ATmega88PA Automotive Atmel Corporation, ATmega88PA Automotive Datasheet - Page 160

• Manufacturer Part Number: ATmega88PA Automotive
• Manufacturer: Atmel Corporation

160
Atmel ATmega48PA/88PA/168PA [Preliminary]
Table 18-7
correct PWM mode.
Table 18-7.
• Bits 3, 2 – Reserved
These bits are reserved bits in the Atmel
zero.
• Bits 1:0 – WGM21:0: Waveform Generation Mode
Combined with the WGM22 bit found in the TCCR2B Register, these bits control the counting
sequence of the counter, the source for maximum (TOP) counter value, and what type of
waveform generation to be used, see
Timer/Counter unit are: Normal mode (counter), Clear Timer on Compare Match (CTC) mode,
and two types of Pulse Width Modulation (PWM) modes (see
149).
Table 18-8.
Note:
Notes:
Mode
COM2B1
0
1
2
3
4
5
6
7
0
0
1
1
1. A special case occurs when OCR2B equals TOP and COM2B1 is set. In this case, the
1. MAX = 0xFF
2. BOTTOM = 0x00
WGM2
shows the COM2B1:0 bit functionality when the WGM22:0 bits are set to phase
Compare Match is ignored, but the set or clear is done at TOP. See
Mode” on page 152
0
0
0
0
1
1
1
1
Compare Output Mode, Phase Correct PWM Mode
Waveform Generation Mode Bit Description
COM2B0
WGM1
0
1
0
1
0
0
1
1
0
0
1
1
Description
Normal port operation, OC2B disconnected.
Reserved
Clear OC2B on Compare Match when up-counting. Set OC2B on
Compare Match when down-counting.
Set OC2B on Compare Match when up-counting. Clear OC2B on
Compare Match when down-counting.
WGM0
for more details.
0
1
0
1
0
1
0
1
Timer/Counter
Mode of Operation
Normal
PWM, Phase
Correct
CTC
Fast PWM
Reserved
PWM, Phase
Correct
Reserved
Fast PWM
®
Table
ATmega48PA/88PA/168PA and will always read as
18-8. Modes of operation supported by the
OCRA
OCRA
OCRA
0xFF
0xFF
0xFF
TOP
–
–
“Modes of Operation” on page
(1)
Immediate
Immediate
Update of
BOTTOM
BOTTOM
OCRx at
TOP
TOP
“Phase Correct PWM
–
–
9223B–AVR–09/11
Set on
TOV Flag
BOTTOM
BOTTOM
MAX
MAX
MAX
TOP
–
–
(1)(2)