// Copyright (c) Sandeep Mistry. All rights reserved. // Licensed under the MIT license. // Modifications and additions copyright 2024 by Mark Qvist & Jacob Eva // Obviously still under the MIT license. #include "Radio.h" #if PLATFORM == PLATFORM_ESP32 #if defined(ESP32) and !defined(CONFIG_IDF_TARGET_ESP32S3) #include "soc/rtc_wdt.h" #endif #define ISR_VECT IRAM_ATTR #else #define ISR_VECT #endif #define MAX_PKT_LENGTH 255 // SX126x registers #define OP_RF_FREQ_6X 0x86 #define OP_SLEEP_6X 0x84 #define OP_STANDBY_6X 0x80 #define OP_TX_6X 0x83 #define OP_RX_6X 0x82 #define OP_PA_CONFIG_6X 0x95 #define OP_SET_IRQ_FLAGS_6X 0x08 // also provides info such as // preamble detection, etc for // knowing when it's safe to switch // antenna modes #define OP_CLEAR_IRQ_STATUS_6X 0x02 #define OP_GET_IRQ_STATUS_6X 0x12 #define OP_RX_BUFFER_STATUS_6X 0x13 #define OP_PACKET_STATUS_6X 0x14 // get snr & rssi of last packet #define OP_CURRENT_RSSI_6X 0x15 #define OP_MODULATION_PARAMS_6X 0x8B // bw, sf, cr, etc. #define OP_PACKET_PARAMS_6X 0x8C // crc, preamble, payload length, etc. #define OP_STATUS_6X 0xC0 #define OP_TX_PARAMS_6X 0x8E // set dbm, etc #define OP_PACKET_TYPE_6X 0x8A #define OP_BUFFER_BASE_ADDR_6X 0x8F #define OP_READ_REGISTER_6X 0x1D #define OP_WRITE_REGISTER_6X 0x0D #define OP_DIO3_TCXO_CTRL_6X 0x97 #define OP_DIO2_RF_CTRL_6X 0x9D #define OP_CAD_PARAMS 0x88 #define OP_CALIBRATE_6X 0x89 #define OP_RX_TX_FALLBACK_MODE_6X 0x93 #define OP_REGULATOR_MODE_6X 0x96 #define OP_CALIBRATE_IMAGE_6X 0x98 #define MASK_CALIBRATE_ALL 0x7f #define IRQ_TX_DONE_MASK_6X 0x01 #define IRQ_RX_DONE_MASK_6X 0x02 #define IRQ_HEADER_DET_MASK_6X 0x10 #define IRQ_PREAMBLE_DET_MASK_6X 0x04 #define IRQ_PAYLOAD_CRC_ERROR_MASK_6X 0x40 #define IRQ_ALL_MASK_6X 0b0100001111111111 #define MODE_LONG_RANGE_MODE_6X 0x01 #define OP_FIFO_WRITE_6X 0x0E #define OP_FIFO_READ_6X 0x1E #define REG_OCP_6X 0x08E7 #define REG_LNA_6X 0x08AC // no agc in sx1262 #define REG_SYNC_WORD_MSB_6X 0x0740 #define REG_SYNC_WORD_LSB_6X 0x0741 #define REG_PAYLOAD_LENGTH_6X 0x0702 // https://github.com/beegee-tokyo/SX126x-Arduino/blob/master/src/radio/sx126x/sx126x.h#L98 #define REG_RANDOM_GEN_6X 0x0819 #define MODE_TCXO_3_3V_6X 0x07 #define MODE_TCXO_3_0V_6X 0x06 #define MODE_TCXO_2_7V_6X 0x06 #define MODE_TCXO_2_4V_6X 0x06 #define MODE_TCXO_2_2V_6X 0x03 #define MODE_TCXO_1_8V_6X 0x02 #define MODE_TCXO_1_7V_6X 0x01 #define MODE_TCXO_1_6V_6X 0x00 #define MODE_STDBY_RC_6X 0x00 #define MODE_STDBY_XOSC_6X 0x01 #define MODE_FALLBACK_STDBY_RC_6X 0x20 #define MODE_IMPLICIT_HEADER 0x01 #define MODE_EXPLICIT_HEADER 0x00 #define SYNC_WORD_6X 0x1424 #define XTAL_FREQ_6X (double)32000000 #define FREQ_DIV_6X (double)pow(2.0, 25.0) #define FREQ_STEP_6X (double)(XTAL_FREQ_6X / FREQ_DIV_6X) extern int packet_interface; extern RadioInterface* interface_obj[]; // ISRs cannot provide parameters to the functions they call. Since we have // multiple radio objects, we have to read each dio0 pin for each one and see // which one is high. We can then use the index of this pin in the 2D array to // call the correct object. void onDio0Rise() { for (int i = 0; i < INTERFACE_COUNT; i++) { if (digitalRead(interface_pins[i][5]) == HIGH) { packet_interface = i; RadioInterface* obj = interface_obj[i]; obj->handleDio0Rise(); break; } } } sx126x::sx126x(uint8_t index, SPIClass spi, bool tcxo, bool dio2_as_rf_switch, int ss, int sclk, int mosi, int miso, int reset, int dio0, int busy, int rxen) : RadioInterface(index), _spiSettings(8E6, MSBFIRST, SPI_MODE0), _spiModem(spi), _ss(ss), _sclk(sclk), _mosi(mosi), _miso(miso), _reset(reset), _dio0(dio0), _busy(busy), _rxen(rxen), _frequency(0), _txp(0), _sf(0x07), _bw(0x04), _cr(0x01), _ldro(0x00), _packetIndex(0), _implicitHeaderMode(0), _payloadLength(255), _crcMode(1), _fifo_tx_addr_ptr(0), _fifo_rx_addr_ptr(0), _packet({0}), _preinit_done(false), _tcxo(tcxo), _dio2_as_rf_switch(dio2_as_rf_switch) { // overide Stream timeout value setTimeout(0); // TODO, figure out why this has to be done. Using the index to reference the // interface_obj list causes a crash otherwise _index = getIndex(); } bool sx126x::preInit() { pinMode(_ss, OUTPUT); digitalWrite(_ss, HIGH); // todo: check if this change causes issues on any platforms #if MCU_VARIANT == MCU_ESP32 if (_sclk != -1 && _miso != -1 && _mosi != -1 && _ss != -1) { _spiModem.begin(_sclk, _miso, _mosi, _ss); } else { _spiModem.begin(); } #else _spiModem.begin(); #endif // check version (retry for up to 2 seconds) // TODO: Actually read version registers, not syncwords long start = millis(); uint8_t syncmsb; uint8_t synclsb; while (((millis() - start) < 2000) && (millis() >= start)) { syncmsb = readRegister(REG_SYNC_WORD_MSB_6X); synclsb = readRegister(REG_SYNC_WORD_LSB_6X); if ( uint16_t(syncmsb << 8 | synclsb) == 0x1424 || uint16_t(syncmsb << 8 | synclsb) == 0x4434) { break; } delay(100); } if ( uint16_t(syncmsb << 8 | synclsb) != 0x1424 && uint16_t(syncmsb << 8 | synclsb) != 0x4434) { return false; } _preinit_done = true; return true; } uint8_t ISR_VECT sx126x::readRegister(uint16_t address) { return singleTransfer(OP_READ_REGISTER_6X, address, 0x00); } void sx126x::writeRegister(uint16_t address, uint8_t value) { singleTransfer(OP_WRITE_REGISTER_6X, address, value); } uint8_t ISR_VECT sx126x::singleTransfer(uint8_t opcode, uint16_t address, uint8_t value) { waitOnBusy(); uint8_t response; digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); _spiModem.transfer((address & 0xFF00) >> 8); _spiModem.transfer(address & 0x00FF); if (opcode == OP_READ_REGISTER_6X) { _spiModem.transfer(0x00); } response = _spiModem.transfer(value); _spiModem.endTransaction(); digitalWrite(_ss, HIGH); return response; } void sx126x::rxAntEnable() { if (_rxen != -1) { digitalWrite(_rxen, HIGH); } } void sx126x::loraMode() { // enable lora mode on the SX1262 chip uint8_t mode = MODE_LONG_RANGE_MODE_6X; executeOpcode(OP_PACKET_TYPE_6X, &mode, 1); } void sx126x::waitOnBusy() { unsigned long time = millis(); while (digitalRead(_busy) == HIGH) { if (millis() >= (time + 100)) { break; } // do nothing } } void sx126x::executeOpcode(uint8_t opcode, uint8_t *buffer, uint8_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); for (int i = 0; i < size; i++) { _spiModem.transfer(buffer[i]); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx126x::executeOpcodeRead(uint8_t opcode, uint8_t *buffer, uint8_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); _spiModem.transfer(0x00); for (int i = 0; i < size; i++) { buffer[i] = _spiModem.transfer(0x00); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx126x::writeBuffer(const uint8_t* buffer, size_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(OP_FIFO_WRITE_6X); _spiModem.transfer(_fifo_tx_addr_ptr); for (int i = 0; i < size; i++) { _spiModem.transfer(buffer[i]); _fifo_tx_addr_ptr++; } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx126x::readBuffer(uint8_t* buffer, size_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(OP_FIFO_READ_6X); _spiModem.transfer(_fifo_rx_addr_ptr); _spiModem.transfer(0x00); for (int i = 0; i < size; i++) { buffer[i] = _spiModem.transfer(0x00); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx126x::setModulationParams(uint8_t sf, uint8_t bw, uint8_t cr, int ldro) { // because there is no access to these registers on the sx1262, we have // to set all these parameters at once or not at all. uint8_t buf[8]; buf[0] = sf; buf[1] = bw; buf[2] = cr; // low data rate toggle buf[3] = ldro; // unused params in LoRa mode buf[4] = 0x00; buf[5] = 0x00; buf[6] = 0x00; buf[7] = 0x00; executeOpcode(OP_MODULATION_PARAMS_6X, buf, 8); } void sx126x::setPacketParams(uint32_t preamble, uint8_t headermode, uint8_t length, uint8_t crc) { // because there is no access to these registers on the sx1262, we have // to set all these parameters at once or not at all. uint8_t buf[9]; buf[0] = uint8_t((preamble & 0xFF00) >> 8); buf[1] = uint8_t((preamble & 0x00FF)); buf[2] = headermode; buf[3] = length; buf[4] = crc; // standard IQ setting (no inversion) buf[5] = 0x00; // unused params buf[6] = 0x00; buf[7] = 0x00; buf[8] = 0x00; executeOpcode(OP_PACKET_PARAMS_6X, buf, 9); } void sx126x::reset(void) { if (_reset != -1) { pinMode(_reset, OUTPUT); // perform reset digitalWrite(_reset, LOW); delay(10); digitalWrite(_reset, HIGH); delay(10); } } void sx126x::calibrate(void) { // Put in STDBY_RC mode before calibration uint8_t mode_byte = MODE_STDBY_RC_6X; executeOpcode(OP_STANDBY_6X, &mode_byte, 1); // calibrate RC64k, RC13M, PLL, ADC and image uint8_t calibrate = MASK_CALIBRATE_ALL; executeOpcode(OP_CALIBRATE_6X, &calibrate, 1); delay(5); waitOnBusy(); } void sx126x::calibrate_image(uint32_t frequency) { uint8_t image_freq[2] = {0}; if (frequency >= 430E6 && frequency <= 440E6) { image_freq[0] = 0x6B; image_freq[1] = 0x6F; } else if (frequency >= 470E6 && frequency <= 510E6) { image_freq[0] = 0x75; image_freq[1] = 0x81; } else if (frequency >= 779E6 && frequency <= 787E6) { image_freq[0] = 0xC1; image_freq[1] = 0xC5; } else if (frequency >= 863E6 && frequency <= 870E6) { image_freq[0] = 0xD7; image_freq[1] = 0xDB; } else if (frequency >= 902E6 && frequency <= 928E6) { image_freq[0] = 0xE1; image_freq[1] = 0xE9; } executeOpcode(OP_CALIBRATE_IMAGE_6X, image_freq, 2); waitOnBusy(); } int sx126x::begin() { reset(); if (_busy != -1) { pinMode(_busy, INPUT); } if (!_preinit_done) { if (!preInit()) { return false; } } if (_rxen != -1) { pinMode(_rxen, OUTPUT); } calibrate(); calibrate_image(_frequency); enableTCXO(); loraMode(); standby(); // Set sync word setSyncWord(SYNC_WORD_6X); if (_dio2_as_rf_switch) { // enable dio2 rf switch uint8_t byte = 0x01; executeOpcode(OP_DIO2_RF_CTRL_6X, &byte, 1); } rxAntEnable(); setFrequency(_frequency); setTxPower(_txp); enableCrc(); // set LNA boost writeRegister(REG_LNA_6X, 0x96); // set base addresses uint8_t basebuf[2] = {0}; executeOpcode(OP_BUFFER_BASE_ADDR_6X, basebuf, 2); setModulationParams(_sf, _bw, _cr, _ldro); setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); _radio_online = true; return 1; } void sx126x::end() { // put in sleep mode sleep(); // stop SPI _spiModem.end(); _bitrate = 0; _radio_online = false; _preinit_done = false; } int sx126x::beginPacket(int implicitHeader) { standby(); if (implicitHeader) { implicitHeaderMode(); } else { explicitHeaderMode(); } _payloadLength = 0; _fifo_tx_addr_ptr = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); return 1; } int sx126x::endPacket() { setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); // put in single TX mode uint8_t timeout[3] = {0}; executeOpcode(OP_TX_6X, timeout, 3); uint8_t buf[2]; buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2); // wait for TX done while ((buf[1] & IRQ_TX_DONE_MASK_6X) == 0) { buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2); yield(); } // clear IRQ's uint8_t mask[2]; mask[0] = 0x00; mask[1] = IRQ_TX_DONE_MASK_6X; executeOpcode(OP_CLEAR_IRQ_STATUS_6X, mask, 2); return 1; } uint8_t sx126x::modemStatus() { // imitate the register status from the sx1276 / 78 uint8_t buf[2] = {0}; executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2); uint8_t clearbuf[2] = {0}; uint8_t byte = 0x00; if ((buf[1] & IRQ_PREAMBLE_DET_MASK_6X) != 0) { byte = byte | 0x01 | 0x04; // clear register after reading clearbuf[1] = IRQ_PREAMBLE_DET_MASK_6X; } if ((buf[1] & IRQ_HEADER_DET_MASK_6X) != 0) { byte = byte | 0x02 | 0x04; } executeOpcode(OP_CLEAR_IRQ_STATUS_6X, clearbuf, 2); return byte; } uint8_t sx126x::currentRssiRaw() { uint8_t byte = 0; executeOpcodeRead(OP_CURRENT_RSSI_6X, &byte, 1); return byte; } int ISR_VECT sx126x::currentRssi() { uint8_t byte = 0; executeOpcodeRead(OP_CURRENT_RSSI_6X, &byte, 1); int rssi = -(int(byte)) / 2; return rssi; } uint8_t sx126x::packetRssiRaw() { uint8_t buf[3] = {0}; executeOpcodeRead(OP_PACKET_STATUS_6X, buf, 3); return buf[2]; } int ISR_VECT sx126x::packetRssi() { // may need more calculations here uint8_t buf[3] = {0}; executeOpcodeRead(OP_PACKET_STATUS_6X, buf, 3); int pkt_rssi = -buf[0] / 2; return pkt_rssi; } uint8_t ISR_VECT sx126x::packetSnrRaw() { uint8_t buf[3] = {0}; executeOpcodeRead(OP_PACKET_STATUS_6X, buf, 3); return buf[1]; } float ISR_VECT sx126x::packetSnr() { uint8_t buf[3] = {0}; executeOpcodeRead(OP_PACKET_STATUS_6X, buf, 3); return float(buf[1]) * 0.25; } long sx126x::packetFrequencyError() { // todo: implement this, no idea how to check it on the sx1262 const float fError = 0.0; return static_cast(fError); } size_t sx126x::write(uint8_t byte) { return write(&byte, sizeof(byte)); } size_t sx126x::write(const uint8_t *buffer, size_t size) { if ((_payloadLength + size) > MAX_PKT_LENGTH) { size = MAX_PKT_LENGTH - _payloadLength; } // write data writeBuffer(buffer, size); _payloadLength = _payloadLength + size; return size; } int ISR_VECT sx126x::available() { uint8_t buf[2] = {0}; executeOpcodeRead(OP_RX_BUFFER_STATUS_6X, buf, 2); return buf[0] - _packetIndex; } int ISR_VECT sx126x::read() { if (!available()) { return -1; } // if received new packet if (_packetIndex == 0) { uint8_t rxbuf[2] = {0}; executeOpcodeRead(OP_RX_BUFFER_STATUS_6X, rxbuf, 2); int size = rxbuf[0]; _fifo_rx_addr_ptr = rxbuf[1]; readBuffer(_packet, size); } uint8_t byte = _packet[_packetIndex]; _packetIndex++; return byte; } int sx126x::peek() { if (!available()) { return -1; } // if received new packet if (_packetIndex == 0) { uint8_t rxbuf[2] = {0}; executeOpcodeRead(OP_RX_BUFFER_STATUS_6X, rxbuf, 2); int size = rxbuf[0]; _fifo_rx_addr_ptr = rxbuf[1]; readBuffer(_packet, size); } uint8_t b = _packet[_packetIndex]; return b; } void sx126x::flush() { } void sx126x::onReceive(void(*callback)(uint8_t, int)) { _onReceive = callback; if (callback) { pinMode(_dio0, INPUT); // set preamble and header detection irqs, plus dio0 mask uint8_t buf[8]; // set irq masks, enable all buf[0] = 0xFF; buf[1] = 0xFF; // set dio0 masks buf[2] = 0x00; buf[3] = IRQ_RX_DONE_MASK_6X; // set dio1 masks buf[4] = 0x00; buf[5] = 0x00; // set dio2 masks buf[6] = 0x00; buf[7] = 0x00; executeOpcode(OP_SET_IRQ_FLAGS_6X, buf, 8); #ifdef SPI_HAS_NOTUSINGINTERRUPT _spiModem.usingInterrupt(digitalPinToInterrupt(_dio0)); #endif // make function available extern void onDio0Rise(); attachInterrupt(digitalPinToInterrupt(_dio0), onDio0Rise, RISING); } else { detachInterrupt(digitalPinToInterrupt(_dio0)); #ifdef SPI_HAS_NOTUSINGINTERRUPT _spiModem.notUsingInterrupt(digitalPinToInterrupt(_dio0)); #endif } } void sx126x::receive(int size) { if (size > 0) { implicitHeaderMode(); // tell radio payload length _payloadLength = size; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } else { explicitHeaderMode(); } if (_rxen != -1) { rxAntEnable(); } uint8_t mode[3] = {0xFF, 0xFF, 0xFF}; // continuous mode executeOpcode(OP_RX_6X, mode, 3); } void sx126x::standby() { uint8_t byte; if (_tcxo) { // STDBY_XOSC byte = MODE_STDBY_XOSC_6X; } else { // STDBY_RC byte = MODE_STDBY_RC_6X; } executeOpcode(OP_STANDBY_6X, &byte, 1); } void sx126x::sleep() { uint8_t byte = 0x00; executeOpcode(OP_SLEEP_6X, &byte, 1); } void sx126x::enableTCXO() { if (_tcxo) { #if BOARD_MODEL == BOARD_RAK4631 || BOARD_MODEL == BOARD_HELTEC32_V3 uint8_t buf[4] = {MODE_TCXO_3_3V_6X, 0x00, 0x00, 0xFF}; #elif BOARD_MODEL == BOARD_TBEAM uint8_t buf[4] = {MODE_TCXO_1_8V_6X, 0x00, 0x00, 0xFF}; #elif BOARD_MODEL == BOARD_RNODE_NG_22 uint8_t buf[4] = {MODE_TCXO_1_8V_6X, 0x00, 0x00, 0xFF}; #else uint8_t buf[4] = {0}; #endif executeOpcode(OP_DIO3_TCXO_CTRL_6X, buf, 4); } } // TODO: Once enabled, SX1262 needs a complete reset to disable TCXO void sx126x::disableTCXO() { } void sx126x::setTxPower(int level, int outputPin) { // currently no low power mode for SX1262 implemented, assuming PA boost // WORKAROUND - Better Resistance of the SX1262 Tx to Antenna Mismatch, see DS_SX1261-2_V1.2 datasheet chapter 15.2 // RegTxClampConfig = @address 0x08D8 writeRegister(0x08D8, readRegister(0x08D8) | (0x0F << 1)); uint8_t pa_buf[4]; pa_buf[0] = 0x04; // PADutyCycle needs to be 0x04 to achieve 22dBm output, but can be lowered for better efficiency at lower outputs pa_buf[1] = 0x07; // HPMax at 0x07 is maximum supported for SX1262 pa_buf[2] = 0x00; // DeviceSel 0x00 for SX1262 (0x01 for SX1261) pa_buf[3] = 0x01; // PALut always 0x01 (reserved according to datasheet) executeOpcode(OP_PA_CONFIG_6X, pa_buf, 4); // set pa_config for high power if (level > 22) { level = 22; } else if (level < -9) { level = -9; } _txp = level; writeRegister(REG_OCP_6X, 0x38); // 160mA limit, overcurrent protection uint8_t tx_buf[2]; tx_buf[0] = level; tx_buf[1] = 0x02; // PA ramping time - 40 microseconds executeOpcode(OP_TX_PARAMS_6X, tx_buf, 2); } uint8_t sx126x::getTxPower() { return _txp; } void sx126x::setFrequency(uint32_t frequency) { _frequency = frequency; uint8_t buf[4]; uint32_t freq = (uint32_t)((double)frequency / (double)FREQ_STEP_6X); buf[0] = ((freq >> 24) & 0xFF); buf[1] = ((freq >> 16) & 0xFF); buf[2] = ((freq >> 8) & 0xFF); buf[3] = (freq & 0xFF); executeOpcode(OP_RF_FREQ_6X, buf, 4); } uint32_t sx126x::getFrequency() { // we can't read the frequency on the sx1262 / 80 uint32_t frequency = _frequency; return frequency; } void sx126x::setSpreadingFactor(int sf) { if (sf < 5) { sf = 5; } else if (sf > 12) { sf = 12; } _sf = sf; handleLowDataRate(); setModulationParams(sf, _bw, _cr, _ldro); } uint8_t sx126x::getSpreadingFactor() { return _sf; } uint32_t sx126x::getSignalBandwidth() { int bw = _bw; switch (bw) { case 0x00: return 7.8E3; case 0x01: return 15.6E3; case 0x02: return 31.25E3; case 0x03: return 62.5E3; case 0x04: return 125E3; case 0x05: return 250E3; case 0x06: return 500E3; case 0x08: return 10.4E3; case 0x09: return 20.8E3; case 0x0A: return 41.7E3; } return 0; } void sx126x::handleLowDataRate(){ if ( long( (1<<_sf) / (getSignalBandwidth()/1000)) > 16) { _ldro = 0x01; } else { _ldro = 0x00; } } void sx126x::optimizeModemSensitivity(){ // todo: check if there's anything the sx1262 can do here } void sx126x::setSignalBandwidth(uint32_t sbw) { if (sbw <= 7.8E3) { _bw = 0x00; } else if (sbw <= 10.4E3) { _bw = 0x08; } else if (sbw <= 15.6E3) { _bw = 0x01; } else if (sbw <= 20.8E3) { _bw = 0x09; } else if (sbw <= 31.25E3) { _bw = 0x02; } else if (sbw <= 41.7E3) { _bw = 0x0A; } else if (sbw <= 62.5E3) { _bw = 0x03; } else if (sbw <= 125E3) { _bw = 0x04; } else if (sbw <= 250E3) { _bw = 0x05; } else /*if (sbw <= 250E3)*/ { _bw = 0x06; } handleLowDataRate(); setModulationParams(_sf, _bw, _cr, _ldro); optimizeModemSensitivity(); } void sx126x::setCodingRate4(int denominator) { if (denominator < 5) { denominator = 5; } else if (denominator > 8) { denominator = 8; } int cr = denominator - 4; _cr = cr; setModulationParams(_sf, _bw, cr, _ldro); } uint8_t sx126x::getCodingRate4() { return _cr + 4; } void sx126x::setPreambleLength(long length) { _preambleLength = length; setPacketParams(length, _implicitHeaderMode, _payloadLength, _crcMode); } void sx126x::setSyncWord(uint16_t sw) { // TODO: Fix // writeRegister(REG_SYNC_WORD_MSB_6X, (sw & 0xFF00) >> 8); // writeRegister(REG_SYNC_WORD_LSB_6X, sw & 0x00FF); writeRegister(REG_SYNC_WORD_MSB_6X, 0x14); writeRegister(REG_SYNC_WORD_LSB_6X, 0x24); } void sx126x::enableCrc() { _crcMode = 1; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void sx126x::disableCrc() { _crcMode = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } byte sx126x::random() { return readRegister(REG_RANDOM_GEN_6X); } void sx126x::setSPIFrequency(uint32_t frequency) { _spiSettings = SPISettings(frequency, MSBFIRST, SPI_MODE0); } void