ATMEGA32A-AN Atmel, ATMEGA32A-AN Datasheet - Page 158

• Manufacturer Part Number: ATMEGA32A-AN
• Description: IC MCU AVR 32K FLASH 44TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32A-AN

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

19.7.2
8155C–AVR–02/11
Receiving Frames with 9 Databits
bits of the data read from the UDR 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 RXC 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 RXB8 bit in UCSRB
before reading the low bits from the UDR. This rule applies to the FE, DOR and PE Status Flags
as well. Read status from UCSRA, then data from UDR. Reading the UDR I/O location will
change the state of the receive buffer FIFO and consequently the TXB8, FE, DOR and PE bits,
which all are stored in the FIFO, will change.
The following code example shows a simple USART receive function that handles both 9-bit
characters and the status bits.
Assembly Code Example
C Code Example
USART_Receive:
unsigned char USART_Receive( void )
{
}
; Wait for data to be received
sbis UCSRA, RXC
rjmp USART_Receive
; Get and return received data from buffer
in
ret
/* Wait for data to be received */
while ( !(UCSRA & (1<<RXC)) )
/* Get and return received data from buffer */
return UDR;
1. See
r16, UDR
;
“About Code Examples” on page
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6.
ATmega32A
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