Microchip Technology MA180025 Data Sheet
2010 Microchip Technology Inc.
DS39933D-page 21
PIC18F87J90 FAMILY
TABLE 1-4:
PIC18F8XJ90 PINOUT I/O DESCRIPTIONS
Pin Name
Pin Number Pin
Type
Buffer
Type
Description
TQFP
MCLR
9
I
ST
Master Clear (input) or programming voltage (input). This
pin is an active-low Reset to the device.
pin is an active-low Reset to the device.
OSC1/CLKI/RA7
OSC1
CLKI
CLKI
RA7
49
I
I
I
I/O
CMOS
CMOS
CMOS
TTL
Oscillator crystal or external clock input.
Oscillator crystal input.
External clock source input. Always associated
with pin function, OSC1. (See related OSC1/CLKI,
OSC2/CLKO pins.)
General purpose I/O pin.
External clock source input. Always associated
with pin function, OSC1. (See related OSC1/CLKI,
OSC2/CLKO pins.)
General purpose I/O pin.
OSC2/CLKO/RA6
OSC2
CLKO
RA6
50
O
O
I/O
—
—
TTL
Oscillator crystal or clock output.
Oscillator crystal output. Connects to crystal or
resonator in Crystal Oscillator mode.
In EC modes, OSC2 pin outputs CLKO, which has
1/4 the frequency of OSC1 and denotes the
instruction cycle rate.
General purpose I/O pin.
resonator in Crystal Oscillator mode.
In EC modes, OSC2 pin outputs CLKO, which has
1/4 the frequency of OSC1 and denotes the
instruction cycle rate.
General purpose I/O pin.
PORTA is a bidirectional I/O port.
RA0/AN0
RA0
AN0
AN0
30
I/O
I
TTL
Analog
Digital I/O.
Analog Input 0.
Analog Input 0.
RA1/AN1/SEG18
RA1
AN1
SEG18
AN1
SEG18
29
I/O
I
O
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 1.
SEG18 output for LCD.
Analog Input 1.
SEG18 output for LCD.
RA2/AN2/V
REF
-
RA2
AN2
V
AN2
V
REF
-
28
I/O
I
I
I
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 2.
A/D reference voltage (low) input.
Analog Input 2.
A/D reference voltage (low) input.
RA3/AN3/V
REF
+
RA3
AN3
V
AN3
V
REF
+
27
I/O
I
I
I
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 3.
A/D reference voltage (high) input.
Analog Input 3.
A/D reference voltage (high) input.
RA4/T0CKI/SEG14
RA4
T0CKI
SEG14
T0CKI
SEG14
34
I/O
I
O
ST
ST
ST
Analog
Digital I/O.
Timer0 external clock input.
SEG14 output for LCD.
Timer0 external clock input.
SEG14 output for LCD.
RA5/AN4/SEG15
RA5
AN4
SEG15
AN4
SEG15
33
I/O
I
O
TTL
Analog
Analog
Analog
Digital I/O.
Analog Input 4.
SEG15 output for LCD.
Analog Input 4.
SEG15 output for LCD.
RA6
See the OSC2/CLKO/RA6 pin.
RA7
See the OSC1/CLKI/RA7 pin.
Legend: TTL = TTL compatible input
CMOS = CMOS compatible input or output
ST
= Schmitt Trigger input with CMOS levels
Analog = Analog input
I
= Input
O
= Output
P
= Power
OD
= Open-Drain (no P diode to V
DD
)
I
2
C™ = I
2
C/SMBus
Note 1: Default assignment for CCP2 when the CCP2MX Configuration bit is set.
2: Alternate assignment for CCP2 when the CCP2MX Configuration bit is cleared.