Datasheet

© 2009 Microchip Technology Inc. DS41288F-page 39
PIC16F610/616/16HV610/616
4.2.4.5 RA4/AN3
(1)
/T1G/OSC2/CLKOUT
Figure 4-4 shows the diagram for this pin. The RA4 pin
is configurable to function as one of the following:
• a general purpose I/O
• an analog input for the ADC
(1)
• a Timer1 gate (count enable)
• a crystal/resonator connection
• a clock output
FIGURE 4-4: BLOCK DIAGRAM OF RA4
Note 1: PIC16F616/16HV616 only.
VDD
VSS
D
Q
CK
Q
D
Q
CK
Q
D
Q
CK
Q
D
Q
CK
Q
VDD
D
EN
Q
D
EN
Q
Weak
Analog
Input Mode
Data Bus
WR
WPUA
RD
WPUA
RD
PORTA
WR
PORTA
WR
TRISA
RD
TRISA
WR
IOCA
RD
IOCA
F
OSC/4
To A/D Converter
(5)
Oscillator
Circuit
OSC1
CLKOUT
0
1
CLKOUT
Enable
Enable
Analog
(3)
Input Mode
RAPU
RD PORTA
To T1G
INTOSC/
RC/EC
(2)
CLK
(1)
Modes
CLKOUT
Enable
Note 1: CLK modes are XT, HS, LP, TMR1 LP and CLKOUT Enable.
2: With CLKOUT option.
3: Analog Input mode comes from ANSEL.
4: Set has priority over Reset.
5: PIC16F616/16HV616 only.
Q1
I/O Pin
Interrupt-on-
Change
S
(4)
R
Q
From other
Write ‘0’ to RAIF
RA<5, 3:0> pins