ATMEGA323-8AC Atmel, ATMEGA323-8AC Datasheet - Page 56

• Manufacturer Part Number: ATMEGA323-8AC
• Description: IC AVR MCU 32K 8MHZ COM 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA323-8AC

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: ATMEGA3238AC

Timer/Counter1 Control
Register A – TCCR1A
56
ATmega323(L)
• Bits 7, 6 – COM1A1, COM1A0: Compare Output Mode1A, Bits 1 and 0
The COM1A1 and COM1A0 control bits determine any output pin action following a
Compare Match in Timer/Counter1. Any output pin actions affect pin OC1A – Output
Compare A. This is an alternative function to an I/O port, and the corresponding direc-
tion control bit must be set (one) to control an output pin. The control configuration is
shown in Table 10.
• Bits 5, 4 – COM1B1, COM1B0: Compare Output Mode1B, Bits 1 and 0
The COM1B1 and COM1B0 control bits determine any output pin action following a
Compare Match in Timer/Counter1. Any output pin actions affect pin OC1B – Output
Compare B. This is an alternative function to an I/O port, and the corresponding direc-
tion control bit must be set (one) to control an output pin. The control configuration is
shown in Table 10.
Table 17. Compare 1 Mode Select
Note:
In PWM mode, these bits have a different function. Refer to Table 22 for a description.
• Bit 3 – FOC1A: Force Output Compare 1A
Writing a logical one to this bit, forces a change in the Compare Match output pin PD5
according to the values already set in COM1A1 and COM1A0. If the COM1A1 and
COM1A0 bits are written in the same cycle as FOC1A, the new settings will not take
effect until next Compare Match or Forced Compare Match occurs. The Force Output
Compare bit can be used to change the output pin without waiting for a Compare Match
in the timer. The automatic action programmed in COM1A1 and COM1A0 happens as if
a Compare Match had occurred, but no interrupt is generated and it will not clear the
timer even if CTC1 in TCCR1B is set. The corresponding I/O pin must be set as an out-
put pin for the FOC1A bit to have effect on the pin. The FOC1A bit will always be read as
zero. The setting of the FOC1A bit has no effect in PWM mode.
• Bit 2 – FOC1B: Force Output Compare 1B
Writing a logical one to this bit, forces a change in the Compare Match output pin PD4
according to the values already set in COM1B1 and COM1B0. If the COM1B1 and
COM1B0 bits are written in the same cycle as FOC1B, the new settings will not take
effect until next Compare Match or Forced Compare Match occurs. The Force Output
Compare bit can be used to change the output pin without waiting for a Compare Match
in the timer. The automatic action programmed in COM1B1 and COM1B0 happens as if
Bit
$2F ($4F)
Read/Write
Initial Value
COM1X1
1. X = A or B.
0
0
1
1
COM1A1
R/W
7
0
COM1A0
R/W
COM1X0
6
0
0
1
0
1
COM1B1
R/W
5
0
(1)
Description
Timer/Counter1 Disconnected from Output Pin OC1X
Toggle the OC1X Output Line.
Clear the OC1X Output Line (to Zero).
Set the OC1X Output Line (to One).
COM1B0
R/W
4
0
FOC1A
R/W
3
0
FOC1B
R/W
2
0
PWM11
R/W
1
0
PWM10
1457G–AVR–09/03
R/W
0
0
TCCR1A