osd-contiki/examples/rssi-scanner/rssi-scanner-cc2420.c

103 lines
3.3 KiB
C

/*
* Copyright (c) 2007, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* Scanning 2.4 GHz radio frequencies using CC2420 and prints
* the values
* \author
* Joakim Eriksson, joakime@sics.se
*/
#include "contiki.h"
#include "net/rime/rime.h"
#include "net/netstack.h"
#include "dev/leds.h"
#include "cc2420.h"
#include "cc2420_const.h"
#include "dev/spi.h"
#include <stdio.h>
/*---------------------------------------------------------------------------*/
/* This assumes that the CC2420 is always on and "stable" */
static void
set_frq(int c)
{
int f;
/* We can read even other channels with CC2420! */
/* Fc = 2048 + FSCTRL ; Fc = 2405 + 5(k-11) MHz, k=11,12, ... , 26 */
f = c + 352; /* Start from 2400 MHz to 2485 MHz, */
/* Write the new channel value */
CC2420_SPI_ENABLE();
SPI_WRITE_FAST(CC2420_FSCTRL);
SPI_WRITE_FAST((uint8_t)(f >> 8));
SPI_WRITE_FAST((uint8_t)(f & 0xff));
SPI_WAITFORTx_ENDED();
SPI_WRITE(0);
/* Send the strobe */
SPI_WRITE(CC2420_SRXON);
CC2420_SPI_DISABLE();
}
static void
do_rssi(void)
{
int channel;
printf("RSSI:");
for(channel = 0; channel <= 85; ++channel) {
set_frq(channel);
printf("%d ", cc2420_rssi() + 100);
}
printf("\n");
}
/*---------------------------------------------------------------------------*/
PROCESS(scanner_process, "RSSI Scanner");
AUTOSTART_PROCESSES(&scanner_process);
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(scanner_process, ev, data)
{
PROCESS_BEGIN();
/* switch mac layer off, and turn radio on */
NETSTACK_MAC.off(0);
cc2420_on();
while(1) {
do_rssi();
PROCESS_PAUSE();
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/