// ----------------------------------------------------------------------------
void sja1000_set_mode(can_mode_t mode)
{
uint8_t reg = 0;
// enter reset mode
sja1000_write(MOD, (1<<AFM) | (1<<RM));
if (mode == LISTEN_ONLY_MODE) {
reg = (1<<LOM);
}
else if (mode == LOOPBACK_MODE) {
reg = (1<<STM);
}
// set new mode
sja1000_write(MOD, (1<<AFM) | (1<<RM) | reg);
// leave reset mode
sja1000_write(MOD, (1<<AFM) | reg);
}
uint8_t sja1000_send_message(const can_t *msg)
{
uint8_t frame_info;
uint8_t address;
if (!sja1000_check_free_buffer() || (msg->length > 8))
return FALSE;
frame_info = msg->length | ((msg->flags.rtr) ? (1<<RTR) : 0);
if (msg->flags.extended)
{
// write frame info
sja1000_write(TX_INFO, frame_info | (1<<FF));
// write extended identifier
sja1000_write(20, msg->id << 3);
sja1000_write(19, msg->id >> 5);
sja1000_write(18, msg->id >> 13);
sja1000_write(17, msg->id >> 21);
address = 21;
}
bool sja1000_init(uint8_t bitrate)
{
if (bitrate >= 8)
return false;
#if !SJA1000_MEMORY_MAPPED
SET(SJA1000_WR);
SET(SJA1000_RD);
RESET(SJA1000_ALE);
RESET(SJA1000_CS);
SET_OUTPUT(SJA1000_WR);
SET_OUTPUT(SJA1000_RD);
SET_OUTPUT(SJA1000_ALE);
SET_OUTPUT(SJA1000_CS);
DDR(SJA1000_DATA) = 0xff;
#endif
// enter reset mode
sja1000_write(MOD, (1<<RM)|(1<<AFM));
// choose PeliCAN-Mode
sja1000_write(CDR, (1<<CANMODE) | SJA1000_CLOCK_REGISTER);
// select the bitrate configuration
sja1000_write(BTR0, pgm_read_byte(&_sja1000_cnf[bitrate][0]));
sja1000_write(BTR1, pgm_read_byte(&_sja1000_cnf[bitrate][1]));
// filter are not practical useable, so we disable them
sja1000_write(AMR0, 0xff);
sja1000_write(AMR1, 0xff);
sja1000_write(AMR2, 0xff);
sja1000_write(AMR3, 0xff);
// set output driver configuration
sja1000_write(OCR, (1<<OCTP0)|(1<<OCTN0)|(1<<OCMODE1));
// enable receive interrupt
sja1000_write(IER, (1<<RIE));
// leave reset-mode
sja1000_write(MOD, (1<<AFM));
return true;
}
// ----------------------------------------------------------------------------
void sja1000_reset_bus_off(void)
{
uint8_t status = sja1000_read(SR) & (1<<BS);
sja1000_write(SR, status & ~(1<<BS));
}