RadioLibSmol/src/modules/SX126x.cpp
2019-05-10 15:47:10 +02:00

360 lines
9.8 KiB
C++

#include "SX126x.h"
SX126x::SX126x(Module* mod) : PhysicalLayer(SX126X_CRYSTAL_FREQ, SX126X_DIV_EXPONENT) {
_mod = mod;
_bw = SX126X_LORA_BW_125_0;
_bwKhz = 125.0;
_sf = 9;
_cr = SX126X_LORA_CR_4_7;
_ldro = 0x00;
}
int16_t SX126x::begin(float bw, uint8_t sf, uint8_t cr, uint16_t syncWord, float currentLimit, uint16_t preambleLength) {
// set module properties
_mod->init(USE_SPI, INT_BOTH);
pinMode(_mod->getRx(), INPUT);
// set mode to standby
standby();
// configure settings not accessible by API
config();
// configure publicly accessible settings
int16_t state = setBandwidth(bw);
if(state != ERR_NONE) {
return(state);
}
state = setSpreadingFactor(sf);
if(state != ERR_NONE) {
return(state);
}
state = setCodingRate(cr);
if(state != ERR_NONE) {
return(state);
}
state = setSyncWord(syncWord);
if(state != ERR_NONE) {
return(state);
}
state = setCurrentLimit(currentLimit);
if(state != ERR_NONE) {
return(state);
}
state = setPreambleLength(preambleLength);
if(state != ERR_NONE) {
return(state);
}
return(state);
}
int16_t SX126x::transmit(uint8_t* data, size_t len, uint8_t addr) {
}
int16_t SX126x::receive(uint8_t* data, size_t len) {
}
int16_t SX126x::transmitDirect(uint32_t frf) {
}
int16_t SX126x::receiveDirect() {
}
int16_t SX126x::sleep() {
uint8_t data[] = {SX126X_SLEEP_START_COLD | SX126X_SLEEP_RTC_OFF};
SPIwriteCommand(SX126X_CMD_SET_SLEEP, data, 1);
// wait for SX126x to safely enter sleep mode
delayMicroseconds(500);
return(ERR_NONE);
}
int16_t SX126x::standby(uint8_t mode) {
uint8_t data[] = {mode};
SPIwriteCommand(SX126X_CMD_SET_STANDBY, data, 1);
return(ERR_NONE);
}
int16_t SX126x::setBandwidth(float bw) {
// check active modem
if(getPacketType() != SX126X_PACKET_TYPE_LORA) {
return(ERR_WRONG_MODEM);
}
// check alowed bandwidth values
if(abs(bw - 7.8) <= 0.001) {
_bw = SX126X_LORA_BW_7_8;
} else if(abs(bw - 10.4) <= 0.001) {
_bw = SX126X_LORA_BW_10_4;
} else if(abs(bw - 15.6) <= 0.001) {
_bw = SX126X_LORA_BW_15_6;
} else if(abs(bw - 20.8) <= 0.001) {
_bw = SX126X_LORA_BW_20_8;
} else if(abs(bw - 31.25) <= 0.001) {
_bw = SX126X_LORA_BW_31_25;
} else if(abs(bw - 41.7) <= 0.001) {
_bw = SX126X_LORA_BW_41_7;
} else if(abs(bw - 62.5) <= 0.001) {
_bw = SX126X_LORA_BW_62_5;
} else if(abs(bw - 125.0) <= 0.001) {
_bw = SX126X_LORA_BW_125_0;
} else if(abs(bw - 250.0) <= 0.001) {
_bw = SX126X_LORA_BW_250_0;
} else if(abs(bw - 500.0) <= 0.001) {
_bw = SX126X_LORA_BW_500_0;
} else {
return(ERR_INVALID_BANDWIDTH);
}
// update modulation parameters
_bwKhz = bw;
setModulationParams(_bw, _sf, _cr);
return(ERR_NONE);
}
int16_t SX126x::setSpreadingFactor(uint8_t sf) {
// check active modem
if(getPacketType() != SX126X_PACKET_TYPE_LORA) {
return(ERR_WRONG_MODEM);
}
// check allowed spreading factor values
if(!((sf >= 5) && (sf <= 12))) {
return(ERR_INVALID_SPREADING_FACTOR);
}
// update modulation parameters
_sf = sf;
setModulationParams(_bw, _sf, _cr);
return(ERR_NONE);
}
int16_t SX126x::setCodingRate(uint8_t cr) {
// check active modem
if(getPacketType() != SX126X_PACKET_TYPE_LORA) {
return(ERR_WRONG_MODEM);
}
