4 analog comparator 3 control register - ac3con – Rainbow Electronics ATmega64C1 User Manual
Page 263

263
7647A–AVR–02/08
ATmega32/64/M1/C1
These 3 bits determine the input of the negative input of the analog comparator.
The different setting are shown in
20.4.4
Analog Comparator 3 Control Register – AC3CON
• Bit 7– AC3EN: Analog Comparator 3 Enable Bit
Set this bit to enable the analog comparator 3.
Clear this bit to disable the analog comparator 3.
• Bit 6– AC3IE: Analog Comparator 3 Interrupt Enable bit
Set this bit to enable the analog comparator 3 interrupt.
Clear this bit to disable the analog comparator 3 interrupt.
• Bit 5, 4– AC3IS1, AC3IS0: Analog Comparator 3 Interrupt Select bit
These 2 bits determine the sensitivity of the interrupt trigger.
The different setting are shown in
• Bit 3 – Res: Reserved Bit
This bit is an unused bit in the ATmega32/64/M1/C1, and will always read as zero.
• Bit 2, 1, 0– AC3M2, AC3M1, AC3M0: Analog Comparator 3 Multiplexer register
Table 20-6.
Analog Comparator 2 negative input selection
AC2M2
AC2M1
AC2M0
Description
0
0
0
“Vref”/6.40
0
0
1
“Vref”/3.20
0
1
0
“Vref”/2.13
0
1
1
“Vref”/1.60
1
0
0
Bandgap (1.1V)
1
0
1
DAC result
1
1
0
Analog Comparator Negative Input (ACMPM pin)
1
1
1
Reserved
Bit
7
6
5
4
3
2
1
0
AC3EN
AC3IE
AC3IS1
AC3IS0
-
AC3M2
AC3M1
AC3M0
AC3CON
Read/Write
R/W
R/W
R/W
R/W
-
R/W
R/W
R/W
Initial Value
0
0
0
0
0
0
0
0
Table 20-7.
Interrupt sensitivity selection
AC3IS1
AC3IS0
Description
0
0
Comparator Interrupt on output toggle
0
1
Reserved
1
0
Comparator interrupt on output falling edge
1
1
Comparator interrupt on output rising edge