SCI)
Asynchronous Receive or USART (SCI) Synchronous
Data.
RA5/TX/CK can also be selected as the USART (SCI)
Asynchronous Transmit or USART (SCI) Synchronous
Clock.
PORTB is a bi-directional I/O Port with software configurable
weak pull-ups.
RB0/CAP1 can also be the CAP1 input pin.
RB1/CAP2 can also be the CAP2 input pin.
RB2/PWM1 can also be the PWM1 output pin.
RB3/PWM2 can also be the PWM2 output pin.
RB4/TCLK12 can also be the external clock input to
Timer1 and Timer2.
RB5/TCLK3 can also be the external clock input to
Timer3.
OSC2/CLKOUT
20
22
38
O
—
MCLR/V
PP
32
35
7
I/P
ST
PP
) input.
RA0/INT
26
28
44
I
ST
RA1/T0CKI
25
27
43
I
ST
RA2
24
26
42
I/O
ST
RA3
23
25
41
I/O
ST
RA4/RX/DT
22
24
40
I/O
ST
RA5/TX/CK
21
23
39
I/O
ST
RB0/CAP1
RB1/CAP2
RB2/PWM1
RB3/PWM2
RB4/TCLK12
11
12
13
14
15
13
14
15
16
17
29
30
31
32
33
I/O
I/O
I/O
I/O
I/O
ST
ST
ST
ST
ST
RB5/TCLK3
16
18
34
I/O
ST
RB6
RB7
17
18
19
20
35
36
I/O
I/O
ST
ST
PORTC is a bi-directional I/O Port.
This is also the lower half of the 16-bit wide system bus
in microprocessor mode or extended microcontroller
mode. In multiplexed system bus configuration, these
pins are address output as well as data input or output.
RC0/AD0
RC1/AD1
RC2/AD2
RC3/AD3
RC4/AD4
RC5/AD5
RC6/AD6
RC7/AD7
Legend: I = Input only; O = Output only; I/O = Input/Output; P = Power; — = Not Used; TTL = TTL input;
ST = Schmitt Trigger input.
2
3
4
5
6
7
8
9
3
4
5
6
7
8
9
10
19
20
21
22
23
24
25
26
I/O
I/O
I/O
I/O
I/O
I/O
I/O
I/O
TTL
TTL
TTL
TTL
TTL
TTL
TTL
TTL