ADC Multiplexer Selection Register
Bit7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
REFSn[1:0] | MUXn[2:0] | ||||||
AccessR/W | R/W | R/W | R/W | R/W | |||
Reset0 | 0 | 0 | 0 | 0 |
Reference Selection [n = 1:0]
These bits select the voltage reference for the ADC. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADIF in ADCSRA is set).
REFS[1:0] | Voltage Reference Selection |
---|---|
00 | Vcc |
01 | Internal 1.1V reference |
10 | Internal 2.2V reference |
11 | Internal 4.3V reference |
Analog Channel Selection [n = 2:0]
The value of these bits selects which analog inputs are connected to the ADC. If these bits are changed during a conversion, the change will not go in effect until this conversion is complete (ADCSRA.ADIF is set).
MUX[2:0] | Single Ended Input | Pin name |
---|---|---|
000 | ADC0 | PA[0] |
001 | ADC1 | PA[1] |
010 | ADC2 | PA[5] |
011 | ADC3 | PA[6] |
100 | ADC4 | PB[0] |
101 | ADC5 | PB[1] |
110 | ADC6 | PB[2] |
111 | ADC7 | PB[3] |