sci_timer = timeout * 152;
while (sci_timer && sci_rx_buf_ptr_start == sci_rx_buf_ptr); /* spin */
if (sci_timer == 0) return SERIAL_TIMEOUT;
sci_timer = timeout * 152;
while (sci_timer && sci_rx_buf_ptr_start == sci_rx_buf_ptr); /* spin */
if (sci_timer == 0) return SERIAL_TIMEOUT;