AT90CAN128-15AZ Datasheet, PDF (137/431 Pages) ATMEL Corporation – 8-bit Microcontroller with 32K/64K/128K Bytes of ISP Flash and CAN Controller

AT90CAN32/64/128
Table 13-3 shows the COMnx1:0 bit functionality when the WGMn3:0 bits are set to the phase
correct or the phase and frequency correct, PWM mode.
Table 13-3. Compare Output Mode, Phase Correct and Phase and Frequency Correct
PWM⁽¹⁾
COMnA1/COMnB1/
COMnC1
COMnA0/COMnB0/
COMnC0
Description
0
0
Normal port operation, OCnA/OCnB/OCnC
disconnected.
WGMn3=0: Normal port operation,
0
1
OCnA/OCnB/OCnC disconnected.
WGMn3=1: Toggle OCnA on Compare Match,
OCnB/OCnC reserved.
Clear OCnA/OCnB/OCnC on Compare Match when
up-counting.
1
0
Set OCnA/OCnB/OCnC on Compare Match when
downcounting.
Set OCnA/OCnB/OCnC on Compare Match when up-
counting.
1
1
Clear OCnA/OCnB/OCnC on Compare Match when
downcounting.
Note:
1. A special case occurs when OCnA/OCnB/OCnC equals TOP and
COMnA1/COMnB1/COMnC1 is set. See “Phase Correct PWM Mode” on page 130. for more
details.
• Bit 1:0 – WGMn1:0: Waveform Generation Mode
Combined with the WGMn3:2 bits found in the TCCRnB Register, these bits control the counting
sequence of the counter, the source for maximum (TOP) counter value, and what type of wave-
form generation to be used, see Table 13-4. Modes of operation supported by the Timer/Counter
unit are: Normal mode (counter), Clear Timer on Compare match (CTC) mode, and three types
of Pulse Width Modulation (PWM) modes. (See “Modes of Operation” on page 126.).
7682C–AUTO–04/08
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