contiki/core/dev/simple-cc2420.c
2007-04-03 19:05:44 +00:00

470 lines
13 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.
*
* @(#)$Id: simple-cc2420.c,v 1.5 2007/04/03 19:05:44 adamdunkels Exp $
*/
/*
* This code is almost device independent and should be easy to port.
*/
#include <stdio.h>
#include <string.h>
#include "contiki.h"
#if defined(__AVR__)
#include <avr/io.h>
#elif defined(__MSP430__)
#include <io.h>
#endif
/* #include "dev/leds.h" */
#include "dev/spi.h"
#include "dev/simple-cc2420.h"
#include "dev/cc2420_const.h"
#define FOOTER1_CRC_OK 0x80
#define FOOTER1_CORRELATION 0x7f
#if 0
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...) do {} while (0)
#endif
/*---------------------------------------------------------------------------*/
PROCESS(simple_cc2420_process, "CC2420 driver");
/*---------------------------------------------------------------------------*/
static void (* receiver_callback)(void);
signed char simple_cc2420_last_rssi;
u8_t simple_cc2420_last_correlation;
static u8_t receive_on;
/* Radio stuff in network byte order. */
static u16_t pan_id;
/*---------------------------------------------------------------------------*/
static unsigned
getreg(enum cc2420_register regname)
{
unsigned reg;
int s = splhigh();
FASTSPI_GETREG(regname, reg);
splx(s);
return reg;
}
/*---------------------------------------------------------------------------*/
static void
setreg(enum cc2420_register regname, unsigned value)
{
int s = splhigh();
FASTSPI_SETREG(regname, value);
splx(s);
}
/*---------------------------------------------------------------------------*/
static void
strobe(enum cc2420_register regname)
{
int s = splhigh();
FASTSPI_STROBE(regname);
splx(s);
}
/*---------------------------------------------------------------------------*/
static unsigned
status(void)
{
u8_t status;
int s = splhigh();
FASTSPI_UPD_STATUS(status);
splx(s);
return status;
}
/*---------------------------------------------------------------------------*/
#define AUTOACK (1 << 4)
#define ADR_DECODE (1 << 11)
#define RXFIFO_PROTECTION (1 << 9)
#define CORR_THR(n) (((n) & 0x1f) << 6)
#define FIFOP_THR(n) ((n) & 0x7f)
#define RXBPF_LOCUR (1 << 13);
/*---------------------------------------------------------------------------*/
void
simple_cc2420_set_receiver(void (* recv)(void))
{
receiver_callback = recv;
}
/*---------------------------------------------------------------------------*/
void
simple_cc2420_init(void)
{
u16_t reg;
{
int s = splhigh();
__cc2420_arch_init(); /* Initalize ports and SPI. */
DISABLE_FIFOP_INT();
FIFOP_INT_INIT();
splx(s);
}
/* Turn on voltage regulator and reset. */
SET_VREG_ACTIVE();
//clock_delay(250); OK
SET_RESET_ACTIVE();
clock_delay(127);
SET_RESET_INACTIVE();
//clock_delay(125); OK
/* Turn on the crystal oscillator. */
strobe(CC2420_SXOSCON);
/* Turn off automatic packet acknowledgment. */
reg = getreg(CC2420_MDMCTRL0);
reg &= ~AUTOACK;
setreg(CC2420_MDMCTRL0, reg);
/* Turn off address decoding. */
reg = getreg(CC2420_MDMCTRL0);
reg &= ~ADR_DECODE;
setreg(CC2420_MDMCTRL0, reg);
/* Change default values as recomended in the data sheet, */
/* correlation threshold = 20, RX bandpass filter = 1.3uA. */
setreg(CC2420_MDMCTRL1, CORR_THR(20));
reg = getreg(CC2420_RXCTRL1);
reg |= RXBPF_LOCUR;
setreg(CC2420_RXCTRL1, reg);
/* Set the FIFOP threshold to maximum. */
setreg(CC2420_IOCFG0, FIFOP_THR(127));
/* Turn off "Security enable" (page 32). */
reg = getreg(CC2420_SECCTRL0);
reg &= ~RXFIFO_PROTECTION;
setreg(CC2420_SECCTRL0, reg);
simple_cc2420_set_chan_pan_addr(11, 0xffff, 0x0000, NULL);
process_start(&simple_cc2420_process, NULL);
}
/*---------------------------------------------------------------------------*/
int
simple_cc2420_send(const u8_t *payload, u8_t payload_len)
{
u8_t spiStatusByte;
int s, i;
/* struct hdr_802_15::len shall *not* be counted, thus the -1.
