PIC18F24 MICROCHIP [Microchip Technology], PIC18F24 Datasheet - Page 243

• Manufacturer Part Number: PIC18F24
• Description: 28/40-Pin High-Performance, Enhanced Flash Microcontrollers with CAN Module
• Manufacturer: MICROCHIP [Microchip Technology]

20.0
The Analog-to-Digital (A/D) Converter module has five
inputs for the PIC18F2X8 devices and eight for the
PIC18F4X8 devices. This module has the ADCON0
and ADCON1 register definitions that are compatible
with the PICmicro
The A/D allows conversion of an analog input signal to
a corresponding 10-bit digital number.
REGISTER 20-1:
 2004 Microchip Technology Inc.
COMPATIBLE 10-BIT ANALOG-
TO-DIGITAL CONVERTER (A/D)
MODULE
bit 7-6
bit 5-3
bit 2
bit 1
bit 0
®
mid-range A/D module.
ADCON0: A/D CONTROL REGISTER 0
ADCS1:ADCS0: A/D Conversion Clock Select bits (ADCON0 bits in bold)
CHS2:CHS0: Analog Channel Select bits
000 = Channel 0 (AN0)
001 = Channel 1 (AN1)
010 = Channel 2 (AN2)
011 = Channel 3 (AN3)
100 = Channel 4 (AN4)
101 = Channel 5 (AN5)
110 = Channel 6 (AN6)
111 = Channel 7 (AN7)
GO/DONE: A/D Conversion Status bit
When ADON = 1:
1 = A/D conversion in progress (setting this bit starts the A/D conversion which is automatically
0 = A/D conversion not in progress
Unimplemented: Read as ‘0’
ADON: A/D On bit
1 = A/D converter module is powered up
0 = A/D converter module is shut-off and consumes no operating current
bit 7
Legend:
R = Readable bit
-n = Value at POR
ADCS1
R/W-0
Note 1: These channels are unimplemented on PIC18F2X8 (28-pin) devices. Do not select
<ADCS2>
ADCON1
cleared by hardware when the A/D conversion is complete)
0
0
0
0
1
1
1
1
any unimplemented channel.
ADCS0
R/W-0
<ADCS1:ADCS0>
ADCON0
00
01
10
11
00
01
10
11
(1)
(1)
(1)
R/W-0
CHS2
W = Writable bit
‘1’ = Bit is set
F
F
F
F
F
F
F
F
OSC
OSC
OSC
RC
OSC
OSC
OSC
RC
R/W-0
CHS1
(clock derived from the internal A/D RC oscillator)
(clock derived from the internal A/D RC oscillator)
/2
/8
/32
/4
/16
/64
The A/D module has four registers. These registers are:
• A/D Result High Register (ADRESH)
• A/D Result Low Register (ADRESL)
• A/D Control Register 0 (ADCON0)
• A/D Control Register 1 (ADCON1)
The ADCON0 register, shown in Register 20-1,
controls the operation of the A/D module. The
ADCON1 register, shown in Register 20-2, configures
the functions of the port pins.
R/W-0
CHS0
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
Clock Conversion
GO/DONE
R/W-0
PIC18FXX8
x = Bit is unknown
U-0
DS41159D-page 241
—
ADON
R/W-0
bit 0