// check allowed spreading factor values
if(!((cr >= 5) && (cr <= 8))) {
return(ERR_INVALID_CODING_RATE);
}
// update modulation parameters
_cr = cr - 4;
setModulationParams(_bw, _sf, _cr);
return(ERR_NONE);
}
int16_t SX126x::setSyncWord(uint16_t syncWord) {
// check active modem
if(getPacketType() != SX126X_PACKET_TYPE_LORA) {
return(ERR_WRONG_MODEM);
}
// update register
uint8_t data[2] = {(uint8_t)((syncWord >> 8) & 0xFF), (uint8_t)(syncWord & 0xFF)};
writeRegister(SX126X_REG_LORA_SYNC_WORD_MSB, data, 2);
return(ERR_NONE);
}
int16_t SX126x::setCurrentLimit(float currentLimit) {
// calculate raw value
uint8_t rawLimit = (uint8_t)(currentLimit / 2.5);
// update register
writeRegister(SX126X_REG_OCP_CONFIGURATION, &rawLimit, 1);
return(ERR_NONE);
}
int16_t SX126x::setPreambleLength(uint16_t preambleLength) {
// update packet parameters
_preambleLength = preambleLength;
setPacketParams((uint8_t)((_preambleLength >> 8) & 0xFF), (uint8_t)(_preambleLength & 0xFF), _payloadLength, _crcType);
return(ERR_NONE);
}
float SX126x::getDataRate() {
}
int16_t SX126x::setFrequencyDeviation(float freqDev) {
}
void SX126x::setTx(uint32_t timeout) {
uint8_t data[3] = {(uint8_t)((timeout >> 16) & 0xFF), (uint8_t)((timeout >> 8) & 0xFF), (uint8_t)(timeout & 0xFF)};
SPIwriteCommand(SX126X_CMD_SET_TX, data, 3);
}
void SX126x::setRx(uint32_t timeout) {
uint8_t data[3] = {(uint8_t)((timeout >> 16) & 0xFF), (uint8_t)((timeout >> 8) & 0xFF), (uint8_t)(timeout & 0xFF)};
SPIwriteCommand(SX126X_CMD_SET_RX, data, 3);
}
void SX126x::setCad() {
SPIwriteCommand(SX126X_CMD_SET_CAD, NULL, 0);
}
void SX126x::setPaConfig(uint8_t paDutyCycle, uint8_t deviceSel, uint8_t hpMax, uint8_t paLut) {
uint8_t data[4] = {paDutyCycle, deviceSel, hpMax, paLut};
SPIwriteCommand(SX126X_CMD_SET_TX_PARAMS, data, 4);
}
void SX126x::writeRegister(uint16_t addr, uint8_t* data, uint8_t numBytes) {
uint8_t* dat = new uint8_t[2 + numBytes];
dat[0] = (uint8_t)((addr >> 8) & 0xFF);
dat[1] = (uint8_t)(addr & 0xFF);
memcpy(dat + 2, data, numBytes);
SPIwriteCommand(SX126X_CMD_WRITE_REGISTER, dat, 2 + numBytes);
delete[] dat;
}
void SX126x::setDioIrqParams(uint16_t irqMask, uint16_t dio1Mask, uint16_t dio2Mask, uint16_t dio3Mask) {
uint8_t data[8] = {(uint8_t)((irqMask >> 8) & 0xFF), (uint8_t)(irqMask & 0xFF),
(uint8_t)((dio1Mask >> 8) & 0xFF), (uint8_t)(dio1Mask & 0xFF),
(uint8_t)((dio2Mask >> 8) & 0xFF), (uint8_t)(dio2Mask & 0xFF),
(uint8_t)((dio3Mask >> 8) & 0xFF), (uint8_t)(dio3Mask & 0xFF)};
SPIwriteCommand(SX126X_CMD_SET_DIO_IRQ_PARAMS, data, 8);
}
void SX126x::clearIrqStatus(uint16_t clearIrqParams) {
uint8_t data[2] = {(uint8_t)((clearIrqParams >> 8) & 0xFF), (uint8_t)(clearIrqParams & 0xFF)};
SPIwriteCommand(SX126X_CMD_CLEAR_IRQ_STATUS, data, 2);
}
void SX126x::setRfFrequency(uint32_t frf) {
uint8_t data[4] = {(uint8_t)((frf >> 24) & 0xFF), (uint8_t)((frf >> 16) & 0xFF), (uint8_t)((frf >> 8) & 0xFF), (uint8_t)(frf & 0xFF)};
SPIwriteCommand(SX126X_CMD_SET_RF_FREQUENCY, data, 4);
}
uint8_t SX126x::getPacketType() {
uint8_t data[1];
SPIreadCommand(SX126X_CMD_GET_PACKET_TYPE, data, 1);
return(data[0]);
}
void SX126x::setTxParams(uint8_t power, uint8_t rampTime) {
