jacob.eva/opencom_xl_firmware
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
f229b78372
opencom_xl_firmware/sx127x.cpp
Mark Qvist f229b78372 Cleanup
2024-02-12 13:37:10 +01:00

498 lines
15 KiB
C++
Raw Blame History

// Copyright (c) Sandeep Mistry. All rights reserved.
// Licensed under the MIT license.
// Modifications and additions copyright 2023 by Mark Qvist
// Obviously still under the MIT license.
#include "Boards.h"
#if MODEM == SX1276
#include "sx127x.h"
#if MCU_VARIANT == MCU_ESP32
#if MCU_VARIANT == MCU_ESP32 and !defined(CONFIG_IDF_TARGET_ESP32S3)
#include "soc/rtc_wdt.h"
#endif
#define ISR_VECT IRAM_ATTR
#else
#define ISR_VECT
#endif
// 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 MAX_PKT_LENGTH 255
#define SYNC_WORD_7X 0x12
extern SPIClass SPI;
sx127x::sx127x() :
_spiSettings(8E6, MSBFIRST, SPI_MODE0),
_ss(LORA_DEFAULT_SS_PIN), _reset(LORA_DEFAULT_RESET_PIN), _dio0(LORA_DEFAULT_DIO0_PIN),
_frequency(0),
_packetIndex(0),
_preinit_done(false),
_onReceive(NULL) { setTimeout(0); }
void sx127x::setSPIFrequency(uint32_t frequency) { _spiSettings = SPISettings(frequency, MSBFIRST, SPI_MODE0); }
void sx127x::setPins(int ss, int reset, int dio0, int busy) { _ss = ss; _reset = reset; _dio0 = dio0; _busy = busy; }
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::idle() { 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);
SPI.begin();
// 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);
SPI.beginTransaction(_spiSettings);
SPI.transfer(address);
response = SPI.transfer(value);
SPI.endTransaction();
digitalWrite(_ss, HIGH);
return response;
}
int sx127x::begin(long frequency) {
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);
idle();
return 1;
}
void sx127x::end() {
sleep();
SPI.end();
_preinit_done = false;
}
int sx127x::beginPacket(int implicitHeader) {
idle();
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<int32_t>(readRegister(REG_FREQ_ERROR_MSB_7X) & B111);
freqError <<= 8L;
freqError += static_cast<int32_t>(readRegister(REG_FREQ_ERROR_MID_7X));
freqError <<= 8L;
freqError += static_cast<int32_t>(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<float>(freqError) * (1L << 24)) / fXtal) * (getSignalBandwidth() / 500000.0f);
return static_cast<long>(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)(int)) {
_onReceive = callback;
if (callback) {
pinMode(_dio0, INPUT);
writeRegister(REG_DIO_MAPPING_1_7X, 0x00);
#ifdef SPI_HAS_NOTUSINGINTERRUPT
SPI.usingInterrupt(digitalPinToInterrupt(_dio0));
#endif
attachInterrupt(digitalPinToInterrupt(_dio0), sx127x::onDio0Rise, RISING);
} else {
detachInterrupt(digitalPinToInterrupt(_dio0));
#ifdef SPI_HAS_NOTUSINGINTERRUPT
SPI.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(unsigned long 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);
}
writeRegister(REG_MODEM_CONFIG_2_7X, (readRegister(REG_MODEM_CONFIG_2_7X) & 0x0f) | ((sf << 4) & 0xf0));
handleLowDataRate();
}
long 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(long 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;
writeRegister(REG_MODEM_CONFIG_1_7X, (readRegister(REG_MODEM_CONFIG_1_7X) & 0xf1) | (cr << 1));
}
void sx127x::setPreambleLength(long 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<<sf) / (getSignalBandwidth()/1000)) > 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(packetLength); }
writeRegister(REG_FIFO_ADDR_PTR_7X, 0);
}
}
void ISR_VECT sx127x::onDio0Rise() { sx127x_modem.handleDio0Rise(); }
sx127x sx127x_modem;
#endif
Reference in New Issue View Git Blame Copy Permalink