px4-firmware/nuttx/drivers/wireless/cc1101/cc1101.c

814 lines
28 KiB
C
Executable File

/****************************************************************************
* drivers/wireless/cc1101/cc1101.c
*
* Copyright (C) 2011 Uros Platise. All rights reserved.
*
* Authors: Uros Platise <uros.platise@isotel.eu>
*
* 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 NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/** \file
* \author Uros Platise
* \brief Chipcon CC1101 Device Driver
*
* Features:
* - Maximum data length: 61 bytes CC1101_PACKET_MAXDATALEN
* - Packet length includes two additional bytes: CC1101_PACKET_MAXTOTALLEN
* - Requires one GDO to trigger end-of-packets in RX and TX modes.
* - Variable packet length with data payload between 1..61 bytes
* (three bytes are reserved for packet length, and RSSI and LQI
* appended at the end of RXFIFO after each reception)
* - Support for General Digital Outputs with overload protection
* (single XOSC pin is allowed, otherwise error is returned)
* - Loadable RF settings, one for ISM Region 1 (Europe) and one for
* ISM Region 2 (Complete America)
*
* Todo:
* - Extend max packet length up to 255 bytes or rather infinite < 4096 bytes
* - Power up/down modes
* - Sequencing between states or add protection for correct termination of
* various different state (so that CC1101 does not block in case of improper use)
*
* \par RSSI and LQI value interpretation
*
* The LQI can be read from the LQI status register or it can be appended
* to the received packet in the RX FIFO. LQI is a metric of the current
* quality of the received signal. The LQI gives an estimate of how easily
* a received signal can be demodulated by accumulating the magnitude of
* the error between ideal constellations and the received signal over
* the 64 symbols immediately following the sync word. LQI is best used
* as a relative measurement of the link quality (a high value indicates
* a better link than what a low value does), since the value is dependent
* on the modulation format.
*
* To simplify: If the received modulation is FSK or GFSK, the receiver
* will measure the frequency of each "bit" and compare it with the
* expected frequency based on the channel frequency and the deviation
* and the measured frequency offset. If other modulations are used, the
* error of the modulated parameter (frequency for FSK/GFSK, phase for
* MSK, amplitude for ASK etc) will be measured against the expected
* ideal value
*
* RSSI (Received Signal Strength Indicator) is a signal strength
* indication. It does not care about the "quality" or "correctness" of
* the signal. LQI does not care about the actual signal strength, but
* the signal quality often is linked to signal strength. This is because
* a strong signal is likely to be less affected by noise and thus will
* be seen as "cleaner" or more "correct" by the receiver.
*
* There are four to five "extreme cases" that can be used to illustrate
* how RSSI and LQI work:
* 1. A weak signal in the presence of noise may give low RSSI and low LQI.
* 2. A weak signal in "total" absence of noise may give low RSSI and high LQI.
* 3. Strong noise (usually coming from an interferer) may give high RSSI and low LQI.
* 4. A strong signal without much noise may give high RSSI and high LQI.
* 5. A very strong signal that causes the receiver to saturate may give
* high RSSI and low LQI.
*
* Note that both RSSI and LQI are best used as relative measurements since
* the values are dependent on the modulation format.