sx126x::dumpRegisters(Stream& out) { for (int i = 0; i < 128; i++) { out.print("0x"); out.print(i, HEX); out.print(": 0x"); out.println(readRegister(i), HEX); } } void sx126x::explicitHeaderMode() { _implicitHeaderMode = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void sx126x::implicitHeaderMode() { _implicitHeaderMode = 1; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void ISR_VECT sx126x::handleDio0Rise() { uint8_t buf[2]; buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_6X, buf, 2); executeOpcode(OP_CLEAR_IRQ_STATUS_6X, buf, 2); if ((buf[1] & IRQ_PAYLOAD_CRC_ERROR_MASK_6X) == 0) { // received a packet _packetIndex = 0; // read packet length uint8_t rxbuf[2] = {0}; executeOpcodeRead(OP_RX_BUFFER_STATUS_6X, rxbuf, 2); int packetLength = rxbuf[0]; if (_onReceive) { _onReceive(_index, packetLength); } } // else { // Serial.println("CRCE"); // Serial.println(buf[0]); // Serial.println(buf[1]); // } } void sx126x::updateBitrate() { if (_radio_online) { _lora_symbol_rate = (float)getSignalBandwidth()/(float)(pow(2, _sf)); _lora_symbol_time_ms = (1.0/_lora_symbol_rate)*1000.0; _bitrate = (uint32_t)(_sf * ( (4.0/(float)(_cr+4)) / ((float)(pow(2, _sf))/((float)getSignalBandwidth()/1000.0)) ) * 1000.0); _lora_us_per_byte = 1000000.0/((float)_bitrate/8.0); //_csma_slot_ms = _lora_symbol_time_ms*10; float target_preamble_symbols = (LORA_PREAMBLE_TARGET_MS/_lora_symbol_time_ms)-LORA_PREAMBLE_SYMBOLS_HW; if (target_preamble_symbols < LORA_PREAMBLE_SYMBOLS_MIN) { target_preamble_symbols = LORA_PREAMBLE_SYMBOLS_MIN; } else { target_preamble_symbols = ceil(target_preamble_symbols); } _preambleLength = (long)target_preamble_symbols; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } else { _bitrate = 0; } } // SX127x registers #define REG_FIFO_7X 0x00 #define REG_OP_MODE_7X 0x01 #define REG_FRF_MSB_7X 0x06 #define REG_FRF_MID_7X 0x07 #define REG_FRF_LSB_7X 0x08 #define REG_PA_CONFIG_7X 0x09 #define REG_OCP_7X 0x0b #define REG_LNA_7X 0x0c #define REG_FIFO_ADDR_PTR_7X 0x0d #define REG_FIFO_TX_BASE_ADDR_7X 0x0e #define REG_FIFO_RX_BASE_ADDR_7X 0x0f #define REG_FIFO_RX_CURRENT_ADDR_7X 0x10 #define REG_IRQ_FLAGS_7X 0x12 #define REG_RX_NB_BYTES_7X 0x13 #define REG_MODEM_STAT_7X 0x18 #define REG_PKT_SNR_VALUE_7X 0x19 #define REG_PKT_RSSI_VALUE_7X 0x1a #define REG_RSSI_VALUE_7X 0x1b #define REG_MODEM_CONFIG_1_7X 0x1d #define REG_MODEM_CONFIG_2_7X 0x1e #define REG_PREAMBLE_MSB_7X 0x20 #define REG_PREAMBLE_LSB_7X 0x21 #define REG_PAYLOAD_LENGTH_7X 0x22 #define REG_MODEM_CONFIG_3_7X 0x26 #define REG_FREQ_ERROR_MSB_7X 0x28 #define REG_FREQ_ERROR_MID_7X 0x29 #define REG_FREQ_ERROR_LSB_7X 0x2a #define REG_RSSI_WIDEBAND_7X 0x2c #define REG_DETECTION_OPTIMIZE_7X 0x31 #define REG_HIGH_BW_OPTIMIZE_1_7X 0x36 #define REG_DETECTION_THRESHOLD_7X 0x37 #define REG_SYNC_WORD_7X 0x39 #define REG_HIGH_BW_OPTIMIZE_2_7X 0x3a #define REG_DIO_MAPPING_1_7X 0x40 #define REG_VERSION_7X 0x42 #define REG_TCXO_7X 0x4b #define REG_PA_DAC_7X 0x4d // Modes #define MODE_LONG_RANGE_MODE_7X 0x80 #define MODE_SLEEP_7X 0x00 #define MODE_STDBY_7X 0x01 #define MODE_TX_7X 0x03 #define MODE_RX_CONTINUOUS_7X 0x05 #define MODE_RX_SINGLE_7X 0x06 // PA config #define PA_BOOST_7X 0x80 // IRQ masks #define IRQ_TX_DONE_MASK_7X 0x08 #define IRQ_RX_DONE_MASK_7X 0x40 #define IRQ_PAYLOAD_CRC_ERROR_MASK_7X 0x20 #define SYNC_WORD_7X 0x12 sx127x::sx127x(uint8_t index, SPIClass spi, int ss, int sclk, int mosi, int miso, int reset, int dio0, int busy) : RadioInterface(index), _spiSettings(8E6, MSBFIRST, SPI_MODE0), _spiModem(spi), _ss(ss), _sclk(sclk), _mosi(mosi), _miso(miso), _reset(reset), _dio0(dio0), _busy(busy), _frequency(0), _packetIndex(0), _preinit_done(false) { setTimeout(0); // TODO, figure out why this has to be done. Using the index to reference the // interface_obj list causes a crash otherwise _index = getIndex(); } void sx127x::setSPIFrequency(uint32_t frequency) { _spiSettings = SPISettings(frequency, MSBFIRST, SPI_MODE0); } uint8_t ISR_VECT sx127x::readRegister(uint8_t address) { return singleTransfer(address & 0x7f, 0x00); } void sx127x::writeRegister(uint8_t address, uint8_t value) { singleTransfer(address | 0x80, value); } void sx127x::standby() { writeRegister(REG_OP_MODE_7X, MODE_LONG_RANGE_MODE_7X | MODE_STDBY_7X); } void sx127x::sleep() { writeRegister(REG_OP_MODE_7X, MODE_LONG_RANGE_MODE_7X | MODE_SLEEP_7X); } uint8_t sx127x::modemStatus() { return readRegister(REG_MODEM_STAT_7X); } void sx127x::setSyncWord(uint8_t sw) { writeRegister(REG_SYNC_WORD_7X, sw); } void sx127x::enableCrc() { writeRegister(REG_MODEM_CONFIG_2_7X, readRegister(REG_MODEM_CONFIG_2_7X) | 0x04); } void sx127x::disableCrc() { writeRegister(REG_MODEM_CONFIG_2_7X, readRegister(REG_MODEM_CONFIG_2_7X) & 0xfb); } void sx127x::enableTCXO() { uint8_t tcxo_reg = readRegister(REG_TCXO_7X); writeRegister(REG_TCXO_7X, tcxo_reg | 0x10); } void sx127x::disableTCXO() { uint8_t tcxo_reg = readRegister(REG_TCXO_7X); writeRegister(REG_TCXO_7X, tcxo_reg & 0xEF); } void sx127x::explicitHeaderMode() { _implicitHeaderMode = 0; writeRegister(REG_MODEM_CONFIG_1_7X, readRegister(REG_MODEM_CONFIG_1_7X) & 0xfe); } void sx127x::implicitHeaderMode() { _implicitHeaderMode = 1; writeRegister(REG_MODEM_CONFIG_1_7X, readRegister(REG_MODEM_CONFIG_1_7X) | 0x01); } byte sx127x::random() { return readRegister(REG_RSSI_WIDEBAND_7X); } void sx127x::flush() { } bool sx127x::preInit() { pinMode(_ss, OUTPUT); digitalWrite(_ss, HIGH); // todo: check if this change causes issues on any platforms #if MCU_VARIANT == MCU_ESP32 if (_sclk != -1 && _miso != -1 && _mosi != -1 && _ss != -1) { _spiModem.begin(_sclk, _miso, _mosi, _ss); } else { _spiModem.begin(); } #else _spiModem.begin(); #endif // Check modem version uint8_t version; long start = millis(); while (((millis() - start) < 500) && (millis() >= start)) { version = readRegister(REG_VERSION_7X); if (version == 0x12) { break; } delay(100); } if (version != 0x12) { return false; } _preinit_done = true; return true; } uint8_t ISR_VECT sx127x::singleTransfer(uint8_t address, uint8_t value) { uint8_t response; digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(address); response = _spiModem.transfer(value); _spiModem.endTransaction(); digitalWrite(_ss, HIGH); return response; } int sx127x::begin() { if (_reset != -1) { pinMode(_reset, OUTPUT); // Perform reset digitalWrite(_reset, LOW); delay(10); digitalWrite(_reset, HIGH); delay(10); } if (_busy != -1) { pinMode(_busy, INPUT); } if (!