ATA6613 ATMEL Corporation, ATA6613 Datasheet - Page 177

• Manufacturer Part Number: ATA6613
• Description: Ata6613
• Manufacturer: ATMEL Corporation

6.15.8.2
9111C–AUTO–02/08
Timer/Counter Control Register B – TCCR2B
• Bit 7 – FOC2A: Force Output Compare A
• Bit 6 – FOC2B: Force Output Compare B
• Bits 5:4 – Res: Reserved Bits
• Bit 3 – WGM22: Waveform Generation Mode
• Bit 2:0 – CS22:0: Clock Select
Initial Value
Read/Write
The FOC2A 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
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 COM2A1:0 bits setting. Note that the FOC2A bit is imple-
mented as a strobe. Therefore it is the value present in the COM2A1:0 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.
The FOC2B 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
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 COM2B1:0 bits setting. Note that the FOC2B bit is imple-
mented as a strobe. Therefore it is the value present in the COM2B1:0 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.
These bits are reserved bits in the ATA6612/ATA6613 and will always read as zero.
See the description in
The three Clock Select bits select the clock source to be used by the Timer/Counter (see
Table 6-65 on page
Bit
FOC2A
W
7
0
FOC2B
178).
W
“Timer/Counter Control Register A – TCCR2A” on page
6
0
R
5
–
0
R
4
–
0
WGM22
R
3
0
ATA6612/ATA6613
CS22
R
2
0
CS21
R/W
1
0
CS20
R/W
0
0
174.
TCCR2B
177