You may have to take this application as an example and convert it to provide the information you're looking for. This app's original intention was to give you a warm fuzzy feeling about RSSI coming out of the CC2420.
Page 49 of the CC2420 data sheet offers more information about RSSI and what it means: The RSSI register value RSSI.RSSI_VAL can be referred to the power P at the RF pins by using the following equations: P = RSSI_VAL + RSSI_OFFSET [dBm] where the RSSI_OFFSET is found empirically during system development from the front end gain. RSSI_OFFSET is approximately -45. E.g. if reading a value of -20 from the RSSI register, the RF input power is approximately -65 dBm. On the embedded side of this application, we're simply streaming raw RSSI values from the radio and sending them in a packet through the serial port. The Java side accepts those packets, does some GUI-friendly mangling to the RSSI value, and displays the bar graph. If you're going to start anywhere, I'd recommend editing the Java application to print out the raw RSSI values to the screen perhaps, or using the equation from the datasheet to convert them to [dBm]. It's a pretty easy hack. -David _____ From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of sergio mena doce Sent: Tuesday, October 30, 2007 3:24 AM To: tinyos-help@millennium.berkeley.edu Subject: [Tinyos-help] Question abouttinyos-2.x/apps/tests/cc2420/RssiToSerial Hello. I'm a telecommunications engineering degree student from Barcelona (Spain). I'm working with tinyos-2.x under Linux. I have a question executing the RssiToSerial application. As you would can know, RssiToSerial shows by console strings like the following: [+++++++++++++++++++++++++++++++++++ ] When there isn't transmitter activity it shows: [+++++++++++++++ ] In the file README.txt of the RssiToSerial tells that since the Java side has to convert the readings into a CLI bar graph, it's scaled by some (possibly non-linear) factor. Is there any way to read the Rssi in dBm's, dBW,s or some units to measure the power of the Rssi? What does mean each '+' additive char of the string? Thanks by your help. _____ Express yourself instantly with MSN Messenger! MSN <http://clk.atdmt.com/AVE/go/onm00200471ave/direct/01/> Messenger
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