**/
#include <nuttx/config.h>
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>
#include <nuttx/kmalloc.h>
#include <nuttx/wireless/cc1101.h>
/****************************************************************************
* Declarations
****************************************************************************/
#define CC1101_SPIFREQ_BURST 6500000 /* Hz, no delay */
#define CC1101_SPIFREQ_SINGLE 9000000 /* Hz, single access only - no delay */
#define CC1101_MCSM0_VALUE 0x1C
/****************************************************************************
* Chipcon CC1101 Internal Registers
****************************************************************************/
/* Configuration Registers */
#define CC1101_IOCFG2 0x00 /* GDO2 output pin configuration */
#define CC1101_IOCFG1 0x01 /* GDO1 output pin configuration */
#define CC1101_IOCFG0 0x02 /* GDO0 output pin configuration */
#define CC1101_FIFOTHR 0x03 /* RX FIFO and TX FIFO thresholds */
#define CC1101_SYNC1 0x04 /* Sync word, high byte */
#define CC1101_SYNC0 0x05 /* Sync word, low byte */
#define CC1101_PKTLEN 0x06 /* Packet length */
#define CC1101_PKTCTRL1 0x07 /* Packet automation control */
#define CC1101_PKTCTRL0 0x08 /* Packet automation control */
#define CC1101_ADDR 0x09 /* Device address */
#define CC1101_CHANNR 0x0A /* Channel number */
#define CC1101_FSCTRL1 0x0B /* Frequency synthesizer control */
#define CC1101_FSCTRL0 0x0C /* Frequency synthesizer control */
#define CC1101_FREQ2 0x0D /* Frequency control word, high byte */
#define CC1101_FREQ1 0x0E /* Frequency control word, middle byte */
#define CC1101_FREQ0 0x0F /* Frequency control word, low byte */
#define CC1101_MDMCFG4 0x10 /* Modem configuration */
#define CC1101_MDMCFG3 0x11 /* Modem configuration */
#define CC1101_MDMCFG2 0x12 /* Modem configuration */
#define CC1101_MDMCFG1 0x13 /* Modem configuration */
#define CC1101_MDMCFG0 0x14 /* Modem configuration */
#define CC1101_DEVIATN 0x15 /* Modem deviation setting */
#define CC1101_MCSM2 0x16 /* Main Radio Cntrl State Machine config */
#define CC1101_MCSM1 0x17 /* Main Radio Cntrl State Machine config */
#define CC1101_MCSM0 0x18 /* Main Radio Cntrl State Machine config */
#define CC1101_FOCCFG 0x19 /* Frequency Offset Compensation config */
#define CC1101_BSCFG 0x1A /* Bit Synchronization configuration */
#define CC1101_AGCCTRL2 0x1B /* AGC control */
#define CC1101_AGCCTRL1 0x1C /* AGC control */
#define CC1101_AGCCTRL0 0x1D /* AGC control */
#define CC1101_WOREVT1 0x1E /* High byte Event 0 timeout */
#define CC1101_WOREVT0 0x1F /* Low byte Event 0 timeout */
#define CC1101_WORCTRL 0x20 /* Wake On Radio control */
#define CC1101_FREND1 0x21 /* Front end RX configuration */
#define CC1101_FREND0 0x22 /* Front end TX configuration */
#define CC1101_FSCAL3 0x23 /* Frequency synthesizer calibration */
#define CC1101_FSCAL2 0x24 /* Frequency synthesizer calibration */
#define CC1101_FSCAL1 0x25 /* Frequency synthesizer calibration */
#define CC1101_FSCAL0 0x26 /* Frequency synthesizer calibration */
#define CC1101_RCCTRL1 0x27 /* RC oscillator configuration */
#define CC1101_RCCTRL0 0x28 /* RC oscillator configuration */
#define CC1101_FSTEST 0x29 /* Frequency synthesizer cal control */
#define CC1101_PTEST 0x2A /* Production test */
#define CC1101_AGCTEST 0x2B /* AGC test */
#define CC1101_TEST2 0x2C /* Various test settings */
#define CC1101_TEST1 0x2D /* Various test settings */
#define CC1101_TEST0 0x2E /* Various test settings */
/* Status registers */
#define CC1101_PARTNUM (0x30 | 0xc0) /* Part number */
#define CC1101_VERSION (0x31 | 0xc0) /* Current version number */
#define CC1101_FREQEST (0x32 | 0xc0) /* Frequency offset estimate */
#define CC1101_LQI (0x33 | 0xc0) /* Demodulator estimate for link quality */
