AT90PWM2B-16SE ATMEL [ATMEL Corporation], AT90PWM2B-16SE Datasheet - Page 122

• Manufacturer Part Number: AT90PWM2B-16SE
• Description: 8-bit Microcontroller with 8K Bytes In-System Programmable Flash
• Manufacturer: ATMEL [ATMEL Corporation]

15.10 16-bit Timer/Counter Register Description
15.10.1
122
AT90PWM2/3/2B/3B
Timer/Counter1 Control Register A – TCCR1A
Figure 15-12. Timer/Counter Timing Diagram, no Prescaling
Figure 15-13
Figure 15-13. Timer/Counter Timing Diagram, with Prescaler (f
• Bit 7:6 – COMnA1:0: Compare Output Mode for Channel A
• Bit 5:4 – COMnB1:0: Compare Output Mode for Channel B
The COMnA1:0 and COMnB1:0 control the Output Compare pins (OCnA and OCnB respec-
tively) behavior. If one or both of the COMnA1:0 bits are written to one, the OCnA output
overrides the normal port functionality of the I/O pin it is connected to. If one or both of the
COMnB1:0 bit are written to one, the OCnB output overrides the normal port functionality of the
Bit
Read/Write
Initial Value
and ICF n
(PC and PFC PWM)
and ICFn
(CTC and FPWM)
TOVn
(Update at TOP)
(PC and PFC PWM)
TOVn
(CTC and FPWM)
(Update at TOP)
TCNTn
TCNTn
OCRnx
as TOP)
(clk
TCNTn
TCNTn
OCRnx
(clk
as TOP)
clk
clk
clk
clk
I/O
(FPWM)
I/O
shows the same timing data, but with the prescaler enabled.
(FPWM)
I/O
Tn
I/O
Tn
/8)
COM1A1
(if used
/1)
(if used
R/W
7
0
COM1A0
R/W
6
0
TOP - 1
TOP - 1
TOP - 1
TOP - 1
Old OCRnx Value
Old OCRnx Value
COM1B1
R/W
5
0
COM1B0
R/W
4
0
TOP
TOP
TOP
TOP
R
3
–
0
BOTTOM
BOTTOM
TOP - 1
TOP - 1
clk_I/O
R
2
0
–
New OCRnx Value
New OCRnx Value
/8)
WGM11
R/W
1
0
BOTTOM + 1
BOTTOM + 1
TOP - 2
TOP - 2
WGM10
R/W
0
0
4317J–AVR–08/10
TCCR1A