uint8_t data[2] = {power, rampTime};
SPIwriteCommand(SX126X_CMD_SET_TX_PARAMS, data, 2);
}
void SX126x::setModulationParams(uint8_t sf, uint8_t bw, uint8_t cr, uint8_t ldro) {
// calculate symbol length and enable low data rate optimization, if needed
if(ldro == 0xFF) {
float symbolLength = (float)(uint32_t(1) << _sf) / (float)_bwKhz;
if(symbolLength >= 16.0) {
_ldro = SX126X_LORA_LOW_DATA_RATE_OPTIMIZE_ON;
} else {
_ldro = SX126X_LORA_LOW_DATA_RATE_OPTIMIZE_OFF;
}
} else {
_ldro = ldro;
}
uint8_t data[4] = {sf, bw, cr, _ldro};
SPIwriteCommand(SX126X_CMD_SET_MODULATION_PARAMS, data, 4);
}
void SX126x::setPacketParams(uint16_t preambleLength, uint8_t headerType, uint8_t payloadLength, uint8_t crcType, uint8_t invertIQ) {
uint8_t data[7] = {(uint8_t)((preambleLength >> 8) & 0xFF), (uint8_t)(preambleLength & 0xFF), headerType, payloadLength, crcType, invertIQ};
SPIwriteCommand(SX126X_CMD_SET_PACKET_PARAMS, data, 7);
}
uint8_t SX126x::getRssiInt() {
uint8_t data[1];
SPIreadCommand(SX126X_CMD_GET_RSSI_INST, data, 1);
return(data[0]);
}
int16_t SX126x::setFrequencyRaw(float freq) {
// calculate raw value
uint32_t frf = (freq * (uint32_t(1) << SX126X_DIV_EXPONENT)) / SX126X_CRYSTAL_FREQ;
setRfFrequency(frf);
return(ERR_NONE);
}
int16_t SX126x::config() {
// set LoRa mode
uint8_t* data = new uint8_t[1];
data[0] = SX126X_PACKET_TYPE_LORA;
SPIwriteCommand(SX126X_CMD_SET_PACKET_TYPE, data, 1);
// set Rx/Tx fallback mode to STDBY_RC
data[0] = SX126X_RX_TX_FALLBACK_MODE_STDBY_RC;
SPIwriteCommand(SX126X_CMD_SET_RX_TX_FALLBACK_MODE, data, 1);
// set CAD parameters
delete[] data;
data = new uint8_t[7];
data[0] = SX126X_CAD_ON_8_SYMB;
data[1] = _sf + 13;
data[2] = 10;
data[3] = SX126X_CAD_GOTO_STDBY;
data[4] = 0x00;
data[5] = 0x00;
data[6] = 0x00;
SPIwriteCommand(SX126X_CMD_SET_CAD_PARAMS, data, 7);
delete[] data;
return(ERR_NONE);
}
void SX126x::SPIwriteCommand(uint8_t cmd, uint8_t* data, uint8_t numBytes, bool waitForBusy) {
SX126x::SPItransfer(cmd, true, data, NULL, numBytes, waitForBusy);
}
void SX126x::SPIreadCommand(uint8_t cmd, uint8_t* data, uint8_t numBytes, bool waitForBusy) {
SX126x::SPItransfer(cmd, false, NULL, data, numBytes, waitForBusy);
}
void SX126x::SPItransfer(uint8_t cmd, bool write, uint8_t* dataOut, uint8_t* dataIn, uint8_t numBytes, bool waitForBusy) {
// get pointer to used SPI interface
SPIClass* spi = _mod->getSpi();
// ensure BUSY is low (state meachine ready)
// TODO timeout
while(digitalRead(_mod->getRx()));
// start transfer
digitalWrite(_mod->getCs(), LOW);
spi->beginTransaction(SPISettings(2000000, MSBFIRST, SPI_MODE0));
// send command byte
spi->transfer(cmd);
// send/receive all bytes
if(write) {
for(uint8_t n = 0; n < numBytes; n++) {
spi->transfer(dataOut[n]);
}
} else {
// skip the first byte for read-type commands (status-only)
spi->transfer(SX126X_CMD_NOP);
for(uint8_t n = 0; n < numBytes; n++) {
dataIn[n] = spi->transfer(SX126X_CMD_NOP);
}
}
// stop transfer
spi->endTransaction();
digitalWrite(_mod->getCs(), HIGH);
// wait for BUSY to go high and then low
// TODO timeout
if(waitForBusy) {
delayMicroseconds(1);
while(digitalRead(_mod->getRx()));
}
}