#define CC1101_RSSI (0x34 | 0xc0) /* Received signal strength indication */
#define CC1101_MARCSTATE (0x35 | 0xc0) /* Control state machine state */
#define CC1101_WORTIME1 (0x36 | 0xc0) /* High byte of WOR timer */
#define CC1101_WORTIME0 (0x37 | 0xc0) /* Low byte of WOR timer */
#define CC1101_PKTSTATUS (0x38 | 0xc0) /* Current GDOx status and packet status */
#define CC1101_VCO_VC_DAC (0x39 | 0xc0) /* Current setting from PLL cal module */
#define CC1101_TXBYTES (0x3A | 0xc0) /* Underflow and # of bytes in TXFIFO */
#define CC1101_RXBYTES (0x3B | 0xc0) /* Overflow and # of bytes in RXFIFO */
#define CC1101_RCCTRL1_STATUS (0x3C | 0xc0) /* Last RC oscilator calibration results */
#define CC1101_RCCTRL0_STATUS (0x3D | 0xc0) /* Last RC oscilator calibration results */
/* Multi byte memory locations */
#define CC1101_PATABLE 0x3E
#define CC1101_TXFIFO 0x3F
#define CC1101_RXFIFO 0x3F
/* Definitions for burst/single access to registers */
#define CC1101_WRITE_BURST 0x40
#define CC1101_READ_SINGLE 0x80
#define CC1101_READ_BURST 0xC0
/* Strobe commands */
#define CC1101_SRES 0x30 /* Reset chip. */
#define CC1101_SFSTXON 0x31 /* Enable and calibrate frequency synthesizer (if MCSM0.FS_AUTOCAL=1). */
#define CC1101_SXOFF 0x32 /* Turn off crystal oscillator. */
#define CC1101_SCAL 0x33 /* Calibrate frequency synthesizer and turn it off */
#define CC1101_SRX 0x34 /* Enable RX. Perform calibration first if switching from IDLE and MCSM0.FS_AUTOCAL=1. */
#define CC1101_STX 0x35 /* Enable TX. Perform calibration first if IDLE and MCSM0.FS_AUTOCAL=1. */
/* If switching from RX state and CCA is enabled then go directly to TX if channel is clear. */
#define CC1101_SIDLE 0x36 /* Exit RX / TX, turn off frequency synthesizer and exit Wake-On-Radio mode if applicable. */
#define CC1101_SAFC 0x37 /* Perform AFC adjustment of the frequency synthesizer */
#define CC1101_SWOR 0x38 /* Start automatic RX polling sequence (Wake-on-Radio) */
#define CC1101_SPWD 0x39 /* Enter power down mode when CSn goes high. */
#define CC1101_SFRX 0x3A /* Flush the RX FIFO buffer. */
#define CC1101_SFTX 0x3B /* Flush the TX FIFO buffer. */
#define CC1101_SWORRST 0x3C /* Reset real time clock. */
#define CC1101_SNOP 0x3D /* No operation. */
/* Modem Control */
#define CC1101_MCSM0_XOSC_FORCE_ON 0x01
/*
* Chip Status Byte
*/
/* Bit fields in the chip status byte */
#define CC1101_STATUS_CHIP_RDYn_BM 0x80
#define CC1101_STATUS_STATE_BM 0x70
#define CC1101_STATUS_FIFO_BYTES_AVAILABLE_BM 0x0F
/* Chip states */
#define CC1101_STATE_MASK 0x70
#define CC1101_STATE_IDLE 0x00
#define CC1101_STATE_RX 0x10
#define CC1101_STATE_TX 0x20
#define CC1101_STATE_FSTXON 0x30
#define CC1101_STATE_CALIBRATE 0x40
#define CC1101_STATE_SETTLING 0x50
#define CC1101_STATE_RX_OVERFLOW 0x60
#define CC1101_STATE_TX_UNDERFLOW 0x70
/* Values of the MACRSTATE register */
#define CC1101_MARCSTATE_SLEEP 0x00
#define CC1101_MARCSTATE_IDLE 0x01
#define CC1101_MARCSTATE_XOFF 0x02
#define CC1101_MARCSTATE_VCOON_MC 0x03
#define CC1101_MARCSTATE_REGON_MC 0x04
#define CC1101_MARCSTATE_MANCAL 0x05
#define CC1101_MARCSTATE_VCOON 0x06
#define CC1101_MARCSTATE_REGON 0x07
#define CC1101_MARCSTATE_STARTCAL 0x08
#define CC1101_MARCSTATE_BWBOOST 0x09
#define CC1101_MARCSTATE_FS_LOCK 0x0A
#define CC1101_MARCSTATE_IFADCON 0x0B
#define CC1101_MARCSTATE_ENDCAL 0x0C
#define CC1101_MARCSTATE_RX 0x0D
#define CC1101_MARCSTATE_RX_END 0x0E
#define CC1101_MARCSTATE_RX_RST 0x0F
#define CC1101_MARCSTATE_TXRX_SWITCH 0x10
#define CC1101_MARCSTATE_RXFIFO_OVERFLOW 0x11
#define CC1101_MARCSTATE_FSTXON 0x12
#define CC1101_MARCSTATE_TX 0x13
#define CC1101_MARCSTATE_TX_END 0x14
#define CC1101_MARCSTATE_RXTX_SWITCH 0x15
#define CC1101_MARCSTATE_TXFIFO_UNDERFLOW 0x16
/* Part number and version */
#define CC1101_PARTNUM_VALUE 0x00
#define CC1101_VERSION_VALUE 0x04
/*
* Others ...
