RadioLibSmol/src/modules/SX127x/SX1278.cpp

626 lines
18 KiB
C++

#include "SX1278.h"
#if !defined(RADIOLIB_EXCLUDE_SX127X)
SX1278::SX1278(Module* mod) : SX127x(mod) {
}
int16_t SX1278::begin(float freq, float bw, uint8_t sf, uint8_t cr, uint8_t syncWord, int8_t power, uint16_t preambleLength, uint8_t gain) {
// execute common part
int16_t state = SX127x::begin(SX1278_CHIP_VERSION, syncWord, preambleLength);
RADIOLIB_ASSERT(state);
// configure publicly accessible settings
state = setBandwidth(bw);
RADIOLIB_ASSERT(state);
state = setFrequency(freq);
RADIOLIB_ASSERT(state);
state = setSpreadingFactor(sf);
RADIOLIB_ASSERT(state);
state = setCodingRate(cr);
RADIOLIB_ASSERT(state);
state = setOutputPower(power);
RADIOLIB_ASSERT(state);
state = setGain(gain);
RADIOLIB_ASSERT(state);
return(state);
}
int16_t SX1278::beginFSK(float freq, float br, float freqDev, float rxBw, int8_t power, uint16_t preambleLength, bool enableOOK) {
// execute common part
int16_t state = SX127x::beginFSK(SX1278_CHIP_VERSION, br, freqDev, rxBw, preambleLength, enableOOK);
RADIOLIB_ASSERT(state);
// configure settings not accessible by API
state = configFSK();
RADIOLIB_ASSERT(state);
// configure publicly accessible settings
state = setFrequency(freq);
RADIOLIB_ASSERT(state);
state = setOutputPower(power);
RADIOLIB_ASSERT(state);
if(enableOOK) {
state = setDataShapingOOK(RADIOLIB_SHAPING_NONE);
RADIOLIB_ASSERT(state);
} else {
state = setDataShaping(RADIOLIB_SHAPING_NONE);
RADIOLIB_ASSERT(state);
}
return(state);
}
void SX1278::reset() {
Module::pinMode(_mod->getRst(), OUTPUT);
Module::digitalWrite(_mod->getRst(), LOW);
Module::delay(1);
Module::digitalWrite(_mod->getRst(), HIGH);
Module::delay(5);
}
int16_t SX1278::setFrequency(float freq) {
RADIOLIB_CHECK_RANGE(freq, 137.0, 525.0, ERR_INVALID_FREQUENCY);
// set frequency and if successful, save the new setting
int16_t state = SX127x::setFrequencyRaw(freq);
if(state == ERR_NONE) {
SX127x::_freq = freq;
}
return(state);
}
int16_t SX1278::setBandwidth(float bw) {
// check active modem
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
uint8_t newBandwidth;
// check allowed bandwidth values
if(fabs(bw - 7.8) <= 0.001) {
newBandwidth = SX1278_BW_7_80_KHZ;
} else if(fabs(bw - 10.4) <= 0.001) {
newBandwidth = SX1278_BW_10_40_KHZ;
} else if(fabs(bw - 15.6) <= 0.001) {
newBandwidth = SX1278_BW_15_60_KHZ;
} else if(fabs(bw - 20.8) <= 0.001) {
newBandwidth = SX1278_BW_20_80_KHZ;
} else if(fabs(bw - 31.25) <= 0.001) {
newBandwidth = SX1278_BW_31_25_KHZ;
} else if(fabs(bw - 41.7) <= 0.001) {
newBandwidth = SX1278_BW_41_70_KHZ;
} else if(fabs(bw - 62.5) <= 0.001) {
newBandwidth = SX1278_BW_62_50_KHZ;
} else if(fabs(bw - 125.0) <= 0.001) {
newBandwidth = SX1278_BW_125_00_KHZ;
} else if(fabs(bw - 250.0) <= 0.001) {
newBandwidth = SX1278_BW_250_00_KHZ;
} else if(fabs(bw - 500.0) <= 0.001) {
newBandwidth = SX1278_BW_500_00_KHZ;
} else {
return(ERR_INVALID_BANDWIDTH);
}
// set bandwidth and if successful, save the new setting
int16_t state = SX1278::setBandwidthRaw(newBandwidth);
if(state == ERR_NONE) {
SX127x::_bw = bw;
// calculate symbol length and set low data rate optimization, if auto-configuration is enabled
if(_ldroAuto) {
float symbolLength = (float)(uint32_t(1) << SX127x::_sf) / (float)SX127x::_bw;