_preinit_done) { if (!preInit()) { return false; } } sleep(); setFrequency(_frequency); // set base addresses writeRegister(REG_FIFO_TX_BASE_ADDR_7X, 0); writeRegister(REG_FIFO_RX_BASE_ADDR_7X, 0); // set LNA boost and auto AGC writeRegister(REG_LNA_7X, readRegister(REG_LNA_7X) | 0x03); writeRegister(REG_MODEM_CONFIG_3_7X, 0x04); setSyncWord(SYNC_WORD_7X); enableCrc(); setTxPower(2); standby(); _radio_online = true; return 1; } void sx127x::end() { sleep(); _spiModem.end(); _bitrate = 0; _radio_online = false; _preinit_done = false; } int sx127x::beginPacket(int implicitHeader) { standby(); if (implicitHeader) { implicitHeaderMode(); } else { explicitHeaderMode(); } // Reset FIFO address and payload length writeRegister(REG_FIFO_ADDR_PTR_7X, 0); writeRegister(REG_PAYLOAD_LENGTH_7X, 0); return 1; } int sx127x::endPacket() { // Enter TX mode writeRegister(REG_OP_MODE_7X, MODE_LONG_RANGE_MODE_7X | MODE_TX_7X); // Wait for TX completion while ((readRegister(REG_IRQ_FLAGS_7X) & IRQ_TX_DONE_MASK_7X) == 0) { yield(); } // Clear TX complete IRQ writeRegister(REG_IRQ_FLAGS_7X, IRQ_TX_DONE_MASK_7X); return 1; } uint8_t sx127x::currentRssiRaw() { uint8_t rssi = readRegister(REG_RSSI_VALUE_7X); return rssi; } int ISR_VECT sx127x::currentRssi() { int rssi = (int)readRegister(REG_RSSI_VALUE_7X) - RSSI_OFFSET; if (_frequency < 820E6) rssi -= 7; return rssi; } uint8_t sx127x::packetRssiRaw() { uint8_t pkt_rssi_value = readRegister(REG_PKT_RSSI_VALUE_7X); return pkt_rssi_value; } int ISR_VECT sx127x::packetRssi() { int pkt_rssi = (int)readRegister(REG_PKT_RSSI_VALUE_7X) - RSSI_OFFSET; int pkt_snr = packetSnr(); if (_frequency < 820E6) pkt_rssi -= 7; if (pkt_snr < 0) { pkt_rssi += pkt_snr; } else { // Slope correction is (16/15)*pkt_rssi, // this estimation looses one floating point // operation, and should be precise enough. pkt_rssi = (int)(1.066 * pkt_rssi); } return pkt_rssi; } uint8_t ISR_VECT sx127x::packetSnrRaw() { return readRegister(REG_PKT_SNR_VALUE_7X); } float ISR_VECT sx127x::packetSnr() { return ((int8_t)readRegister(REG_PKT_SNR_VALUE_7X)) * 0.25; } long sx127x::packetFrequencyError() { int32_t freqError = 0; freqError = static_cast(readRegister(REG_FREQ_ERROR_MSB_7X) & B111); freqError <<= 8L; freqError += static_cast(readRegister(REG_FREQ_ERROR_MID_7X)); freqError <<= 8L; freqError += static_cast(readRegister(REG_FREQ_ERROR_LSB_7X)); if (readRegister(REG_FREQ_ERROR_MSB_7X) & B1000) { // Sign bit is on freqError -= 524288; // B1000'0000'0000'0000'0000 } const float fXtal = 32E6; // FXOSC: crystal oscillator (XTAL) frequency (2.5. Chip Specification, p. 14) const float fError = ((static_cast(freqError) * (1L << 24)) / fXtal) * (getSignalBandwidth() / 500000.0f); return static_cast(fError); } size_t sx127x::write(uint8_t byte) { return write(&byte, sizeof(byte)); } size_t sx127x::write(const uint8_t *buffer, size_t size) { int currentLength = readRegister(REG_PAYLOAD_LENGTH_7X); if ((currentLength + size) > MAX_PKT_LENGTH) { size = MAX_PKT_LENGTH - currentLength; } for (size_t i = 0; i < size; i++) { writeRegister(REG_FIFO_7X, buffer[i]); } writeRegister(REG_PAYLOAD_LENGTH_7X, currentLength + size); return size; } int ISR_VECT sx127x::available() { return (readRegister(REG_RX_NB_BYTES_7X) - _packetIndex); } int ISR_VECT sx127x::read() { if (!available()) { return -1; } _packetIndex++; return readRegister(REG_FIFO_7X); } int sx127x::peek() { if (!available()) { return -1; } // Remember current FIFO address, read, and then reset address int currentAddress = readRegister(REG_FIFO_ADDR_PTR_7X); uint8_t b = readRegister(REG_FIFO_7X); writeRegister(REG_FIFO_ADDR_PTR_7X, currentAddress); return b; } void sx127x::onReceive(void(*callback)(uint8_t, int)) { _onReceive = callback; if (callback) { pinMode(_dio0, INPUT); writeRegister(REG_DIO_MAPPING_1_7X, 0x00); #ifdef SPI_HAS_NOTUSINGINTERRUPT _spiModem.usingInterrupt(digitalPinToInterrupt(_dio0)); #endif // make function available extern void onDio0Rise(); attachInterrupt(digitalPinToInterrupt(_dio0), onDio0Rise, RISING); } else { detachInterrupt(digitalPinToInterrupt(_dio0)); #ifdef SPI_HAS_NOTUSINGINTERRUPT _spiModem.notUsingInterrupt(digitalPinToInterrupt(_dio0)); #endif } } void sx127x::receive(int size) { if (size > 0) { implicitHeaderMode(); writeRegister(REG_PAYLOAD_LENGTH_7X, size & 0xff); } else { explicitHeaderMode(); } writeRegister(REG_OP_MODE_7X, MODE_LONG_RANGE_MODE_7X | MODE_RX_CONTINUOUS_7X); } void sx127x::setTxPower(int level, int outputPin) { // Setup according to RFO or PA_BOOST output pin if (PA_OUTPUT_RFO_PIN == outputPin) { if (level < 0) { level = 0; } else if (level > 14) { level = 14; } writeRegister(REG_PA_DAC_7X, 0x84); writeRegister(REG_PA_CONFIG_7X, 0x70 | level); } else { if (level < 2) { level = 2; } else if (level > 17) { level = 17; } writeRegister(REG_PA_DAC_7X, 0x84); writeRegister(REG_PA_CONFIG_7X, PA_BOOST_7X | (level - 2)); } } uint8_t sx127x::getTxPower() { byte txp = readRegister(REG_PA_CONFIG_7X); return txp; } void sx127x::setFrequency(uint32_t frequency) { _frequency = frequency; uint32_t frf = ((uint64_t)frequency << 19) / 32000000; writeRegister(REG_FRF_MSB_7X, (uint8_t)(frf >> 16)); writeRegister(REG_FRF_MID_7X, (uint8_t)(frf >> 8)); writeRegister(REG_FRF_LSB_7X, (uint8_t)(frf >> 0)); optimizeModemSensitivity(); } uint32_t sx127x::getFrequency() { uint8_t msb = readRegister(REG_FRF_MSB_7X); uint8_t mid = readRegister(REG_FRF_MID_7X); uint8_t lsb = readRegister(REG_FRF_LSB_7X); uint32_t frf = ((uint32_t)msb << 16) | ((uint32_t)mid << 8) | (uint32_t)lsb; uint64_t frm = (uint64_t)frf*32000000; uint32_t frequency = (frm >> 19); return frequency; } void sx127x::setSpreadingFactor(int sf) { if (sf < 6) { sf = 6; } else if (sf > 12) { sf = 12; } if (sf == 6) { writeRegister(REG_DETECTION_OPTIMIZE_7X, 0xc5); writeRegister(REG_DETECTION_THRESHOLD_7X, 0x0c); } else { writeRegister(REG_DETECTION_OPTIMIZE_7X, 0xc3); writeRegister(REG_DETECTION_THRESHOLD_7X, 0x0a); } _sf = sf; writeRegister(REG_MODEM_CONFIG_2_7X, (readRegister(REG_MODEM_CONFIG_2_7X) & 0x0f) | ((sf << 4) & 0xf0)); handleLowDataRate(); } uint8_t sx127x::getSpreadingFactor() { return _sf; } uint32_t sx127x::getSignalBandwidth() { byte bw = (readRegister(REG_MODEM_CONFIG_1_7X) >> 4); switch (bw) { case 0: return 7.8E3; case 1: return 10.4E3; case 2: return 15.6E3; case 3: return 20.8E3; case 4: return 31.25E3; case 5: return 41.7E3; case 6: return 62.5E3; case 7: return 125E3; case 8: return 250E3; case 9: return 500E3; } return 0; } void sx127x::setSignalBandwidth(uint32_t sbw) { int bw; if (sbw <= 7.8E3) { bw = 0; } else if (sbw <= 10.4E3) { bw = 1; } else if (sbw <= 15.6E3) { bw = 2; } else if (sbw <= 20.8E3) { bw = 3; } else if (sbw <= 31.25E3) { bw = 4; } else if (sbw <= 41.7E3) { bw = 5; } else if (sbw <= 62.5E3) { bw = 6; } else if (sbw <= 125E3) { bw = 7; } else if (sbw <= 250E3) { bw = 8; } else /*if (sbw <= 250E3)*/ { bw = 9; } writeRegister(REG_MODEM_CONFIG_1_7X, (readRegister(REG_MODEM_CONFIG_1_7X) & 0x0f) | (bw << 4)); handleLowDataRate(); optimizeModemSensitivity(); } void sx127x::setCodingRate4(int denominator) { if (denominator < 5) { denominator = 5; } else if (denominator > 8) { denominator = 8; } int cr = denominator - 4; _cr = cr; writeRegister(REG_MODEM_CONFIG_1_7X, (readRegister(REG_MODEM_CONFIG_1_7X) & 0xf1) | (cr << 1)); } uint8_t sx127x::getCodingRate4() { return _cr + 4; } void sx127x::setPreambleLength(long length) { _preambleLength = length; writeRegister(REG_PREAMBLE_MSB_7X, (uint8_t)(length >> 8)); writeRegister(REG_PREAMBLE_LSB_7X, (uint8_t)(length >> 0)); } void sx127x::handleLowDataRate() { int sf = (readRegister(REG_MODEM_CONFIG_2_7X) >> 4); if ( long( (1< 16) { // Set auto AGC and LowDataRateOptimize writeRegister(REG_MODEM_CONFIG_3_7X, (1<<3)|(1<<2)); } else { // Only set auto AGC writeRegister(REG_MODEM_CONFIG_3_7X, (1<<2)); } } void sx127x::optimizeModemSensitivity() { byte bw = (readRegister(REG_MODEM_CONFIG_1_7X) >> 4); uint32_t freq = getFrequency(); if (bw == 9 && (410E6 <= freq) && (freq <= 525E6)) { writeRegister(REG_HIGH_BW_OPTIMIZE_1_7X, 0x02); writeRegister(REG_HIGH_BW_OPTIMIZE_2_7X, 0x7f); } else if (bw == 9 && (820E6 <= freq) && (freq <= 1020E6)) { writeRegister(REG_HIGH_BW_OPTIMIZE_1_7X, 0x02); writeRegister(REG_HIGH_BW_OPTIMIZE_2_7X, 0x64); } else { writeRegister(REG_HIGH_BW_OPTIMIZE_1_7X, 0x03); } } void ISR_VECT sx127x::handleDio0Rise() { int irqFlags = readRegister(REG_IRQ_FLAGS_7X); // Clear IRQs writeRegister(REG_IRQ_FLAGS_7X, irqFlags); if ((irqFlags & IRQ_PAYLOAD_CRC_ERROR_MASK_7X) == 0) { _packetIndex = 0; int packetLength = _implicitHeaderMode ? readRegister(REG_PAYLOAD_LENGTH_7X) : readRegister(REG_RX_NB_BYTES_7X); writeRegister(REG_FIFO_ADDR_PTR_7X, readRegister(REG_FIFO_RX_CURRENT_ADDR_7X)); if (_onReceive) { _onReceive(_index, packetLength); } writeRegister(REG_FIFO_ADDR_PTR_7X, 0); } } void sx127x::updateBitrate() { if (_radio_online) { _lora_symbol_rate = (float)getSignalBandwidth()/(float)(pow(2, _sf)); _lora_symbol_time_ms = (1.0/_lora_symbol_rate)*1000.0; _bitrate = (uint32_t)(_sf * ( (4.0/(float)(_cr+4)) / ((float)(pow(2, _sf))/((float)getSignalBandwidth()/1000.0)) ) * 1000.0); _lora_us_per_byte = 1000000.0/((float)_bitrate/8.0); //_csma_slot_ms = _lora_symbol_time_ms*10; float target_preamble_symbols = (LORA_PREAMBLE_TARGET_MS/_lora_symbol_time_ms)-LORA_PREAMBLE_SYMBOLS_HW; if (target_preamble_symbols < LORA_PREAMBLE_SYMBOLS_MIN) { target_preamble_symbols = LORA_PREAMBLE_SYMBOLS_MIN; } else { target_preamble_symbols = ceil(target_preamble_symbols); } _preambleLength = (long)target_preamble_symbols; } else { _bitrate = 0; } } // SX128x registers #define OP_RF_FREQ_8X 0x86 #define OP_SLEEP_8X 0x84 #define OP_STANDBY_8X 0x80 #define OP_TX_8X 0x83 #define OP_RX_8X 0x82 #define OP_SET_IRQ_FLAGS_8X 0x8D // also provides info such as // preamble detection, etc for // knowing when it's safe to switch // antenna modes #define OP_CLEAR_IRQ_STATUS_8X 0x97 #define OP_GET_IRQ_STATUS_8X 0x15 #define OP_RX_BUFFER_STATUS_8X 0x17 #define OP_PACKET_STATUS_8X 0x1D // get snr & rssi of last packet #define OP_CURRENT_RSSI_8X 0x1F #define OP_MODULATION_PARAMS_8X 0x8B // bw, sf, cr, etc. #define OP_PACKET_PARAMS_8X 0x8C // crc, preamble, payload length, etc. #define OP_STATUS_8X 0xC0 #define OP_TX_PARAMS_8X 0x8E // set dbm, etc #define OP_PACKET_TYPE_8X 0x8A #define OP_BUFFER_BASE_ADDR_8X 0x8F #define OP_READ_REGISTER_8X 0x19 #define OP_WRITE_REGISTER_8X 0x18 #define IRQ_TX_DONE_MASK_8X 0x01 #define IRQ_RX_DONE_MASK_8X 0x02 #define IRQ_HEADER_DET_MASK_8X 0x10 #define IRQ_HEADER_ERROR_MASK_8X 0x20 #define IRQ_PAYLOAD_CRC_ERROR_MASK_8X 0x40 #define MODE_LONG_RANGE_MODE_8X 0x01 #define OP_FIFO_WRITE_8X 0x1A #define OP_FIFO_READ_8X 0x1B #define IRQ_PREAMBLE_DET_MASK_8X 0x80 #define REG_PACKET_SIZE 0x901 #define REG_FIRM_VER_MSB 0x154 #define REG_FIRM_VER_LSB 0x153 #define XTAL_FREQ_8X (double)52000000 #define FREQ_DIV_8X (double)pow(2.0, 18.0) #define FREQ_STEP_8X (double)(XTAL_FREQ_8X / FREQ_DIV_8X) sx128x::sx128x(uint8_t index, SPIClass spi, bool tcxo, int ss, int sclk, int mosi, int miso, int reset, int dio0, int busy, int rxen, int txen) : RadioInterface(index), _spiSettings(8E6, MSBFIRST, SPI_MODE0), _spiModem(spi), _ss(ss), _sclk(sclk), _mosi(mosi), _miso(miso), _reset(reset), _dio0(dio0), _busy(busy), _rxen(rxen), _txen(txen), _frequency(0), _txp(0), _sf(0x50), _bw(0x34), _cr(0x01), _packetIndex(0), _implicitHeaderMode(0), _payloadLength(255), _crcMode(0), _fifo_tx_addr_ptr(0), _fifo_rx_addr_ptr(0), _packet({0}), _rxPacketLength(0), _preinit_done(false), _tcxo(tcxo) { // overide Stream timeout value setTimeout(0); // TODO, figure out why this has to be done. Using the index to reference the // interface_obj list causes a crash otherwise _index = getIndex(); } bool sx128x::preInit() { // setup pins pinMode(_ss, OUTPUT); // set SS high digitalWrite(_ss, HIGH); // todo: check if this change causes issues on any platforms #if MCU_VARIANT == MCU_ESP32 if (_sclk != -1 && _miso != -1 && _mosi != -1 && _ss != -1) { _spiModem.begin(_sclk, _miso, _mosi, _ss); } else { _spiModem.begin(); } #else _spiModem.begin(); #endif // check version (retry for up to 2 seconds) long start = millis(); uint8_t version_msb; uint8_t version_lsb; while (((millis() - start) < 2000) && (millis() >= start)) { version_msb = readRegister(REG_FIRM_VER_MSB); version_lsb = readRegister(REG_FIRM_VER_LSB); if ((version_msb == 0xB7 && version_lsb == 0xA9) || (version_msb == 0xB5 && version_lsb == 0xA9)) { break; } delay(100); } if ((version_msb != 0xB7 || version_lsb != 0xA9) && (version_msb != 0xB5 || version_lsb != 0xA9)) { return false; } _preinit_done = true; return true; } uint8_t ISR_VECT sx128x::readRegister(uint16_t address) { return singleTransfer(OP_READ_REGISTER_8X, address, 0x00); } void sx128x::writeRegister(uint16_t address, uint8_t value) { singleTransfer(OP_WRITE_REGISTER_8X, address, value); } uint8_t ISR_VECT sx128x::singleTransfer(uint8_t opcode, uint16_t address, uint8_t value) { waitOnBusy(); uint8_t response; digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); _spiModem.transfer((address & 0xFF00) >> 8); _spiModem.transfer(address & 0x00FF); if (opcode == OP_READ_REGISTER_8X) { _spiModem.transfer(0x00); } response = _spiModem.transfer(value); _spiModem.endTransaction(); digitalWrite(_ss, HIGH); return response; } void sx128x::rxAntEnable() { if (_txen != -1) { digitalWrite(_txen, LOW); } if (_rxen != -1) { digitalWrite(_rxen, HIGH); } } void sx128x::txAntEnable() { if (_txen != -1) { digitalWrite(_txen, HIGH); } if (_rxen != -1) { digitalWrite(_rxen, LOW); } } void sx128x::loraMode() { // enable lora mode on the SX1262 chip uint8_t mode = MODE_LONG_RANGE_MODE_8X; executeOpcode(OP_PACKET_TYPE_8X, &mode, 1); } void sx128x::waitOnBusy() { unsigned long time = millis(); while (digitalRead(_busy) == HIGH) { if (millis() >= (time + 100)) { break; } // do nothing } } void sx128x::executeOpcode(uint8_t opcode, uint8_t *buffer, uint8_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); for (int i = 0; i < size; i++) { _spiModem.transfer(buffer[i]); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx128x::executeOpcodeRead(uint8_t opcode, uint8_t *buffer, uint8_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(opcode); _spiModem.transfer(0x00); for (int i = 0; i < size; i++) { buffer[i] = _spiModem.transfer(0x00); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx128x::writeBuffer(const uint8_t* buffer, size_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(OP_FIFO_WRITE_8X); _spiModem.transfer(_fifo_tx_addr_ptr); for (int i = 0; i < size; i++) { _spiModem.transfer(buffer[i]); _fifo_tx_addr_ptr++; } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx128x::readBuffer(uint8_t* buffer, size_t size) { waitOnBusy(); digitalWrite(_ss, LOW); _spiModem.beginTransaction(_spiSettings); _spiModem.transfer(OP_FIFO_READ_8X); _spiModem.transfer(_fifo_rx_addr_ptr); _spiModem.transfer(0x00); for (int i = 0; i < size; i++) { buffer[i] = _spiModem.transfer(0x00); } _spiModem.endTransaction(); digitalWrite(_ss, HIGH); } void sx128x::setModulationParams(uint8_t sf, uint8_t bw, uint8_t cr) { // because there is no access to these registers on the sx1280, we have // to set all these parameters at once or not at all. uint8_t buf[3]; buf[0] = sf << 4; buf[1] = bw; buf[2] = cr; executeOpcode(OP_MODULATION_PARAMS_8X, buf, 3); if (sf <= 6) { writeRegister(0x925, 0x1E); } else if (sf <= 8) { writeRegister(0x925, 0x37); } else if (sf >= 9) { writeRegister(0x925, 0x32); } writeRegister(0x093C, 0x1); } void sx128x::setPacketParams(uint32_t preamble, uint8_t headermode, uint8_t length, uint8_t crc) { // because there is no access to these registers on the sx1280, we have // to set all these parameters at once or not at all. uint8_t buf[7]; // calculate exponent and mantissa values for modem uint8_t e = 1; uint8_t m = 1; uint32_t preamblelen; for (e <= 15; e++;) { for (m <= 15; m++;) { preamblelen = m * (uint32_t(1) << e); if (preamblelen >= preamble) break; } if (preamblelen >= preamble) break; } buf[0] = (e << 4) | m; buf[1] = headermode; buf[2] = length; buf[3] = crc; // standard IQ setting (no inversion) buf[4] = 0x40; // unused params buf[5] = 0x00; buf[6] = 0x00; executeOpcode(OP_PACKET_PARAMS_8X, buf, 7); } int sx128x::begin() { if (_reset != -1) { pinMode(_reset, OUTPUT); // perform reset digitalWrite(_reset, LOW); delay(10); digitalWrite(_reset, HIGH); delay(10); } if (_rxen != -1) { pinMode(_rxen, OUTPUT); } if (_txen != -1) { pinMode(_txen, OUTPUT); } if (_busy != -1) { pinMode(_busy, INPUT); } if (!_preinit_done) { if (!preInit()) { return false; } } standby(); loraMode(); rxAntEnable(); setFrequency(_frequency); // set LNA boost // todo: implement this //writeRegister(REG_LNA, 0x96); setModulationParams(_sf, _bw, _cr); setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); setTxPower(_txp); // set base addresses uint8_t basebuf[2] = {0}; executeOpcode(OP_BUFFER_BASE_ADDR_8X, basebuf, 2); _radio_online = true; return 1; } void sx128x::end() { // put in sleep mode sleep(); // stop SPI _spiModem.end(); _bitrate = 0; _radio_online = false; _preinit_done = false; } int sx128x::beginPacket(int implicitHeader) { // put in standby mode standby(); if (implicitHeader) { implicitHeaderMode(); } else { explicitHeaderMode(); } _payloadLength = 0; _fifo_tx_addr_ptr = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); return 1; } int sx128x::endPacket() { setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); txAntEnable(); // put in single TX mode uint8_t timeout[3] = {0}; executeOpcode(OP_TX_8X, timeout, 3); uint8_t buf[2]; buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_8X, buf, 2); // wait for TX done while ((buf[1] & IRQ_TX_DONE_MASK_8X) == 0) { buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_8X, buf, 2); yield(); } // clear IRQ's uint8_t mask[2]; mask[0] = 0x00; mask[1] = IRQ_TX_DONE_MASK_8X; executeOpcode(OP_CLEAR_IRQ_STATUS_8X, mask, 2); return 1; } uint8_t sx128x::modemStatus() { // imitate the register status from the sx1276 / 78 uint8_t buf[2] = {0}; executeOpcodeRead(OP_GET_IRQ_STATUS_8X, buf, 2); uint8_t clearbuf[2] = {0}; uint8_t byte = 0x00; if ((buf[0] & IRQ_PREAMBLE_DET_MASK_8X) != 0) { byte = byte | 0x01 | 0x04; // clear register after reading clearbuf[0] = IRQ_PREAMBLE_DET_MASK_8X; } if ((buf[1] & IRQ_HEADER_DET_MASK_8X) != 0) { byte = byte | 0x02 | 0x04; } executeOpcode(OP_CLEAR_IRQ_STATUS_8X, clearbuf, 2); return byte; } uint8_t sx128x::currentRssiRaw() { uint8_t byte = 0; executeOpcodeRead(OP_CURRENT_RSSI_8X, &byte, 1); return byte; } int ISR_VECT sx128x::currentRssi() { uint8_t byte = 0; executeOpcodeRead(OP_CURRENT_RSSI_8X, &byte, 1); int rssi = -byte / 2; return rssi; } uint8_t sx128x::packetRssiRaw() { uint8_t buf[5] = {0}; executeOpcodeRead(OP_PACKET_STATUS_8X, buf, 5); return buf[0]; } int ISR_VECT sx128x::packetRssi() { // may need more calculations here uint8_t buf[5] = {0}; executeOpcodeRead(OP_PACKET_STATUS_8X, buf, 5); int pkt_rssi = -buf[0] / 2; return pkt_rssi; } uint8_t ISR_VECT sx128x::packetSnrRaw() { uint8_t buf[5] = {0}; executeOpcodeRead(OP_PACKET_STATUS_8X, buf, 5); return buf[1]; } float ISR_VECT sx128x::packetSnr() { uint8_t buf[5] = {0}; executeOpcodeRead(OP_PACKET_STATUS_8X, buf, 3); return float(buf[1]) * 0.25; } long sx128x::packetFrequencyError() { int32_t freqError = 0; // todo: implement this, page 120 of sx1280 datasheet const float fError = 0.0; return static_cast(fError); } size_t sx128x::write(uint8_t