*/
#define CC1101_LQI_CRC_OK_BM 0x80
#define CC1101_LQI_EST_BM 0x7F
/****************************************************************************
* Private Data Types
****************************************************************************/
#define FLAGS_RXONLY 1 /* Indicates receive operation only */
#define FLAGS_XOSCENABLED 2 /* Indicates that one pin is configured as XOSC/n */
struct cc1101_dev_s {
const struct c1101_rfsettings_s *rfsettings;
struct spi_dev_s * spi;
uint8_t isrpin; /* CC1101 pin used to trigger interrupts */
uint32_t pinset; /* GPIO of the MCU */
uint8_t flags;
uint8_t channel;
uint8_t power;
};
/****************************************************************************
* Private Functions
****************************************************************************/
void cc1101_access_begin(struct cc1101_dev_s * dev)
{
SPI_LOCK(dev->spi, true);
SPI_SELECT(dev->spi, SPIDEV_WIRELESS, true);
SPI_SETMODE(dev->spi, SPIDEV_MODE0); /* CPOL=0, CPHA=0 */
SPI_SETBITS(dev->spi, 8);
}
void cc1101_access_end(struct cc1101_dev_s * dev)
{
SPI_SELECT(dev->spi, SPIDEV_WIRELESS, false);
SPI_LOCK(dev->spi, false);
}
/** CC1101 Access with Range Check
*
* \param dev CC1101 Private Structure
* \param addr CC1101 Address
* \param buf Pointer to buffer, either for read or write access
* \param length when >0 it denotes read access, when <0 it denotes write
* access of -length. abs(length) greater of 1 implies burst mode,
* however
* \return OK on success or errno is set.
*/
int cc1101_access(struct cc1101_dev_s * dev, uint8_t addr, uint8_t *buf, int length)
{
int stabyte;
/* Address cannot explicitly define READ command while length WRITE.
* Also access to these cells is only permitted as one byte, eventhough
* transfer is marked as BURST!
*/
if ( (addr & CC1101_READ_SINGLE) && length != 1 )
return ERROR;
/* Prepare SPI */
cc1101_access_begin(dev);
if (length>1 || length < -1)
SPI_SETFREQUENCY(dev->spi, CC1101_SPIFREQ_BURST);
else SPI_SETFREQUENCY(dev->spi, CC1101_SPIFREQ_SINGLE);
/* Transfer */
if (length <= 0) { /* 0 length are command strobes */
if (length < -1)
addr |= CC1101_WRITE_BURST;
stabyte = SPI_SEND(dev->spi, addr);
if (length) {
SPI_SNDBLOCK(dev->spi, buf, -length);
}
}
else {
addr |= CC1101_READ_SINGLE;
if (length > 1)
addr |= CC1101_READ_BURST;
stabyte = SPI_SEND(dev->spi, addr);
SPI_RECVBLOCK(dev->spi, buf, length);
}
cc1101_access_end(dev);
return stabyte;
}
/** Strobes command and returns chip status byte
*
* By default commands are send as Write. To a command,
* CC1101_READ_SINGLE may be OR'ed to obtain the number of RX bytes
* pending in RX FIFO.