RADIOLIB_DEBUG_PRINT("Symbol length: ");
RADIOLIB_DEBUG_PRINT(symbolLength);
RADIOLIB_DEBUG_PRINTLN(" ms");
if(symbolLength >= 16.0) {
state = _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_ON, 3, 3);
} else {
state = _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_OFF, 3, 3);
}
}
}
return(state);
}
int16_t SX1278::setSpreadingFactor(uint8_t sf) {
// check active modem
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
uint8_t newSpreadingFactor;
// check allowed spreading factor values
switch(sf) {
case 6:
newSpreadingFactor = SX127X_SF_6;
break;
case 7:
newSpreadingFactor = SX127X_SF_7;
break;
case 8:
newSpreadingFactor = SX127X_SF_8;
break;
case 9:
newSpreadingFactor = SX127X_SF_9;
break;
case 10:
newSpreadingFactor = SX127X_SF_10;
break;
case 11:
newSpreadingFactor = SX127X_SF_11;
break;
case 12:
newSpreadingFactor = SX127X_SF_12;
break;
default:
return(ERR_INVALID_SPREADING_FACTOR);
}
// set spreading factor and if successful, save the new setting
int16_t state = SX1278::setSpreadingFactorRaw(newSpreadingFactor);
if(state == ERR_NONE) {
SX127x::_sf = sf;
// calculate symbol length and set low data rate optimization, if auto-configuration is enabled
if(_ldroAuto) {
float symbolLength = (float)(uint32_t(1) << SX127x::_sf) / (float)SX127x::_bw;
RADIOLIB_DEBUG_PRINT("Symbol length: ");
RADIOLIB_DEBUG_PRINT(symbolLength);
RADIOLIB_DEBUG_PRINTLN(" ms");
if(symbolLength >= 16.0) {
state = _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_ON, 3, 3);
} else {
state = _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_OFF, 3, 3);
}
}
}
return(state);
}
int16_t SX1278::setCodingRate(uint8_t cr) {
// check active modem
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
uint8_t newCodingRate;
// check allowed coding rate values
switch(cr) {
case 5:
newCodingRate = SX1278_CR_4_5;
break;
case 6:
newCodingRate = SX1278_CR_4_6;
break;
case 7:
newCodingRate = SX1278_CR_4_7;
break;
case 8:
newCodingRate = SX1278_CR_4_8;
break;
default:
return(ERR_INVALID_CODING_RATE);
}
// set coding rate and if successful, save the new setting
int16_t state = SX1278::setCodingRateRaw(newCodingRate);
if(state == ERR_NONE) {
SX127x::_cr = cr;
}
return(state);
}
int16_t SX1278::setOutputPower(int8_t power, bool useRfo) {
// check allowed power range
if(useRfo) {
// RFO output
RADIOLIB_CHECK_RANGE(power, -3, 15, ERR_INVALID_OUTPUT_POWER);
} else {
// PA_BOOST output, check high-power operation
if(power != 20) {
RADIOLIB_CHECK_RANGE(power, 2, 17, ERR_INVALID_OUTPUT_POWER);
}
}
// set mode to standby
int16_t state = SX127x::standby();
if(useRfo) {
uint8_t paCfg = 0;
if(power < 0) {
// low power mode RFO output
paCfg = SX1278_LOW_POWER | (power + 3);
} else {
// high power mode RFO output
paCfg = SX1278_MAX_POWER | power;
}
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, SX127X_PA_SELECT_RFO, 7, 7);
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, paCfg, 6, 0);
state |= _mod->SPIsetRegValue(SX1278_REG_PA_DAC, SX127X_PA_BOOST_OFF, 2, 0);
} else {
if(power != 20) {
// power is 2 - 17 dBm, enable PA1 + PA2 on PA_BOOST
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, SX127X_PA_SELECT_BOOST, 7, 7);
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, SX1278_MAX_POWER | (power - 2), 6, 0);
