ATmega329P Atmel Corporation, ATmega329P Datasheet - Page 181

• Manufacturer Part Number: ATmega329P
• Manufacturer: Atmel Corporation

Specifications of ATmega329P

• Flash (kbytes): 32 Kbytes
• Pin Count: 64
• Max. Operating Frequency: 20 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 16
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 54
• Ext Interrupts: 17
• Usb Speed: No
• Usb Interface: No
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Segment Lcd: 100
• 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): 2
• Eeprom (bytes): 1024
• 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: 4
• Input Capture Channels: 1
• Pwm Channels: 4
• 32khz Rtc: Yes
• Calibrated Rc Oscillator: Yes

19.7.2
8021G–AVR–03/11
Receiving Frames with 9 Data Bits
bits of the data read from the UDRn will be masked to zero. The USART has to be initialized
before the function can be used.
Note:
The function simply waits for data to be present in the receive buffer by checking the RXCn Flag,
before reading the buffer and returning the value.
If 9-bit characters are used (UCSZ=7), the ninth bit must be read from the RXB8n bit in UCSRnB
before reading the low bits from the UDRn. This rule applies to the FEn, DORn and UPEn Status
Flags as well. Read status from UCSRnA, then data from UDRn. Reading the UDRn I/O location
will change the state of the receive buffer FIFO and consequently the TXB8n, FEn, DORn and
UPEn bits, which all are stored in the FIFO, will change.
Assembly Code Example
C Code Example
USART_Receive:
unsigned char USART_Receive( void )
{
}
; Wait for data to be received
sbis UCSR0A, RXC0
rjmp USART_Receive
; Get and return received data from buffer
in
ret
/* Wait for data to be received */
while ( !(UCSR0A & (1<<RXC0)) )
/* Get and return received data from buffer */
return UDR0;
1.
See Section “5.” on page 9.
r16, UDR0
;
(1)
(1)
ATmega329P/3290P
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