Does CC2420 check the RSSI_VALID register before appending the RSSI value to the last two bytes of the packet?
Regards, Aleksandr. wbr, Sadkov Aleksandr [EMAIL PROTECTED] www.sumkino.com www.wl.unn.ru > -----Original Message----- > From: Tsung-Han Lin [mailto:[EMAIL PROTECTED] > Sent: Monday, June 18, 2007 3:07 PM > To: Aleksandr N. Sadkov > Cc: [email protected] > Subject: Re: [Tinyos-help] RSSI measuring > > RSSI value is measured by the radio chip. CC2420 will append the rssi, > crc and lqi to the last two bytes of the packet. > You can refer to the CC2420 datasheet: > http://www.chipcon.com/files/CC2420_Data_Sheet_1_3.pdf > > -Han > > Aleksandr N. Sadkov ??: > > Hello All, > > > > > > > > Could anybody explain how actually RSSI measured? > > > > > > > > I mean where source code in TinyOS for reading of the RSSI.RSSI_VAL > > register of the CC2420? > > > > > > > > I found only code: > > > > /task void receiveDone_task() {/ > > > > / / > > > > / cc2420_header_t* header = getHeader( m_p_rx_buf );/ > > > > / cc2420_metadata_t* metadata = getMetadata( m_p_rx_buf );/ > > > > / //uint8_t* buf = (uint8_t*)header;/ > > > > / //uint8_t length = buf[ 0 ];/ > > > > / / > > > > / metadata->crc = buf[ length ] >> 7;/ > > > > / metadata->rssi = buf[ length - 1 ];/ > > > > / metadata->lqi = buf[ length ] & 0x7f;/ > > > > / m_p_rx_buf = signal Receive.receive( m_p_rx_buf, m_p_rx_buf->data, > / > > > > / length );/ > > > > / / > > > > / waitForNextPacket();/ > > > > / / > > > > / }/ > > > > > > > > Could you explain why /buf[ length - 1 ]; /means RSSI/ ?/ > > > > / / > > > > Thank you, Aleksandr. > > > > > > > > > > > > wbr, Sadkov Aleksandr > > > > [EMAIL PROTECTED] > > > > www.sumkino.com <http://www.sumkino.com> > > > > www.wl.unn.ru > > > > > > > > > > ------------------------------------------------------------------------ > > > > _______________________________________________ > > Tinyos-help mailing list > > [email protected] > > https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos- > help _______________________________________________ Tinyos-help mailing list [email protected] https://mail.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
