void immob_check_state(struct ecudata_t* d)
{
uint8_t i = 0, crc = 0;
uint8_t key[8];
if (!(d->param.bt_flags & _BV(BTF_USE_IMM)))
return; //immibilizer was not activated
onewire_save_io_registers();
if (!onewire_reset())
goto lock_system; //not device present, lock the system!
//Read 64-bit key
onewire_write_byte(OWCMD_READ_ROM);
for(; i < 8; ++i) key[i] = onewire_read_byte();
//validate CRC8, all bytes except CRC8 byte
for(i = 0; i < 7; ++i) crc = update_crc8(key[i], crc);
if (crc != key[7])
goto lock_system; //crc doesn't match, lock the system!
//validate read key, skip family code and CRC8 bytes
if (!validate_key(d, key+1, IBTN_KEY_SIZE))
goto lock_system; //read and stored keys don't match, lock the system!
onewire_restore_io_registers();
return; //ok, system is unlocked
lock_system:
onewire_restore_io_registers();
d->sys_locked = 1; //set locking flag
}
uint8_t calculate_crc8(uint8_t *p, unsigned int length) {
uint8_t crc;
unsigned int i;
crc = 0;
for (i=0; i < length; i++) {
crc = update_crc8(crc,*p++);
}
return crc;
}
void __attribute__((__interrupt__, no_auto_psv)) _U2RXInterrupt(void) {
unsigned char c;
while(U2STAbits.URXDA) {
c = U2RXREG;
// If we just received the second character, set packet length
if (in_pkt_idx_ == 1) {
in_pkt_len_ = c;
}
// If there has been a parse error, reset packet buffer
if ((in_pkt_idx_ == 0 && c != PKT_START_CHAR) || in_pkt_len_ < sizeof(header_t)+1 ) {
in_pkt_idx_ = 0;
in_pkt_len_ = MAX_PACKET_LENGTH;
in_pkt_crc_ = 0;
// Store byte in packet buffer and update CRC
} else {
in_pkt_->raw[in_pkt_idx_++] = c;
in_pkt_crc_ = update_crc8(in_pkt_crc_, c);
}
// If we just received the last character and CRC is good,
// swap with last_packet and reset packet buffer
if (in_pkt_idx_ == in_pkt_len_) {
if (in_pkt_crc_ == 0) {
last_bldc_packet_is_new = 1;
LED_2 ^= 1;
LED_3 = 1;
if(last_bldc_packet == &(pkt_buf_0_)) {
last_bldc_packet = &(pkt_buf_1_);
in_pkt_ = &(pkt_buf_0_);
} else {
last_bldc_packet = &(pkt_buf_0_);
in_pkt_ = &(pkt_buf_1_);
}
}
in_pkt_idx_ = 0;
in_pkt_len_ = MAX_PACKET_LENGTH;
in_pkt_crc_ = 0;
}
}
if(U2STAbits.OERR) {
U2STAbits.OERR = 0;
}
_U2RXIF = 0;
}
static uint8_t get_crc8(uint8_t *Buf, uint8_t BufLen)
{
uint8_t crc = 0;
for(int i=0; i<BufLen; i++) crc = update_crc8(Buf[i], crc);
return (crc);
}
