ATMEGA162L-8MI Atmel, ATMEGA162L-8MI Datasheet - Page 174

• Manufacturer Part Number: ATMEGA162L-8MI
• Description: IC MCU AVR 16K 3V 8MHZ 44-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA162L-8MI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: EBI/EMI, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 35
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 512 x 8
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN Exposed Pad
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Data Converters: -

Receiving Frames with 9 Data
Bits
174
ATmega162(V/U/L)
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
UPE 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 UPE bits, which all are stored in the FIFO, will change.
The following code example shows a simple USART receive function that handles both
nine bit characters and the status bits.
Note:
Assembly Code Example
C Code Example
USART_Receive:
USART_ReceiveNoError:
unsigned int USART_Receive( void )
{
}
; Wait for data to be received
sbis UCSRA, RXC
rjmp USART_Receive
; Get status and 9th bit, then data from buffer
in
in
in
; If error, return -1
andi r18,(1<<FE)|(1<<DOR)|(1<<UPE)
breq USART_ReceiveNoError
ldi
ldi
; Filter the 9th bit, then return
lsr
andi r17, 0x01
ret
unsigned char status, resh, resl;
/* Wait for data to be received */
while ( !(UCSRA & (1<<RXC)) )
/* Get status and 9th bit, then data */
/* from buffer */
status = UCSRA;
resh = UCSRB;
resl = UDR;
/* If error, return -1 */
if ( status & (1<<FE)|(1<<DOR)|(1<<UPE) )
/* Filter the 9th bit, then return */
resh = (resh >> 1) & 0x01;
return ((resh << 8) | resl);
1. The example code assumes that the part specific header file is included.
return -1;
r18, UCSRA
r17, UCSRB
r16, UDR
r17, HIGH(-1)
r16, LOW(-1)
r17
;
(1)
(1)
2513C–AVR–09/02