ATMEGA48V_11 ATMEL [ATMEL Corporation], ATMEGA48V_11 Datasheet - Page 104

• Manufacturer Part Number: ATMEGA48V_11
• Description: 8-bit Atmel Microcontroller with 4/8/16K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

15.9.2
2545T–AVR–05/11
TCCR0B – Timer/counter control register B
• Bit 7 – FOC0A: Force output compare A
The FOC0A bit is only active when the WGM bits specify a non-PWM mode.
However, for ensuring compatibility with future devices, this bit must be set to zero when
TCCR0B is written when operating in PWM mode. When writing a logical one to the FOC0A bit,
an immediate Compare Match is forced on the Waveform Generation unit. The OC0A output is
changed according to its COM0A1:0 bits setting. Note that the FOC0A bit is implemented as a
strobe. Therefore it is the value present in the COM0A1:0 bits that determines the effect of the
forced compare.
A FOC0A strobe will not generate any interrupt, nor will it clear the timer in CTC mode using
OCR0A as TOP.
The FOC0A bit is always read as zero.
• Bit 6 – FOC0B: Force output compare B
The FOC0B bit is only active when the WGM bits specify a non-PWM mode.
However, for ensuring compatibility with future devices, this bit must be set to zero when
TCCR0B is written when operating in PWM mode. When writing a logical one to the FOC0B bit,
an immediate Compare Match is forced on the Waveform Generation unit. The OC0B output is
changed according to its COM0B1:0 bits setting. Note that the FOC0B bit is implemented as a
strobe. Therefore it is the value present in the COM0B1:0 bits that determines the effect of the
forced compare.
A FOC0B strobe will not generate any interrupt, nor will it clear the timer in CTC mode using
OCR0B as TOP.
The FOC0B bit is always read as zero.
• Bits 5:4 – Res: Reserved bits
These bits are reserved bits in the Atmel ATmega48/88/168 and will always read as zero.
• Bit 3 – WGM02: Waveform generation mode
See the description in the
• Bits 2:0 – CS02:0: Clock select
The three Clock Select bits select the clock source to be used by the Timer/Counter.
Bit
0x25 (0x45)
Read/write
Initial value
FOC0A
W
7
0
FOC0B
“TCCR0A – Timer/counter control register A” on page
W
6
0
R
5
–
0
R
4
–
0
WGM02
R/W
3
0
ATmega48/88/168
CS02
R/W
2
0
CS01
R/W
1
0
CS00
R/W
101.
0
0
TCCR0B
104