ATTINY20-XU Atmel, ATTINY20-XU Datasheet - Page 110

• Manufacturer Part Number: ATTINY20-XU
• Description: MCU AVR 2KB FLASH 12MHZ 14TSSOP
• Manufacturer: Atmel
• Series: AVR® ATtinyr

Specifications of ATTINY20-XU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 12MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 12
• Program Memory Size: 2KB (1K x 16)
• Program Memory Type: FLASH
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: *
• Processor Series: ATtiny
• Core: AVR
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: SPI, TWI
• Maximum Clock Frequency: 12 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 3.3 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Operating Temperature Range: - 40 C to + 85 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

14.2.2
110
ATtiny20
ACSRB – Analog Comparator Control and Status Register B
• Bit 4 – ACI: Analog Comparator Interrupt Flag
This bit is set by hardware when a comparator output event triggers the interrupt mode defined
by ACIS1 and ACIS0. The Analog Comparator interrupt routine is executed if the ACIE bit is set
and the I-bit in SREG is set. ACI is cleared by hardware when executing the corresponding inter-
rupt handling vector. Alternatively, ACI is cleared by writing a logic one to the flag.
• Bit 3 – ACIE: Analog Comparator Interrupt Enable
When the ACIE bit is written logic one and the I-bit in the Status Register is set, the Analog Com-
parator interrupt is activated. When written logic zero, the interrupt is disabled.
• Bit 2 – ACIC: Analog Comparator Input Capture Enable
When written logic one, this bit enables the input capture function in Timer/Counter1 to be trig-
gered by the Analog Comparator. The comparator output is then directly connected to the input
capture front-end logic, making the comparator utilize the noise canceler and edge select fea-
tures of the Timer/Counter1 Input Capture interrupt.
When written logic zero, no connection between the Analog Comparator and the input capture
function exists. To make the comparator trigger the Timer/Counter1 Input Capture inter-rupt, the
ICIE1 bit in the Timer Interrupt Mask Register (TIMSK) must be set.
• Bits 1:0 – ACIS[1:0]: Analog Comparator Interrupt Mode Select
These bits determine which comparator events that trigger the Analog Comparator interrupt. The
different settings are shown in
Table 14-2.
When changing the ACIS1/ACIS0 bits, the Analog Comparator Interrupt must be disabled by
clearing its Interrupt Enable bit in the ACSR Register. Otherwise an interrupt can occur when the
bits are changed.
• Bit 7 – HSEL: Hysteresis Select
When this bit is written logic one, the hysteresis of the analog comparator is enabled. The level
of hysteresis is selected by the HLEV bit.
Bit
0x13
Read/Write
Initial Value
ACIS1
0
0
1
1
ACIS1/ACIS0 Settings
HSEL
R/W
7
0
ACIS0
0
1
0
1
HLEV
R/W
6
0
Interrupt Mode
Comparator Interrupt on Output Toggle.
Reserved
Comparator Interrupt on Falling Output Edge.
Comparator Interrupt on Rising Output Edge.
Table
ACLP
R/W
5
0
14-2.
4
–
R
0
ACCE
R/W
3
0
ACME
R/W
2
0
ACIRS1
R/W
1
0
ACIRS0
R/W
0
0
8235B–AVR–04/11
ACSRB