AT90CAN64-16AUR Atmel, AT90CAN64-16AUR Datasheet - Page 185

• Manufacturer Part Number: AT90CAN64-16AUR
• Description: MCU AVR 64K FLASH 16MHZ 64TQFP
• Manufacturer: Atmel
• Series: AVR® 90CANr

Specifications of AT90CAN64-16AUR

• 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: 64KB (64K x 8)
• Program Memory Type: FLASH
• Eeprom Size: 2K 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
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

17.7.2
17.7.3
7679H–CAN–08/08
Sending Frames with 9 Data Bit
Transmitter Flags and Interrupts
If 9-bit characters are used (UCSZn = 7), the ninth bit must be written to the TXB8n bit in UCS-
RnB before the low byte of the character is written to UDRn. The following code examples show
a transmit function that handles 9-bit characters. For the assembly code, the data to be sent is
assumed to be stored in registers R17:R16.
Notes:
The ninth bit can be used for indicating an address frame when using multi processor communi-
cation mode or for other protocol handling as for example synchronization.
The USARTn Transmitter has two flags that indicate its state: USART Data Register Empty
(UDREn) and Transmit Complete (TXCn). Both flags can be used for generating interrupts.
Assembly Code Example
C Code Example
USART0_Transmit:
void USART0_Transmit (unsigned int data)
{
}
; Wait for empty transmit buffer
lds
sbrs
rjmp
; Copy 9th bit from r17-bit0 to TXB80 via T-bit of SREG
lds
bst
bld
sts
; Put LSB data (r16) into buffer, sends the data
sts
ret
/* Wait for empty transmit buffer */
while ( !( UCSR0A & (1<<UDRE0)));
/* Copy 9th bit to TXB8 */
UCSR0B &= ~(1<<TXB80);
if ( data & 0x0100 )
/* Put data into buffer, sends the data */
UDR0 = data;
1. These transmit functions are written to be general functions. They can be optimized if the con-
2. The example code assumes that the part specific header file is included.
UCSR0B |= (1<<TXB80);
tents of the UCSR0B is static. For example, only the TXB80 bit of the UCSRB0 Register is
used after initialization.
r18, UCSR0A
r18, UDRE0
USART0_Transmit
r18, UCSR0B
r17, 0
r18, TXB80
UCSR0B, r18
UDR0, r16
(1)(2)
(1)(2)
AT90CAN32/64/128
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