byte) { return write(&byte, sizeof(byte)); } size_t sx128x::write(const uint8_t *buffer, size_t size) { if ((_payloadLength + size) > MAX_PKT_LENGTH) { size = MAX_PKT_LENGTH - _payloadLength; } // write data writeBuffer(buffer, size); _payloadLength = _payloadLength + size; return size; } int ISR_VECT sx128x::available() { return _rxPacketLength - _packetIndex; } int ISR_VECT sx128x::read() { if (!available()) { return -1; } uint8_t byte = _packet[_packetIndex]; _packetIndex++; return byte; } int sx128x::peek() { if (!available()) { return -1; } uint8_t b = _packet[_packetIndex]; return b; } void sx128x::flush() { } void sx128x::onReceive(void(*callback)(uint8_t, int)) { _onReceive = callback; if (callback) { pinMode(_dio0, INPUT); // set preamble and header detection irqs, plus dio0 mask uint8_t buf[8]; // set irq masks, enable all buf[0] = 0xFF; buf[1] = 0xFF; // set dio0 masks buf[2] = 0x00; buf[3] = IRQ_RX_DONE_MASK_8X; // set dio1 masks buf[4] = 0x00; buf[5] = 0x00; // set dio2 masks buf[6] = 0x00; buf[7] = 0x00; executeOpcode(OP_SET_IRQ_FLAGS_8X, buf, 8); //#ifdef SPI_HAS_NOTUSINGINTERRUPT // _spiModem.usingInterrupt(digitalPinToInterrupt(_dio0)); //#endif // make function available extern void onDio0Rise(); attachInterrupt(digitalPinToInterrupt(_dio0), onDio0Rise, RISING); } else { detachInterrupt(digitalPinToInterrupt(_dio0)); //#ifdef SPI_HAS_NOTUSINGINTERRUPT // _spiModem.notUsingInterrupt(digitalPinToInterrupt(_dio0)); //#endif } } void sx128x::receive(int size) { if (size > 0) { implicitHeaderMode(); // tell radio payload length _rxPacketLength = size; //_payloadLength = size; //setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } else { explicitHeaderMode(); } rxAntEnable(); uint8_t mode[3] = {0xFF, 0xFF, 0xFF}; // continuous mode executeOpcode(OP_RX_8X, mode, 3); } void sx128x::standby() { uint8_t byte; if (_tcxo) { // STDBY_XOSC byte = 0x01; } else { // STDBY_RC byte = 0x00; } executeOpcode(OP_STANDBY_8X, &byte, 1); } void sx128x::sleep() { uint8_t byte = 0x00; executeOpcode(OP_SLEEP_8X, &byte, 1); } void sx128x::enableTCXO() { // todo: need to check how to implement on sx1280 } void sx128x::disableTCXO() { // todo: need to check how to implement on sx1280 } void sx128x::setTxPower(int level, int outputPin) { if (level > 13) { level = 13; } else if (level < -18) { level = -18; } _txp = level; level = level + 18; uint8_t tx_buf[2]; tx_buf[0] = level; tx_buf[1] = 0xE0; // ramping time - 20 microseconds executeOpcode(OP_TX_PARAMS_8X, tx_buf, 2); } uint8_t sx128x::getTxPower() { return _txp; } void sx128x::setFrequency(uint32_t frequency) { _frequency = frequency; uint8_t buf[3]; uint32_t freq = (uint32_t)((double)frequency / (double)FREQ_STEP_8X); buf[0] = ((freq >> 16) & 0xFF); buf[1] = ((freq >> 8) & 0xFF); buf[2] = (freq & 0xFF); executeOpcode(OP_RF_FREQ_8X, buf, 3); } uint32_t sx128x::getFrequency() { // we can't read the frequency on the sx1280 uint32_t frequency = _frequency; return frequency; } void sx128x::setSpreadingFactor(int sf) { if (sf < 5) { sf = 5; } else if (sf > 12) { sf = 12; } _sf = sf; setModulationParams(sf, _bw, _cr); handleLowDataRate(); } uint8_t sx128x::getSpreadingFactor() { return _sf; } uint32_t sx128x::getSignalBandwidth() { int bw = _bw; switch (bw) { case 0x34: return 203.125E3; case 0x26: return 406.25E3; case 0x18: return 812.5E3; case 0x0A: return 1625E3; } return 0; } void sx128x::handleLowDataRate(){ // todo: do i need this?? } void sx128x::optimizeModemSensitivity(){ // todo: check if there's anything the sx1280 can do here } void sx128x::setSignalBandwidth(uint32_t sbw) { if (sbw <= 203.125E3) { _bw = 0x34; } else if (sbw <= 406.25E3) { _bw = 0x26; } else if (sbw <= 812.5E3) { _bw = 0x18; } else { _bw = 0x0A; } setModulationParams(_sf, _bw, _cr); handleLowDataRate(); optimizeModemSensitivity(); } void sx128x::setCodingRate4(int denominator) { if (denominator < 5) { denominator = 5; } else if (denominator > 8) { denominator = 8; } _cr = denominator - 4; // todo: add support for new interleaving scheme, see page 117 of sx1280 // datasheet // update cr values for sx1280's use setModulationParams(_sf, _bw, _cr); } uint8_t sx128x::getCodingRate4() { return _cr + 4; } void sx128x::setPreambleLength(long length) { _preambleLength = length; setPacketParams(length, _implicitHeaderMode, _payloadLength, _crcMode); } void sx128x::setSyncWord(int sw) { // not implemented } void sx128x::enableCrc() { _crcMode = 0x20; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void sx128x::disableCrc() { _crcMode = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } byte sx128x::random() { // todo: implement } void sx128x::setSPIFrequency(uint32_t frequency) { _spiSettings = SPISettings(frequency, MSBFIRST, SPI_MODE0); } void sx128x::dumpRegisters(Stream& out) { for (int i = 0; i < 128; i++) { out.print("0x"); out.print(i, HEX); out.print(": 0x"); out.println(readRegister(i), HEX); } } void sx128x::explicitHeaderMode() { _implicitHeaderMode = 0; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void sx128x::implicitHeaderMode() { _implicitHeaderMode = 0x80; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } void ISR_VECT sx128x::handleDio0Rise() { uint8_t buf[2]; buf[0] = 0x00; buf[1] = 0x00; executeOpcodeRead(OP_GET_IRQ_STATUS_8X, buf, 2); executeOpcode(OP_CLEAR_IRQ_STATUS_8X, buf, 2); if ((buf[1] & IRQ_PAYLOAD_CRC_ERROR_MASK_8X) == 0) { // received a packet _packetIndex = 0; uint8_t rxbuf[2] = {0}; executeOpcodeRead(OP_RX_BUFFER_STATUS_8X, rxbuf, 2); _rxPacketLength = rxbuf[0]; _fifo_rx_addr_ptr = rxbuf[1]; readBuffer(_packet, _rxPacketLength); if (_onReceive) { _onReceive(_index, _rxPacketLength); } } } void sx128x::updateBitrate() { if (_radio_online) { _lora_symbol_rate = (float)getSignalBandwidth()/(float)(pow(2, _sf)); _lora_symbol_time_ms = (1.0/_lora_symbol_rate)*1000.0; _bitrate = (uint32_t)(_sf * ( (4.0/(float)(_cr+4)) / ((float)(pow(2, _sf))/((float)getSignalBandwidth()/1000.0)) ) * 1000.0); _lora_us_per_byte = 1000000.0/((float)_bitrate/8.0); //_csma_slot_ms = _lora_symbol_time_ms*10; float target_preamble_symbols = (LORA_PREAMBLE_TARGET_MS/_lora_symbol_time_ms)-LORA_PREAMBLE_SYMBOLS_HW; if (target_preamble_symbols < LORA_PREAMBLE_SYMBOLS_MIN) { target_preamble_symbols = LORA_PREAMBLE_SYMBOLS_MIN; } else { target_preamble_symbols = ceil(target_preamble_symbols); } _preambleLength = (long)target_preamble_symbols; setPacketParams(_preambleLength, _implicitHeaderMode, _payloadLength, _crcMode); } else { _bitrate = 0; } }