/* Processes data packets received from the Gumstix
*/
void process_data_packet( void )
{
uint8_t packet[ COMM_BUF_SIZE ], size;
uint16_t checksum;
/* get data from serial or parallel interface */
if( serial_get_data( packet ) )//&& parallel_get_data( packet ) )
{
return;
}
/* check for valid packet content */
size = packet[1] + COMM_OVERHEAD - 2;
checksum = (packet[ size-2 ] << 8) | packet[ size-1 ];
size -= 2;
/* iterate over payload */
while( size-- )
{
checksum -= packet[ size ];
}
/* check for non-zero checksum */
if( checksum )
{
return;
}
/* call packet-dependent function */
switch( packet[0] )
{
case COMM_SENSOR_DATA:
process_sensor_data( packet + 2, packet[1] );
break;
case COMM_MOTOR_SIGNALS:
process_motor_signals( packet + 2, packet[1] );
break;
case COMM_SWITCH_STATE:
process_state_switch( );
break;
case COMM_SHUT_DOWN:
process_shut_down( );
break;
default:
return;
}
}
int main(int argc, char * argv[])
{
if (argc < 2) {
fprintf(stderr, "Usage: %s device\n", argv[0]);
exit(1);
}
int fd = serial_init(argv[1]);
if (fd == -1) {
exit(1);
}
unsigned int data[8];
for (;;) {
if (serial_get_data(fd, data)) {
printf("%5u %5u %5u %5u %5u %5u %5u %5u\n",
data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]);
}
}
serial_stop(fd);
return 0;
}
