attiny13-20ss ATMEL Corporation, attiny13-20ss Datasheet - Page 79

• Manufacturer Part Number: attiny13-20ss
• Description: 8-bit Microcontroller With 1k Bytes In-system Programmable Flash - Atmel Corporation
• Manufacturer: ATMEL Corporation

Analog Comparator
Multiplexed Input
Digital Input Disable Register
0 – DIDR0
2535G–AVR–01/07
It is possible to select any of the ADC3..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 ADCSRB) is set and the ADC is switched off (ADEN in ADCSRA is
zero), MUX1..0 in ADMUX select the input pin to replace the negative input to the Ana-
log Comparator, as shown in Table 35. If ACME is cleared or ADEN is set, AIN1 is
applied to the negative input to the Analog Comparator.
Table 35. Analog Comparator Multiplexed Input
• Bits 1, 0 – AIN1D, AIN0D: AIN1, AIN0 Digital Input Disable
When this bit is written logic one, the digital input buffer on the AIN1/0 pin is disabled.
The corresponding PIN Register bit will always read as zero when this bit is set. When
an analog signal is applied to the AIN1/0 pin and the digital input from this pin is not
needed, this bit should be written logic one to reduce power consumption in the digital
input buffer.
Bit
Read/Write
Initial Value
ACME
0
1
1
1
1
1
ADEN
R
7
–
0
x
1
0
0
0
0
R
6
–
0
MUX1..0
00
01
10
11
xx
xx
ADC0D
R/W
5
0
ADC2D
Analog Comparator Negative Input
AIN1
AIN1
ADC0
ADC1
ADC2
ADC3
R/W
4
0
ADC3D
R/W
3
0
ADC1D
R/W
2
0
AIN1D
R/W
1
0
AIN0D
R/W
0
0
DIDR0
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