state |= _mod->SPIsetRegValue(SX1278_REG_PA_DAC, SX127X_PA_BOOST_OFF, 2, 0);
} else {
// power is 20 dBm, enable PA1 + PA2 on PA_BOOST and enable high power control
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, SX127X_PA_SELECT_BOOST, 7, 7);
state |= _mod->SPIsetRegValue(SX127X_REG_PA_CONFIG, SX1278_MAX_POWER | 0x0F, 6, 0);
state |= _mod->SPIsetRegValue(SX1278_REG_PA_DAC, SX127X_PA_BOOST_ON, 2, 0);
}
}
return(state);
}
int16_t SX1278::setGain(uint8_t gain) {
// check allowed range
if(gain > 6) {
return(ERR_INVALID_GAIN);
}
// set mode to standby
int16_t state = SX127x::standby();
// get modem
int16_t modem = getActiveModem();
if(modem == SX127X_LORA){
// set gain
if(gain == 0) {
// gain set to 0, enable AGC loop
state |= _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_AGC_AUTO_ON, 2, 2);
} else {
state |= _mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_AGC_AUTO_OFF, 2, 2);
state |= _mod->SPIsetRegValue(SX127X_REG_LNA, (gain << 5) | SX127X_LNA_BOOST_ON);
}
} else if(modem == SX127X_FSK_OOK) {
// set gain
if(gain == 0) {
// gain set to 0, enable AGC loop
state |= _mod->SPIsetRegValue(SX127X_REG_RX_CONFIG, SX127X_AGC_AUTO_ON, 3, 3);
} else {
state |= _mod->SPIsetRegValue(SX127X_REG_RX_CONFIG, SX127X_AGC_AUTO_ON, 3, 3);
state |= _mod->SPIsetRegValue(SX127X_REG_LNA, (gain << 5) | SX127X_LNA_BOOST_ON);
}
}
return(state);
}
int16_t SX1278::setDataShaping(uint8_t sh) {
// check active modem
if(getActiveModem() != SX127X_FSK_OOK) {
return(ERR_WRONG_MODEM);
}
// check modulation
if(SX127x::_ook) {
return(ERR_INVALID_MODULATION);
}
// set mode to standby
int16_t state = SX127x::standby();
RADIOLIB_ASSERT(state);
// set data shaping
switch(sh) {
case RADIOLIB_SHAPING_NONE:
return(_mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_NO_SHAPING, 6, 5));
case RADIOLIB_SHAPING_0_3:
return(_mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_FSK_GAUSSIAN_0_3, 6, 5));
case RADIOLIB_SHAPING_0_5:
return(_mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_FSK_GAUSSIAN_0_5, 6, 5));
case RADIOLIB_SHAPING_1_0:
return(_mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_FSK_GAUSSIAN_1_0, 6, 5));
default:
return(ERR_INVALID_DATA_SHAPING);
}
}
int16_t SX1278::setDataShapingOOK(uint8_t sh) {
// check active modem
if(getActiveModem() != SX127X_FSK_OOK) {
return(ERR_WRONG_MODEM);
}
// check modulation
if(!SX127x::_ook) {
return(ERR_INVALID_MODULATION);
}
// set mode to standby
int16_t state = SX127x::standby();
// set data shaping
switch(sh) {
case 0:
state |= _mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_NO_SHAPING, 6, 5);
break;
case 1:
state |= _mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_OOK_FILTER_BR, 6, 5);
break;
case 2:
state |= _mod->SPIsetRegValue(SX127X_REG_PA_RAMP, SX1278_OOK_FILTER_2BR, 6, 5);
break;
default:
return(ERR_INVALID_DATA_SHAPING);
}
return(state);
}
float SX1278::getRSSI(bool skipReceive) {
if(getActiveModem() == SX127X_LORA) {
// for LoRa, get RSSI of the last packet
float lastPacketRSSI;
// RSSI calculation uses different constant for low-frequency and high-frequency ports
if(_freq < 868.0) {
lastPacketRSSI = -164 + _mod->SPIgetRegValue(SX127X_REG_PKT_RSSI_VALUE);
} else {
lastPacketRSSI = -157 + _mod->SPIgetRegValue(SX127X_REG_PKT_RSSI_VALUE);
}
// spread-spectrum modulation signal can be received below noise floor
