ATMEGA2561-16AI Atmel, ATMEGA2561-16AI Datasheet - Page 180
ATMEGA2561-16AI
Manufacturer Part Number
ATMEGA2561-16AI
Description
IC AVR MCU 256K 16MHZ 64TQFP
Manufacturer
Atmel
Series
AVR® ATmegar
Specifications of ATMEGA2561-16AI
Core Processor
AVR
Core Size
8-Bit
Speed
16MHz
Connectivity
EBI/EMI, I²C, SPI, UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
54
Program Memory Size
256KB (128K x 16)
Program Memory Type
FLASH
Eeprom Size
4K x 8
Ram Size
8K x 8
Voltage - Supply (vcc/vdd)
4.5 V ~ 5.5 V
Data Converters
A/D 8x10b
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Package / Case
64-TQFP, 64-VQFP
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
- Current page: 180 of 444
- Download datasheet (10Mb)
19.5
2549M–AVR–09/10
Output Compare Unit
The Timer/Counter Overflow Flag (TOV2) is set each time the counter reaches BOTTOM. The
Interrupt Flag can be used to generate an interrupt each time the counter reaches the BOTTOM
value.
In phase correct PWM mode, the compare unit allows generation of PWM waveforms on the
OC2x pin. Setting the COM2x1:0 bits to two will produce a non-inverted PWM. An inverted PWM
output can be generated by setting the COM2x1:0 to three. TOP is defined as 0xFF when
WGM2:0 = 3, and OCR2A when MGM2:0 = 7 (see
value will only be visible on the port pin if the data direction for the port pin is set as output. The
PWM waveform is generated by clearing (or setting) the OC2x Register at the compare match
between OCR2x and TCNT2 when the counter increments, and setting (or clearing) the OC2x
Register at compare match between OCR2x and TCNT2 when the counter decrements. The
PWM frequency for the output when using phase correct PWM can be calculated by the follow-
ing equation:
The N variable represents the prescale factor (1, 8, 32, 64, 128, 256, or 1024).
The extreme values for the OCR2A Register represent special cases when generating a PWM
waveform output in the phase correct PWM mode. If the OCR2A is set equal to BOTTOM, the
output will be continuously low and if set equal to MAX the output will be continuously high for
non-inverted PWM mode. For inverted PWM the output will have the opposite logic values.
At the very start of period 2 in
even though there is no Compare Match. The point of this transition is to guarantee symmetry
around BOTTOM. There are two cases that give a transition without Compare Match.
•
•
The 8-bit comparator continuously compares TCNT2 with the Output Compare Register
(OCR2A and OCR2B). Whenever TCNT2 equals OCR2A or OCR2B, the comparator signals a
match. A match will set the Output Compare Flag (OCF2A or OCF2B) at the next timer clock
cycle. If the corresponding interrupt is enabled, the Output Compare Flag generates an Output
Compare interrupt. The Output Compare Flag is automatically cleared when the interrupt is exe-
cuted. Alternatively, the Output Compare Flag can be cleared by software by writing a logical
one to its I/O bit location. The Waveform Generator uses the match signal to generate an output
according to operating mode set by the WGM22:0 bits and Compare Output mode (COM2x1:0)
bits. The max and bottom signals are used by the Waveform Generator for handling the special
cases of the extreme values in some modes of operation (see
176).
Figure 19-6 on page 181
OCR2A changes its value from MAX, like in
value is MAX the OCn pin value is the same as the result of a down-counting compare
match. To ensure symmetry around BOTTOM the OCn value at MAX must correspond to the
result of an up-counting Compare Match.
The timer starts counting from a value higher than the one in OCR2A, and for that reason
misses the Compare Match and hence the OCn change that would have happened on the
way up.
shows a block diagram of the Output Compare unit.
Figure 19-5 on page 179
ATmega640/1280/1281/2560/2561
f
OCnxPCPWM
Figure 19-5 on page
=
Table 19-4 on page
----------------- -
N 510
f
clk_I/O
⋅
OCnx has a transition from high to low
“Modes of Operation” on page
179. When the OCR2A
188). The actual OC2x
180
Related parts for ATMEGA2561-16AI
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
IC AVR MCU 2.4GHZ XCEIVER 64QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA644/AT86RF230 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA1281/AT86RF230 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA1280/AT86RF230 100TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA1280/AT86RF100-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA2560V/AT86RF230-ZU
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA2561/AT86RF230 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
INTERVAL AND WIPE/WASH WIPER CONTROL IC WITH DELAY
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
Low-Voltage Voice-Switched IC for Hands-Free Operation
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
MONOLITHIC INTEGRATED FEATUREPHONE CIRCUIT
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
AM-FM Receiver IC U4255BM-M
Manufacturer:
ATMEL Corporation
Datasheet: