VERY_GOOD
rssi_qual = (rssi - 20) * (VERY_GOOD - GOOD) /
rssi_qual = (rssi - 30) * (PERFECT - VERY_GOOD) /
10 + VERY_GOOD;
tx_qual = (65 - tx_retries) * (VERY_GOOD - GOOD) /
(PERFECT - VERY_GOOD) / 50 + VERY_GOOD;
(VERY_GOOD - GOOD) / 20 + GOOD;
(PERFECT - VERY_GOOD) / 20 + VERY_GOOD;