// check last packet SNR and if it's less than 0, add it to reported RSSI to get the correct value
float lastPacketSNR = SX127x::getSNR();
if(lastPacketSNR < 0.0) {
lastPacketRSSI += lastPacketSNR;
}
return(lastPacketRSSI);
} else {
// enable listen mode
if(!skipReceive) {
startReceive();
}
// read the value for FSK
float rssi = (float)_mod->SPIgetRegValue(SX127X_REG_RSSI_VALUE_FSK) / -2.0;
// set mode back to standby
if(!skipReceive) {
standby();
}
// return the value
return(rssi);
}
}
int16_t SX1278::setCRC(bool enable, bool mode) {
if(getActiveModem() == SX127X_LORA) {
// set LoRa CRC
SX127x::_crcEnabled = enable;
if(enable) {
return(_mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_2, SX1278_RX_CRC_MODE_ON, 2, 2));
} else {
return(_mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_2, SX1278_RX_CRC_MODE_OFF, 2, 2));
}
} else {
// set FSK CRC
int16_t state = ERR_NONE;
if(enable) {
state = _mod->SPIsetRegValue(SX127X_REG_PACKET_CONFIG_1, SX127X_CRC_ON, 4, 4);
} else {
state = _mod->SPIsetRegValue(SX127X_REG_PACKET_CONFIG_1, SX127X_CRC_OFF, 4, 4);
}
RADIOLIB_ASSERT(state);
// set FSK CRC mode
if(mode) {
return(_mod->SPIsetRegValue(SX127X_REG_PACKET_CONFIG_1, SX127X_CRC_WHITENING_TYPE_IBM, 0, 0));
} else {
return(_mod->SPIsetRegValue(SX127X_REG_PACKET_CONFIG_1, SX127X_CRC_WHITENING_TYPE_CCITT, 0, 0));
}
}
}
int16_t SX1278::forceLDRO(bool enable) {
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
_ldroAuto = false;
if(enable) {
return(_mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_ON, 3, 3));
} else {
return(_mod->SPIsetRegValue(SX1278_REG_MODEM_CONFIG_3, SX1278_LOW_DATA_RATE_OPT_OFF, 3, 3));
}
}
int16_t SX1278::autoLDRO() {
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
_ldroAuto = true;
return(ERR_NONE);
}
int16_t SX1278::implicitHeader(size_t len) {
return(setHeaderType(SX1278_HEADER_IMPL_MODE, len));
}
int16_t SX1278::explicitHeader() {
return(setHeaderType(SX1278_HEADER_EXPL_MODE));
}
int16_t SX1278::setBandwidthRaw(uint8_t newBandwidth) {
// set mode to standby
int16_t state = SX127x::standby();
// write register
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_1, newBandwidth, 7, 4);
return(state);
}
int16_t SX1278::setSpreadingFactorRaw(uint8_t newSpreadingFactor) {
// set mode to standby
int16_t state = SX127x::standby();
// write registers
if(newSpreadingFactor == SX127X_SF_6) {
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_1, SX1278_HEADER_IMPL_MODE, 0, 0);
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_2, SX127X_SF_6 | SX127X_TX_MODE_SINGLE | (SX127x::_crcEnabled ? SX1278_RX_CRC_MODE_ON : SX1278_RX_CRC_MODE_OFF), 7, 2);
state |= _mod->SPIsetRegValue(SX127X_REG_DETECT_OPTIMIZE, SX127X_DETECT_OPTIMIZE_SF_6, 2, 0);
state |= _mod->SPIsetRegValue(SX127X_REG_DETECTION_THRESHOLD, SX127X_DETECTION_THRESHOLD_SF_6);
} else {
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_1, SX1278_HEADER_EXPL_MODE, 0, 0);
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_2, newSpreadingFactor | SX127X_TX_MODE_SINGLE | (SX127x::_crcEnabled ? SX1278_RX_CRC_MODE_ON : SX1278_RX_CRC_MODE_OFF), 7, 2);
state |= _mod->SPIsetRegValue(SX127X_REG_DETECT_OPTIMIZE, SX127X_DETECT_OPTIMIZE_SF_7_12, 2, 0);
state |= _mod->SPIsetRegValue(SX127X_REG_DETECTION_THRESHOLD, SX127X_DETECTION_THRESHOLD_SF_7_12);
