AT90CAN128-16AI Atmel, AT90CAN128-16AI Datasheet - Page 183

• Manufacturer Part Number: AT90CAN128-16AI
• Description: IC MCU AVR FLASH 128K 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN128-16AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: CAN, EBI/EMI, I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 4K x 8
• Ram Size: 4K 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: 64-TQFP, 64-VQFP
• For Use With: ATDVK90CAN1 - KIT DEV FOR AT90CAN128 MCU
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

17.7
7679H–CAN–08/08
Data Transmission – USART Transmitter
check that there are no unread data in the receive buffer. Note that the TXCn flag must be
cleared before each transmission (before UDRn is written) if it is used for this purpose.
The following simple USART0 initialization code examples show one assembly and one C func-
tion that are equal in functionality. The examples assume asynchronous operation using polling
(no interrupts enabled) and a fixed frame format. The baud rate is given as a function parameter.
For the assembly code, the baud rate parameter is assumed to be stored in the r17:r16
Registers.
Note:
More advanced initialization routines can be made that include frame format as parameters, dis-
able interrupts and so on. However, many applications use a fixed setting of the baud and
control registers, and for these types of applications the initialization code can be placed directly
in the main routine, or be combined with initialization code for other I/O modules.
The USARTn Transmitter is enabled by setting the Transmit Enable (TXENn) bit in the UCSRnB
Register. When the Transmitter is enabled, the normal port operation of the TxDn pin is overrid-
den by the USARTn and given the function as the Transmitter’s serial output. The baud rate,
mode of operation and frame format must be set up once before doing any transmissions. If syn-
Assembly Code Example
C Code Example
USART0_Init:
void USART0_Init (unsigned int baud)
{
}
; Set baud rate
sts
sts
; Set frame format: 8data, no parity & 2 stop bits
ldi
sts
; Enable receiver and transmitter
ldi
sts
ret
/* Set baud rate */
UBRR0H = (unsigned char) (baud>>8);
UBRR0L = (unsigned char) baud;
/* Set frame format: 8data, no parity & 2 stop bits */
UCSR0C = (0<<UMSEL0) | (0<<UPM0) | (1<<USBS0) | (3<<UCSZ0);
/* Enable receiver and transmitter */
UCSR0B = (1<<RXEN0) | (1<<TXEN0);
1. The example code assumes that the part specific header file is included.
UBRR0H, r17
UBRR0L, r16
r16, (0<<UMSEL0)|(0<<UPM0)|(1<<USBS0)|(3<<UCSZ0)
UCSR0C, r16
r16, (1<<RXEN0)|(1<<TXEN0)
UCSR0B, r16
(1)
(1)
AT90CAN32/64/128
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