ATmega644P Atmel Corporation, ATmega644P Datasheet - Page 434

• Manufacturer Part Number: ATmega644P
• Manufacturer: Atmel Corporation

Specifications of ATmega644P

• Flash (kbytes): 64 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 32
• Ext Interrupts: 32
• Usb Speed: No
• Usb Interface: No
• Spi: 3
• Twi (i2c): 1
• Uart: 2
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 8
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: No
• Crypto Engine: No
• Sram (kbytes): 4
• Eeprom (bytes): 2048
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: Yes
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 1.8 to 5.5
• Operating Voltage (vcc): 1.8 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 3
• Output Compare Channels: 6
• Input Capture Channels: 1
• Pwm Channels: 6
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

8011O–AVR–07/10
15 SPI – Serial Peripheral Interface ......................................................... 161
16 USART ................................................................................................... 171
17 USART in SPI Mode ............................................................................. 198
14.5 Output Compare Unit .........................................................................................141
14.6 Compare Match Output Unit ...............................................................................143
14.7 Modes of Operation ............................................................................................144
14.8 Timer/Counter Timing Diagrams ........................................................................148
14.9 Asynchronous Operation of Timer/Counter2 ......................................................150
14.10 Timer/Counter Prescaler ..................................................................................152
14.11 Register Description .........................................................................................152
15.1 Features .............................................................................................................161
15.2 Overview ............................................................................................................161
15.3 SS Pin Functionality ...........................................................................................166
15.4 Data Modes ........................................................................................................166
15.5 Register Description ...........................................................................................168
16.1 Features .............................................................................................................171
16.2 USART1 and USART0 .......................................................................................171
16.3 Overview ............................................................................................................171
16.4 Clock Generation ................................................................................................172
16.5 Frame Formats ...................................................................................................175
16.6 USART Initialization ...........................................................................................176
16.7 Data Transmission – The USART Transmitter ...................................................177
16.8 Data Reception – The USART Receiver ............................................................180
16.9 Asynchronous Data Reception ...........................................................................184
16.10 Multi-processor Communication Mode .............................................................187
16.11 Register Description .........................................................................................189
16.12 Examples of Baud Rate Setting .......................................................................194
17.1 Features .............................................................................................................198
17.2 Overview ............................................................................................................198
17.3 Clock Generation ................................................................................................198
17.4 SPI Data Modes and Timing ..............................................................................199
17.5 Frame Formats ...................................................................................................199
17.6 Data Transfer .....................................................................................................201
17.7 AVR USART MSPIM vs. AVR SPI .....................................................................203
17.8 Register Description ...........................................................................................204
ATmega164P/324P/644P
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