* 2 == sizeof(footer).
*/
/* if(((hdr_len - 1) + payload_len + 2) > MAX_PACKET_LEN) {
return -1;
}*/
/* This code uses the CC2420 CCA (Clear Channel Assessment) to
* implement Carrier Sense Multiple Access with Collision Avoidance
* (CSMA-CA) and requires the receiver to be enabled and ready.
*/
if(!receive_on) {
return -2;
}
/* Wait for previous transmission to finish and RSSI. */
do {
spiStatusByte = status();
if(!(spiStatusByte & BV(CC2420_RSSI_VALID))) { /* RSSI needed by CCA */
continue;
}
} while(spiStatusByte & BV(CC2420_TX_ACTIVE));
#if 0
hdr->dst_pan = pan_id; /* Not at fixed position! xxx/bg */
last_correspondent = hdr->dst; /* Not dst either. */
last_used_seq++;
hdr->seq = last_used_seq;
cc2420_ack_received = 0;
#endif
/* Write packet to TX FIFO, appending FCS if AUTOCRC is enabled. */
strobe(CC2420_SFLUSHTX); /* Cancel send that never started. */
s = splhigh();
/* FASTSPI_WRITE_FIFO(hdr, hdr_len);*/
{
u8_t total_len = payload_len + 2; /* 2 bytes footer. */
FASTSPI_WRITE_FIFO(&total_len, 1);
}
FASTSPI_WRITE_FIFO(payload, payload_len);
splx(s);
PRINTF("simple_cc2420_send: wrote %d bytes\n", payload_len);
/* if(hdr->dst == 0xffff) {
int i;
for(i = 1; i < 3; i++) {
if(do_send() >= 0) {
return 0;
}
clock_delay(i*256);
}
}*/
if(FIFOP_IS_1 && !FIFO_IS_1) {
/* RXFIFO overflow, send on retransmit. */
PRINTF("rxfifo overflow!\n");
return -4;
}
/* The TX FIFO can only hold one packet! Make sure to not overrun
* FIFO by waiting for transmission to start here and synchronizing
* with the CC2420_TX_ACTIVE check in cc2420_send.
*
* Note that we may have to wait up to 320 us (20 symbols) before
* transmission starts.
*/
#ifdef TMOTE_SKY
#define LOOP_20_SYMBOLS 100 /* 326us (msp430 @ 2.4576MHz) */
#elif __AVR__
#define LOOP_20_SYMBOLS 500 /* XXX */
#endif
strobe(CC2420_STXONCCA);
for(i = LOOP_20_SYMBOLS; i > 0; i--) {
if(SFD_IS_1) {
PRINTF("simple_cc2420: do_send() transmission has started\n");
return 0; /* Transmission has started. */
}
}
PRINTF("simple_cc2420: do_send() transmission never started\n");
return -3; /* Transmission never started! */
}
/*---------------------------------------------------------------------------*/
void
simple_cc2420_off(void)
{
u8_t spiStatusByte;
if(receive_on == 0) {
return;
}
receive_on = 0;
/* Wait for transmission to end before turning radio off. */
do {
spiStatusByte = status();
} while(spiStatusByte & BV(CC2420_TX_ACTIVE));
strobe(CC2420_SRFOFF);
DISABLE_FIFOP_INT();
}
/*---------------------------------------------------------------------------*/
void
simple_cc2420_on(void)
{
if(receive_on) {
return;
}
receive_on = 1;
strobe(CC2420_SRXON);
strobe(CC2420_SFLUSHRX);
ENABLE_FIFOP_INT();
}
/*---------------------------------------------------------------------------*/
void
simple_cc2420_set_chan_pan_addr(unsigned channel, /* 11 - 26 */
unsigned pan,
unsigned addr,
const u8_t *ieee_addr)
{
/*
* Subtract the base channel (11), multiply by 5, which is the
* channel spacing. 357 is 2405-2048 and 0x4000 is LOCK_THR = 1.
*/
u8_t spiStatusByte;
u16_t f = channel;
int s;
f = 5*(f - 11) + 357 + 0x4000;
/*
* Writing RAM requires crystal oscillator to be stable.
