ATTINY861A-SU Atmel, ATTINY861A-SU Datasheet - Page 110

• Manufacturer Part Number: ATTINY861A-SU
• Description: IC, MCU, 8BIT, 8K FLASH, 20SOIC
• Manufacturer: Atmel

Specifications of ATTINY861A-SU

• Controller Family/series: ATtiny
• No. Of I/o's: 16
• Eeprom Memory Size: 512Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 20MHz
• No.: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 8KB
• Oscillator Type: External, Internal
• Rohs Compliant: Yes

12.12 Register Description
12.12.1
110
ATtiny261A/461A/861A
TCCR1A – Timer/Counter1 Control Register A
• Bits 7,6 - COM1A1, COM1A0: Comparator A Output Mode, Bits 1 and 0
These bits control the behaviour of the Waveform Output (OCW1A) and the connection of the
Output Compare pin (OC1A). If one or both of the COM1A1:0 bits are set, the OC1A output
overrides the normal port functionality of the I/O pin it is connected to. The complementary
OC1B output is connected only in PWM modes when the COM1A1:0 bits are set to “01”. Note
that the Data Direction Register (DDR) bit corresponding to the OC1A and OC1A pins must be
set in order to enable the output driver.
The function of the COM1A1:0 bits depends on the PWM1A, WGM10 and WGM11 bit settings.
Table 12-8
(non-PWM).
Table 12-8.
Table 12-9
are set to fast PWM mode.
Table 12-9.
Bit
0x30 (0x50)
Read/Write
Initial value
COM1A1:0
COM1A1:0
00
01
10
00
01
10
11
11
shows the COM1A1:0 bit functionality when the PWM1A, WGM10 and WGM11 bits
shows the COM1A1:0 bit functionality when the PWM1A bit is set to Normal Mode
COM1A1
Compare Output Mode, Normal Mode (non-PWM)
Compare Output Mode, Fast PWM Mode
R/W
OCW1A Behaviour
Normal port operation.
Toggle on Compare Match.
Clear on Compare Match.
Set on Compare Match.
OCW1A Behaviour
Normal port operation.
Cleared on Compare Match.
Set when TCNT1 = 0x000.
Cleared on Compare Match.
Set when TCNT1 = 0x000.
Set on Compare Match
Cleared when TCNT1 = 0x000.
7
0
COM1A0
R/W
6
0
COM1B1
R/W
5
0
COM1B0
R/W
4
0
FOC1A
W
3
0
FOC1B
W
2
0
OC1A
Connected
Connected
Connected
OC1A Pin
Disconnected
Connected
Connected
Connected
Disconnected
PWM1A
R/W
1
0
PWM1B
R/W
OC1A Pin
Disconnected
Disconnected
Disconnected
OC1A
Disconnected
Connected
Disconnected
Disconnected
0
0
Disconnected
8197B–AVR–01/10
TCCR1A