*/
inline uint8_t cc1101_strobe(struct cc1101_dev_s * dev, uint8_t command)
{
uint8_t status;
cc1101_access_begin(dev);
SPI_SETFREQUENCY(dev->spi, CC1101_SPIFREQ_SINGLE);
status = SPI_SEND(dev->spi, command);
cc1101_access_end(dev);
return status;
}
int cc1101_reset(struct cc1101_dev_s * dev)
{
cc1101_strobe(dev, CC1101_SRES);
return OK;
}
int cc1101_checkpart(struct cc1101_dev_s * dev)
{
uint8_t partnum, version;
if (cc1101_access(dev, CC1101_PARTNUM, &partnum, 1) < 0 ||
cc1101_access(dev, CC1101_VERSION, &version, 1) < 0)
return ERROR;
if (partnum == CC1101_PARTNUM_VALUE && version == CC1101_VERSION_VALUE)
return OK;
return ERROR;
}
void cc1101_dumpregs(struct cc1101_dev_s * dev, uint8_t addr, uint8_t length)
{
uint8_t buf[0x30], i;
cc1101_access(dev, addr, buf, length);
printf("CC1101[%2x]: ", addr);
for (i=0; i<length; i++) printf(" %2x,", buf[i]);
printf("\n");
}
void cc1101_setpacketctrl(struct cc1101_dev_s * dev)
{
uint8_t values[3];
values[0] = 0; /* Rx FIFO threshold = 32, Tx FIFO threshold = 33 */
cc1101_access(dev, CC1101_FIFOTHR, values, -1);
/* Packet length
* Limit it to 61 bytes in total: pktlen, data[61], rssi, lqi
*/
values[0] = CC1101_PACKET_MAXDATALEN;
cc1101_access(dev, CC1101_PKTLEN, values, -1);
/* Packet Control */
values[0] = 0x04; /* Append status: RSSI and LQI at the end of received packet */
/* TODO: CRC Auto Flash bit 0x08 ??? */
values[1] = 0x05; /* CRC in Rx and Tx Enabled: Variable Packet mode, defined by first byte */
/* TODO: Enable data whitening ... */
cc1101_access(dev, CC1101_PKTCTRL1, values, -2);
/* Main Radio Control State Machine */
values[0] = 0x07; /* No time-out */
values[1] = 0x00; /* Clear channel if RSSI < thr && !receiving;
* TX -> RX, RX -> RX: 0x3F */
values[2] = CC1101_MCSM0_VALUE; /* Calibrate on IDLE -> RX/TX, OSC Timeout = ~500 us
TODO: has XOSC_FORCE_ON */
cc1101_access(dev, CC1101_MCSM2, values, -3);
/* Wake-On Radio Control */
// Not used yet.
// WOREVT1:WOREVT0 - 16-bit timeout register
}
/****************************************************************************
* Callbacks
****************************************************************************/
volatile int cc1101_interrupt = 0;
/** External line triggers this callback
*
* The concept todo is:
* - GPIO provides EXTI Interrupt
* - It should handle EXTI Interrupts in ISR, to which chipcon can
* register a callback (and others). The ISR then foreach() calls a
* its callback, and it is up to peripheral to find, whether the cause
* of EXTI ISR was itself.
