Honda door unlock rolling code

// function that will generate the unlock rolling code for Honda
// input:  code - The code that you need to send to car.
//         send_data = The data to be sent to the car's immobilizer.
// output: The rolling code checksum.
uint8_t unlock_rolling_code (uint8_t code, uint8_t *send_data)
{
  uint8_t rolling_code;
  
  rolling_code = code;
  send_data[2] = code;
  send_data[3] = rolling_code;
  rolling_code = ((rolling_code << 1) | (rolling_code >> 7)) ^ code;
  send_data[4] = rolling_code;
  rolling_code = ((rolling_code << 1) | (rolling_code >> 7)) ^ code;
  send_data[5] = rolling_code;
  rolling_code = ((rolling_code << 1) | (rolling_code >> 7)) ^ code;
  send_data[6] = rolling_code;
  
  return rolling_code