I am currently using a board with a AT86RF215 transceiver. I am trying to change the transmit power of the transceiver. According to the datasheet, the possible transmit power for the 2.4 GHz band appears to be between 11 dBm and 15.5 dBm [1, p. 191].
When I tried to set the transmit power to 15.5, the following happened:
2019-02-16 07:14:31,297 - INFO # > ifconfig 7 set power 15.5 2019-02-16 07:14:31,304 - INFO # success: set TX power [in dBm] on interface 7 to 15 ifconfig 2019-02-16 07:14:33,064 - INFO # > ifconfig 2019-02-16 07:14:33,073 - INFO # Iface 7 HWaddr: 01:66 Channel: 26 Page: 0 NID: 0x23 PHY: O-QPSK 2019-02-16 07:14:33,075 - INFO # 2019-02-16 07:14:33,080 - INFO # Long HWaddr: 4E:49:6F:54:4F:76:01:66 2019-02-16 07:14:33,088 - INFO # TX-Power: 3dBm State: IDLE max. Retrans.: 3 CSMA Retries: 4
A transmit power of 3 dBm is printed. It appears that the power can be set either to 0 (default), 1, 2 or 3 dBm. Now I am a little bit confused, because I don’t understand how this is related to the transmit power range listed in the datasheet. Maybe I am reading the datasheet totally wrong. Could someone help me understand this? Thank you!