atmega32u4-16mu ATMEL Corporation, atmega32u4-16mu Datasheet - Page 186

• Manufacturer Part Number: atmega32u4-16mu
• Description: Atmega32u4 8-bit Avr Microcontroller With 32k Bytes Of Isp Flash And Usb Controller
• Manufacturer: ATMEL Corporation

186
ATmega32U4
• Bits 5,4 - COM4B1S, COM4B0S: Comparator B Output Mode, Bits 1 and 0
These bits are the shadow bits of the COM4A1 and COM4A0 bits that are described in the sec-
tion
• Bits 3,2 - COM4D1, COM4D0: Comparator D Output Mode, Bits 1 and 0
These bits control the behavior of the Waveform Output (OCW4D) and the connection of the
Output Compare pin (OC4D). If one or both of the COM4D1:0 bits are set, the OC4D output
overrides the normal port functionality of the I/O pin it is connected to. The complementary
OC4D output is connected only in PWM modes when the COM4D1:0 bits are set to “01”. Note
that the Data Direction Register (DDR) bit corresponding to the OC4D pin must be set in order to
enable the output driver.
The function of the COM4D1:0 bits depends on the PWM4D and WGM40 bit settings.
16
PWM).
Table 16-16. Compare Output Mode, Normal Mode (non-PWM)
Table 16-17
to Fast PWM Mode.
Table 16-17. Compare Output Mode, Fast PWM Mode
Table 16-18 on page 187
bits are set to Phase and Frequency Correct PWM Mode.
COM4D1..0
COM4D1..0
shows the COM4D1:0 bit functionality when the PWM4D bit is set to a Normal Mode (non-
“TCCR4A – Timer/Counter4 Control Register A” on page
00
01
10
00
01
10
11
11
shows the COM4D1:0 bit functionality when the PWM4D and WGM40 bits are set
OCW4D Behavior
Normal port operation.
Toggle on Compare Match.
Clear on Compare Match.
Set on Compare Match.
OCW4D Behavior
Normal port operation.
Cleared on Compare Match.
Set when TCNT4 = 0x000.
Cleared on Compare Match.
Set when TCNT4 = 0x000.
Set on Compare Match.
Clear when TCNT4 = 0x000.
shows the COM4D1:0 bit functionality when the PWM4D and WGM40
181.
Disconnected
Disconnected
Connected
Connected
Connected
Connected
Connected
Connected
OC4D Pin
OC4D Pin
Disconnected
Disconnected
Disconnected
Disconnected
Disconnected
Disconnected
Disconnected
7766A–AVR–03/08
Connected
OC4D Pin
OC4D Pin
Table 16-