**/
int cc1101_eventcb(int irq, FAR void *context)
{
cc1101_interrupt++;
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
struct cc1101_dev_s * cc1101_init(struct spi_dev_s * spi, uint8_t isrpin,
uint32_t pinset, const struct c1101_rfsettings_s * rfsettings)
{
struct cc1101_dev_s * dev;
ASSERT(spi);
if ( (dev = kmalloc( sizeof(struct cc1101_dev_s) )) == NULL) {
errno = ENOMEM;
return NULL;
}
dev->rfsettings = rfsettings;
dev->spi = spi;
dev->isrpin = isrpin;
dev->pinset = pinset;
dev->flags = 0;
dev->channel = rfsettings->CHMIN;
dev->power = rfsettings->PAMAX;
/* Reset chip, check status bytes */
if ( cc1101_reset(dev) < 0 ) {
kfree(dev);
errno = EFAULT;
return NULL;
}
/* Check part compatibility */
if ( cc1101_checkpart(dev) < 0 ) {
kfree(dev);
errno = ENODEV;
return NULL;
}
/* Configure CC1101:
* - disable GDOx for best performance
* - load RF
* - and packet control
*/
cc1101_setgdo(dev, CC1101_PIN_GDO0, CC1101_GDO_HIZ);
cc1101_setgdo(dev, CC1101_PIN_GDO1, CC1101_GDO_HIZ);
cc1101_setgdo(dev, CC1101_PIN_GDO2, CC1101_GDO_HIZ);
cc1101_setrf(dev, rfsettings);
cc1101_setpacketctrl(dev);
/* Set the ISR to be triggerred on falling edge of the:
*
* 6 (0x06) Asserts when sync word has been sent / received, and
* de-asserts at the end of the packet. In RX, the pin will de-assert
* when the optional address check fails or the RX FIFO overflows.
* In TX the pin will de-assert if the TX FIFO underflows.
*/
cc1101_setgdo(dev, dev->isrpin, CC1101_GDO_SYNC);
/* Bind to external interrupt line */
// depends on STM32: TODO: Make that config within pinset and
// provide general gpio interface
//stm32_gpiosetevent(pinset, false, true, true, cc1101_eventcb);
return dev;
}
int cc1101_deinit(struct cc1101_dev_s * dev)
{
ASSERT(dev);
/* Release interrupt */
//stm32_gpiosetevent(pinset, false, false, false, NULL);
/* Power down chip */
cc1101_powerdown(dev);
/* Release external interrupt line */
kfree(dev);
return 0;
}
int cc1101_powerup(struct cc1101_dev_s * dev)
{
ASSERT(dev);
return 0;
}
int cc1101_powerdown(struct cc1101_dev_s * dev)
{
ASSERT(dev);
return 0;
}
int cc1101_setgdo(struct cc1101_dev_s * dev, uint8_t pin, uint8_t function)
{
ASSERT(dev);
ASSERT(pin <= CC1101_IOCFG0);
if (function >= CC1101_GDO_CLK_XOSC1) {
/* Only one pin can be enabled at a time as XOSC/n */
if (dev->flags & FLAGS_XOSCENABLED) return -EPERM;
/* Force XOSC to stay active even in sleep mode */
int value = CC1101_MCSM0_VALUE | CC1101_MCSM0_XOSC_FORCE_ON;
cc1101_access(dev, CC1101_MCSM0, &value, -1);
dev->flags |= FLAGS_XOSCENABLED;
}
else if (dev->flags & FLAGS_XOSCENABLED) {
/* Disable XOSC in sleep mode */
int value = CC1101_MCSM0_VALUE;
cc1101_access(dev, CC1101_MCSM0, &value, -1);
dev->flags &= ~FLAGS_XOSCENABLED;
}
return cc1101_access(dev, pin, &function, -1);
}
int cc1101_setrf(struct cc1101_dev_s * dev, const struct c1101_rfsettings_s *settings)
{
ASSERT(dev);
ASSERT(settings);
if (cc1101_access(dev, CC1101_FSCTRL1, &settings->FSCTRL1, -11) < 0) return ERROR;
if (cc1101_access(dev, CC1101_FOCCFG, &settings->FOCCFG, -5) < 0) return ERROR;
if (cc1101_access(dev, CC1101_FREND1, &settings->FREND1, -6) < 0) return ERROR;
/* Load Power Table */
if (cc1101_access(dev, CC1101_PATABLE, settings->PA, -8) < 0) return ERROR;
/* If channel is out of valid range, mark that. Limit power.
* We are not allowed to send any data, but are allowed to listen
* and receive.