}
return(state);
}
int16_t SX1278::setCodingRateRaw(uint8_t newCodingRate) {
// set mode to standby
int16_t state = SX127x::standby();
// write register
state |= _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_1, newCodingRate, 3, 1);
return(state);
}
int16_t SX1278::setHeaderType(uint8_t headerType, size_t len) {
// check active modem
if(getActiveModem() != SX127X_LORA) {
return(ERR_WRONG_MODEM);
}
// set requested packet mode
int16_t state = _mod->SPIsetRegValue(SX127X_REG_MODEM_CONFIG_1, headerType, 0, 0);
RADIOLIB_ASSERT(state);
// set length to register
state = _mod->SPIsetRegValue(SX127X_REG_PAYLOAD_LENGTH, len);
RADIOLIB_ASSERT(state);
// update cached value
_packetLength = len;
return(state);
}
int16_t SX1278::configFSK() {
// configure common registers
int16_t state = SX127x::configFSK();
RADIOLIB_ASSERT(state);
// set fast PLL hop
state = _mod->SPIsetRegValue(SX1278_REG_PLL_HOP, SX127X_FAST_HOP_ON, 7, 7);
return(state);
}
void SX1278::errataFix(bool rx) {
// only apply in LoRa mode
if(getActiveModem() != SX127X_LORA) {
return;
}
// sensitivity optimization for 500kHz bandwidth
// see SX1276/77/78 Errata, section 2.1 for details
if(fabs(_bw - 500.0) <= 0.001) {
if((_freq >= 862.0) && (_freq <= 1020.0)) {
_mod->SPIwriteRegister(0x36, 0x02);
_mod->SPIwriteRegister(0x3a, 0x64);
} else if((_freq >= 410.0) && (_freq <= 525.0)) {
_mod->SPIwriteRegister(0x36, 0x02);
_mod->SPIwriteRegister(0x3a, 0x7F);
}
}
// mitigation of receiver spurious response
// see SX1276/77/78 Errata, section 2.3 for details
// figure out what we need to set
uint8_t fixedRegs[3] = { 0x00, 0x00, 0x00 };
float rxFreq = _freq;
if(fabs(_bw - 7.8) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x48;
fixedRegs[2] = 0x00;
rxFreq += 0.00781;
} else if(fabs(_bw - 10.4) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x44;
fixedRegs[2] = 0x00;
rxFreq += 0.01042;
} else if(fabs(_bw - 15.6) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x44;
fixedRegs[2] = 0x00;
rxFreq += 0.01562;
} else if(fabs(_bw - 20.8) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x44;
fixedRegs[2] = 0x00;
rxFreq += 0.02083;
} else if(fabs(_bw - 31.25) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x44;
fixedRegs[2] = 0x00;
rxFreq += 0.03125;
} else if(fabs(_bw - 41.7) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x44;
fixedRegs[2] = 0x00;
rxFreq += 0.04167;
} else if(fabs(_bw - 62.5) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x40;
fixedRegs[2] = 0x00;
} else if(fabs(_bw - 125.0) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x40;
fixedRegs[2] = 0x00;
} else if(fabs(_bw - 250.0) <= 0.001) {
fixedRegs[0] = 0b0000000;
fixedRegs[1] = 0x40;
fixedRegs[2] = 0x00;
} else if(fabs(_bw - 500.0) <= 0.001) {
fixedRegs[0] = 0b1000000;
fixedRegs[1] = _mod->SPIreadRegister(0x2F);
fixedRegs[2] = _mod->SPIreadRegister(0x30);
} else {
return;
}
// first, go to standby
standby();
// shift the freqency up when receiving, or restore the original when transmitting
if(rx) {
SX127x::setFrequencyRaw(rxFreq);
} else {
SX127x::setFrequencyRaw(_freq);
}
// finally, apply errata fixes
_mod->SPIsetRegValue(0x31, fixedRegs[0], 7, 7);
_mod->SPIsetRegValue(0x2F, fixedRegs[1]);
_mod->SPIsetRegValue(0x30, fixedRegs[2]);
}
#endif