avr can芯片使用

struct MOb
{
unsigned long id;
unsigned char data [8];
};
void can_init (void);
void can_tx (struct MOb msg);
void can_rx (struct MOb msg);
 
void can_init (void)
{
unsigned char i,j;
//reset CAN interface
CANGCON |= (1< baudrate
// bit timing -> datasheet 264 (check table)
// 250Kbps 16MHz cpu-clk
CANBT1 = 0x0E;//16M/8=2M
CANBT2 = 0x04;//3QT
CANBT3 = 0x13;//2+2=4
// clear CAN interrupt registers
CANGIE = 0; // none interrupts
CANIE1 = 0; // none interrupts on MObs
CANIE2 = 0;
CANSIT1 = 0;
CANSIT2 = 0;
//start CAN interface
CANGCON = (1<<1);
//wait until module ready
while (!(CANGSTA & (1<>8);
CANIDT2 = (unsigned char) (msg.id>>16);
CANIDT1 = (unsigned char) (msg.id>>24);
//put data in mailbox
for (i=0; i<8; i++)
CANMSG = msg.data [i];
//enable transmission
CANCDMOB |= (1<> 5);
CANIDT2 = (unsigned char)(msg.id >> 13);
CANIDT1 = (unsigned char)(msg.id >> 21);
// set mask in order to receive only the message with the ID
CANIDM4 = 248;
CANIDM3 = 255;
CANIDM2 = 255;
CANIDM1 = 255;
// enable extended ID
CANIDM4 |= (1<>= 3;
}