*/
do {
spiStatusByte = status();
} while(!(spiStatusByte & (BV(CC2420_XOSC16M_STABLE))));
pan_id = pan;
setreg(CC2420_FSCTRL, f);
s = splhigh();
FASTSPI_WRITE_RAM_LE(&pan, CC2420RAM_PANID, 2, f);
FASTSPI_WRITE_RAM_LE(&addr, CC2420RAM_SHORTADDR, 2, f);
if(ieee_addr != NULL) {
FASTSPI_WRITE_RAM_LE(ieee_addr, CC2420RAM_IEEEADDR, 8, f);
}
splx(s);
}
/*---------------------------------------------------------------------------*/
static volatile u8_t rx_fifo_remaining_bytes;
/*---------------------------------------------------------------------------*/
void
radio_on(void)
{
simple_cc2420_on();
}
/*---------------------------------------------------------------------------*/
void
radio_off(void)
{
/* Turn the receiver off, but only if we have not recently received
a packet. */
if(rx_fifo_remaining_bytes == 0) {
simple_cc2420_off();
}
}
/*---------------------------------------------------------------------------*/
/*
* Interrupt either leaves frame intact in FIFO or reads *only* the
* MAC header and sets rx_fifo_remaining_bytes.
*
* In order to quickly empty the FIFO ack processing is done at
* interrupt priority rather than poll priority.
*/
int
__cc2420_intr(void)
{
u8_t length;
/* const u8_t *const ack_footer = (u8_t *)&h.dst_pan;*/
CLEAR_FIFOP_INT();
if(spi_busy || rx_fifo_remaining_bytes > 0) {
/* SPI bus hardware is currently used elsewhere (UART0 or I2C bus)
* or we already have a packet in the works and will have to defer
* interrupt processing of this packet in a fake interrupt.
*/
process_poll(&simple_cc2420_process);
return 1;
}
FASTSPI_READ_FIFO_BYTE(length);
if(length > SIMPLE_CC2420_MAX_PACKET_LEN) {
/* Oops, we must be out of sync. */
FASTSPI_STROBE(CC2420_SFLUSHRX);
FASTSPI_STROBE(CC2420_SFLUSHRX);
return 0;
}
/* The payload and footer is now left in the RX FIFO and will be
* picked up asynchronously at poll priority in the cc2420_process
* below.
*/
rx_fifo_remaining_bytes = length;
process_poll(&simple_cc2420_process);
return 1;
}
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(simple_cc2420_process, ev, data)
{
PROCESS_BEGIN();
while(1) {
PROCESS_YIELD();
if(receiver_callback != NULL) {
receiver_callback();
} else {
PRINTF("simple_cc2420_process dropping %d bytes\n",
rx_fifo_remaining_bytes);
if(rx_fifo_remaining_bytes > 0) {
int s;
s = splhigh();
FASTSPI_READ_FIFO_GARBAGE(rx_fifo_remaining_bytes);
rx_fifo_remaining_bytes = 0; /* RX FIFO emptied! */
splx(s);
}
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/
int
simple_cc2420_read(u8_t *buf, u8_t bufsize)
{
u8_t footer[2];
int len;
int s;
len = rx_fifo_remaining_bytes;
if(len > 0) {
/* Read payload and two bytes of footer */
if(len > bufsize) {
PRINTF("simple_cc2420_poll too big len=%d\n", len);
s = splhigh();
FASTSPI_READ_FIFO_GARBAGE(len);
rx_fifo_remaining_bytes = 0; /* RX FIFO emptied! */
splx(s);
len = 2; /* We eventually return len - 2 */
} else {
s = splhigh();
FASTSPI_READ_FIFO_NO_WAIT(buf, len - 2);
FASTSPI_READ_FIFO_NO_WAIT(footer, 2);
rx_fifo_remaining_bytes = 0; /* RX FIFO emptied! */
splx(s);
if(footer[1] & FOOTER1_CRC_OK) {
simple_cc2420_last_rssi = footer[0];
simple_cc2420_last_correlation = footer[1] & FOOTER1_CORRELATION;
/* if((h.fc0 & FC0_TYPE_MASK) == FC0_TYPE_DATA) {
uip_len = len - 2;
}*/
}
}
}
/* Clean up in case of FIFO overflow! This happens for every full
* length frame and is signaled by FIFOP = 1 and FIFO = 0.
*/
if(FIFOP_IS_1 && !FIFO_IS_1) {
strobe(CC2420_SFLUSHRX);
strobe(CC2420_SFLUSHRX);
}
if(FIFOP_IS_1) {
s = splhigh();
__cc2420_intr(); /* Fake interrupt! */
splx(s);
}
return len - 2; /* Remove two bytes for the footer. */
}
/*---------------------------------------------------------------------------*/