Rainbow Electronics ATmega128L - Manual (Page 220)

220
ATmega128(L)
2467B–09/01
Analog Comparator
Multiplexed Input It is possible to select any of the ADC7..0 pins to replace the negative input to the ana-
log comparator. The ADC multiplexer is used to select this input, and consequently, the
ADC must be switched off to utilize this feature. If the Analog Comparator Multiplexer
Enable bit (ACME in SFIOR) is set and the ADC is switched off (ADEN in ADCSRA is
zero), MUX2..0 in ADMUX select the input pin to replace the negative input to the Ana-
log Comparator, as shown in
Table 93. If ACME is cleared or ADEN is set, AIN1 is
applied to the negative input to the Analog Comparator.
Table 93. Analog Comparator Multiplexed Input
ACME ADEN MUX2..0 Analog Comparator Negative Input
0 x xxx AIN1
1 1 xxx AIN1
1 0 000 ADC0
1 0 001 ADC1
1 0 010 ADC2
1 0 011 ADC3
1 0 100 ADC4
1 0 101 ADC5
1 0 110 ADC6
1 0 111 ADC7