Datasheet
21.11.2 TC2 Control Register B
Name: TCCR2B
Offset: 0xB1
Reset: 0x00
Property: -
Bit 7 6 5 4 3 2 1 0
FOC2A FOC2B WGM2 [2] CS2[2:0]
Access
R/W R/W R/W R/W R/W R/W
Reset 0 0 0 0 0 0
Bit 7 – FOC2A Force Output Compare A
The FOC2A bit is only active when the WGM bits specify a non-PWM mode.
To ensure compatibility with future devices, this bit must be set to zero when TCCR2B is written when
operating in PWM mode. When writing a logical one to the FOC2A bit, an immediate Compare Match is
forced on the Waveform Generation unit. The OC2A output is changed according to its COM2A[1:0] bits
setting. Note that the FOC2A bit is implemented as a strobe. Therefore it is the value present in the
COM2A[1:0] bits that determines the effect of the forced compare.
A FOC2A strobe will not generate any interrupt, nor will it clear the timer in CTC mode using OCR2A as
TOP.
The FOC2A bit is always read as zero.
Bit 6 – FOC2B Force Output Compare B
The FOC2B bit is only active when the WGM bits specify a non-PWM mode.
To ensure compatibility with future devices, this bit must be set to zero when TCCR2B is written when
operating in PWM mode. When writing a logical one to the FOC2B bit, an immediate Compare Match is
forced on the Waveform Generation unit. The OC2B output is changed according to its COM2B[1:0] bits
setting. Note that the FOC2B bit is implemented as a strobe. Therefore it is the value present in the
COM2B[1:0] bits that determines the effect of the forced compare.
A FOC2B strobe will not generate any interrupt, nor will it clear the timer in CTC mode using OCR2B as
TOP.
The FOC2B bit is always read as zero.
Bit 3 – WGM2 [2] Waveform Generation Mode
Refer to TCCR2A.
Bits 2:0 – CS2[2:0] Clock Select 2 [n = 0..2]
The three Clock Select bits select the clock source to be used by the Timer/Counter.
Table 21-10. Clock Select Bit Description
CS22 CS21 CS20 Description
0 0 0 No clock source (Timer/Counter stopped).
0 0 1 clk
I/O
/1 (No prescaling)
ATmega328PB
TC2 - 8-bit Timer/Counter2 with PWM and Asynchrono...
© 2018 Microchip Technology Inc.
Datasheet Complete
DS40001906C-page 236