[Tinyos-help] Varying transmitter power level

[sstl vls]

Hello all,

Iam trying to estimate the minimum required power level of a mote, based on the actual transmission power level of packets from neighbhors and received strength (RSSI) of the packets. Iam using TmoteSky nodes. I used the uint8_t getPower( message_t* p_msg ) command provided by CC2420Packet interface to estimate the transmitted power level and  int8_t getRssi( message_t* p_msg ) comand to get the RSSI values. 

From CC2420 Chipcon data sheets, I learnt that the PA_LEVEL (getPower) can be any of 3, 7, 11, 15, 19, 23, 27, 31 (CC2420Packet interface says it can be between 0 and 32.) I assume they are Hexadecimal values..
 
The problem is when I tested it on actual motes, I get a range of values for   getPower  : 00 or 1f to 23 or d0 to df

The values d0 to df are incorrect (and I get them very often ).  Can someone please tell me why this is happening. Is something wrong?

Did someone implement this already?

- Sreevalli







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