*/
cc1101_setchannel(dev, dev->channel);
cc1101_setpower(dev, dev->power);
return OK;
}
int cc1101_setchannel(struct cc1101_dev_s * dev, uint8_t channel)
{
ASSERT(dev);
/* Store localy in further checks */
dev->channel = channel;
/* If channel is out of valid, we are allowed to listen and receive only */
if (channel < dev->rfsettings->CHMIN || channel > dev->rfsettings->CHMAX)
dev->flags |= FLAGS_RXONLY;
else dev->flags &= ~FLAGS_RXONLY;
cc1101_access(dev, CC1101_CHANNR, &dev->channel, -1);
return dev->flags & FLAGS_RXONLY;
}
uint8_t cc1101_setpower(struct cc1101_dev_s * dev, uint8_t power)
{
ASSERT(dev);
if (power > dev->rfsettings->PAMAX)
power = dev->rfsettings->PAMAX;
dev->power = power;
if (power == 0) {
dev->flags |= FLAGS_RXONLY;
return 0;
}
else dev->flags &= ~FLAGS_RXONLY;
/* Add remaining part from RF table (to get rid of readback) */
power--;
power |= dev->rfsettings->FREND0;
/* On error, report that as zero power */
if (cc1101_access(dev, CC1101_FREND0, &power, -1) < 0)
dev->power = 0;
return dev->power;
}
int cc1101_calcRSSIdBm(int rssi)
{
if (rssi >= 128) rssi -= 256;
return (rssi >> 1) - 74;
}
int cc1101_receive(struct cc1101_dev_s * dev)
{
ASSERT(dev);
/* \todo Wait for IDLE before going into another state? */
cc1101_interrupt = 0;
cc1101_strobe(dev, CC1101_SRX | CC1101_READ_SINGLE);
return 0;
}
int cc1101_read(struct cc1101_dev_s * dev, uint8_t * buf, size_t size)
{
ASSERT(dev);
if (buf==NULL) {
if (size==0) return 64;
// else received packet size
return 0;
}
if (cc1101_interrupt == 0) return 0;
int status = cc1101_strobe(dev, CC1101_SNOP | CC1101_READ_SINGLE);
if (status & CC1101_STATUS_FIFO_BYTES_AVAILABLE_BM &&
(status & CC1101_STATE_MASK) == CC1101_STATE_IDLE) {
uint8_t nbytes;
cc1101_access(dev, CC1101_RXFIFO, &nbytes, 1);
nbytes += 2; /* RSSI and LQI */
cc1101_access(dev, CC1101_RXFIFO, buf, (nbytes > size) ? size : nbytes);
/* Flush remaining bytes, if there is no room to receive
* or if there is a BAD CRC
*/
if (nbytes > size || (nbytes <= size && !(buf[nbytes-1]&0x80)) ) {
printf("Flushing RX FIFO\n");
cc1101_strobe(dev, CC1101_SFRX);
}
return nbytes;
}
return 0;
}
int cc1101_write(struct cc1101_dev_s * dev, const uint8_t * buf, size_t size)
{
uint8_t packetlen;
ASSERT(dev);
ASSERT(buf);
if (dev->flags & FLAGS_RXONLY) return -EPERM;
/* Present limit */
if (size > CC1101_PACKET_MAXDATALEN)
packetlen = CC1101_PACKET_MAXDATALEN;
else packetlen = size;
cc1101_access(dev, CC1101_TXFIFO, &packetlen, -1);
cc1101_access(dev, CC1101_TXFIFO, buf, -size);
return 0;
}
int cc1101_send(struct cc1101_dev_s * dev)
{
ASSERT(dev);
if (dev->flags & FLAGS_RXONLY) return -EPERM;
cc1101_interrupt = 0;
cc1101_strobe(dev, CC1101_STX);
/* wait until send, going to IDLE */
while( cc1101_interrupt == 0 );
return 0;
}
int cc1101_idle(struct cc1101_dev_s * dev)
{
ASSERT(dev);
cc1101_strobe(dev, CC1101_SIDLE);
return 0;
}