mirror of
git://projects.qi-hardware.com/antorcha.git
synced 2024-12-23 18:52:59 +02:00
146 lines
2.8 KiB
C
146 lines
2.8 KiB
C
/*
|
|
* fw/rf.c - RF interface
|
|
*
|
|
* Written 2012 by Werner Almesberger
|
|
* Copyright 2012 Werner Almesberger
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
|
|
#include <stdint.h>
|
|
|
|
#include <avr/io.h>
|
|
#define F_CPU 8000000UL
|
|
#include <util/delay.h>
|
|
|
|
#include <at86rf230.h>
|
|
|
|
#include "io.h"
|
|
#include "spi.h"
|
|
#include "rf.h"
|
|
|
|
|
|
/*
|
|
* According to IEEE 802.15.4-2003 section E.2.6, channel 15 is the only
|
|
* channel that falls into the 802.11 guard bands in North America an Europe.
|
|
*/
|
|
|
|
#define DEFAULT_CHAN 15 /* channel 15, 2425 MHz */
|
|
|
|
/*
|
|
* Transmit power, dBm. IEEE 802.15.4-2003 section E.3.1.3 specifies a transmit
|
|
* power of 0 dBm for IEEE 802.15.4. We assume an antenna gain of 3 dB or
|
|
* better.
|
|
*/
|
|
|
|
#define DEFAULT_POWER -3.2 /* transmit power, dBm */
|
|
|
|
|
|
static uint8_t reg_read(uint8_t reg)
|
|
{
|
|
uint8_t value;
|
|
|
|
spi_begin();
|
|
spi_send(AT86RF230_REG_READ | reg);
|
|
value = spi_recv();
|
|
spi_end();
|
|
|
|
return value;
|
|
}
|
|
|
|
|
|
static void reg_write(uint8_t reg, uint8_t value)
|
|
{
|
|
spi_begin();
|
|
spi_send(AT86RF230_REG_WRITE | reg);
|
|
spi_send(value);
|
|
spi_end();
|
|
}
|
|
|
|
|
|
void rf_init(void)
|
|
{
|
|
spi_init();
|
|
CLR(RF_nRST);
|
|
_delay_us(10); /* tTR10 = 625 ns */
|
|
SET(RF_nRST);
|
|
_delay_us(40); /* tTR13 = 37 us */
|
|
|
|
reg_write(REG_TRX_STATE, TRX_CMD_TRX_OFF);
|
|
_delay_us(40); /* tTR13 = 37 us */
|
|
reg_write(REG_PHY_CC_CCA, DEFAULT_CHAN);
|
|
|
|
reg_write(REG_TRX_STATE, TRX_CMD_RX_ON);
|
|
_delay_us(200); /* tTR19(max) = 166 us */
|
|
|
|
//reg_write(REG_IRQ_MASK, IRQ_TRX_END);
|
|
reg_write(REG_IRQ_MASK, 0xff);
|
|
reg_read(REG_IRQ_STATUS);
|
|
}
|
|
|
|
|
|
void rf_send(const void *buf, uint8_t size)
|
|
{
|
|
uint8_t i;
|
|
|
|
reg_write(REG_TRX_STATE, TRX_CMD_PLL_ON);
|
|
_delay_us(1); /* tTR9 = 1 us */
|
|
|
|
/* be nice to senders with long turn-around time, e.g., atusb */
|
|
_delay_ms(2);
|
|
|
|
spi_begin();
|
|
spi_send(AT86RF230_BUF_WRITE);
|
|
spi_send(size+2); /* CRC */
|
|
for (i = 0; i != size; i++)
|
|
spi_send(((const uint8_t *) buf)[i]);
|
|
spi_end();
|
|
|
|
reg_read(REG_IRQ_STATUS);
|
|
|
|
reg_write(REG_TRX_STATE, TRX_CMD_TX_START);
|
|
_delay_us(16); /* tTR10 = 16 us */
|
|
|
|
while (!(reg_read(REG_IRQ_STATUS) & IRQ_TRX_END)) {
|
|
PORTC = 1;
|
|
PORTC = 0;
|
|
}
|
|
|
|
reg_write(REG_TRX_STATE, TRX_CMD_RX_ON);
|
|
_delay_us(1); /* tTR8 = 1 us */
|
|
}
|
|
|
|
|
|
uint8_t rf_recv(void *buf, uint8_t size)
|
|
{
|
|
uint8_t irq, len, i;
|
|
|
|
if (!PIN(RF_IRQ))
|
|
return 0;
|
|
|
|
irq = reg_read(REG_IRQ_STATUS);
|
|
if (!(irq & IRQ_TRX_END))
|
|
return 0;
|
|
|
|
if (!(reg_read(REG_PHY_RSSI) & RX_CRC_VALID))
|
|
return 0;
|
|
|
|
spi_begin();
|
|
spi_send(AT86RF230_BUF_READ);
|
|
len = spi_recv();
|
|
if (!len || (len & 0x80)) {
|
|
spi_end();
|
|
return 0;
|
|
}
|
|
if (size > len)
|
|
size = len;
|
|
for (i = 0; i != size; i++)
|
|
((uint8_t *) buf)[i] = spi_recv();
|
|
spi_end();
|
|
return len;
|
|
}
|