AT90PWM216-16SE ATMEL [ATMEL Corporation], AT90PWM216-16SE Datasheet - Page 127

• Manufacturer Part Number: AT90PWM216-16SE
• Description: 8-bit Microcontroller with 16K Bytes In-System Programmable flash
• Manufacturer: ATMEL [ATMEL Corporation]

15.10.3
7710D–AVR–08/09
Timer/Counter1 Control Register C – TCCR1C
When the ICRn is used as TOP value (see description of the WGMn3:0 bits located in the
TCCRnA and the TCCRnB Register), the ICPn is disconnected and consequently the Input Cap-
ture function is disabled.
• Bit 5 – Reserved Bit
This bit is reserved for future use. For ensuring compatibility with future devices, this bit must be
written to zero when TCCRnB is written.
• Bit 4:3 – WGMn3:2: Waveform Generation Mode
See TCCRnA Register description.
• Bit 2:0 – CSn2:0: Clock Select
The three Clock Select bits select the clock source to be used by the Timer/Counter, see
15-10
Table 15-6.
If external pin modes are used for the Timer/Countern, transitions on the Tn pin will clock the
counter even if the pin is configured as an output. This feature allows software control of the
counting.
• Bit 7 – FOCnA: Force Output Compare for Channel A
• Bit 6 – FOCnB: Force Output Compare for Channel B
The FOCnA/FOCnB bits are only active when the WGMn3:0 bits specifies a non-PWM mode.
However, for ensuring compatibility with future devices, these bits must be set to zero when
TCCRnA is written when operating in a PWM mode. When writing a logical one to the
FOCnA/FOCnB bit, an immediate compare match is forced on the Waveform Generation unit.
The OCnA/OCnB output is changed according to its COMnx1:0 bits setting. Note that the
FOCnA/FOCnB bits are implemented as strobes. Therefore it is the value present in the
COMnx1:0 bits that determine the effect of the forced compare.
Bit
Read/Write
Initial Value
CSn2
0
0
0
0
1
1
1
1
and
Figure
CSn1
0
0
1
1
0
0
1
1
Clock Select Bit Description
FOC1A
R/W
7
0
15-11.
CSn0
FOC1B
0
1
0
1
0
1
0
1
R/W
6
0
Description
No clock source (Timer/Counter stopped).
clk
clk
clk
clk
clk
External clock source on Tn pin. Clock on falling edge.
External clock source on Tn pin. Clock on rising edge.
I/O
I/O
I/O
I/O
I/O
R
5
–
0
/1 (No prescaling)
/8 (From prescaler)
/64 (From prescaler)
/256 (From prescaler)
/1024 (From prescaler)
R
4
–
0
R
3
–
0
AT90PWM216/316
R
2
–
0
R
1
–
0
R
0
–
0
TCCR1C
Figure
127