Add alternative SX1276 lora driver (#24373)

2026-07-28 04:15:53 +00:00 · 2026-01-21 13:02:25 +01:00
parent 0c8b065de5
commit d48c7d3464
2 changed files with 141 additions and 0 deletions
@@ -0,0 +1,129 @@
+/*
+  xdrv_73_3_lora_sx127x_v2.ino - LoRa support for Tasmota
+
+  SPDX-FileCopyrightText: 2024 Theo Arends
+
+  SPDX-License-Identifier: GPL-3.0-only                                                                                 
+*/
+
+#ifdef USE_SPI
+#ifdef USE_SPI_LORA
+#ifdef USE_LORA_SX127X
+/*********************************************************************************************\
+ * Legacy Semtech SX1276/77/78/79 Long Range (LoRa)
+ * - HopeRF RFM95W, RFM96W and RFM98W
+ * - LilyGo TTGO T3 LoRa32 868MHz ESP32 (uses SX1276)
+ * - LilyGo TTGO T-Higrow 868MHz (uses SX1276)
+ * - DFRobot FireBeetle Covers LoRa Radio 868MHz (uses SX1278)
+ * - M5Stack LoRa868 (uses AI-01 which uses SX1276)
+ * - Modtronix
+ * 
+ * Used GPIO's:
+ * - SPI_CLK
+ * - SPI_MISO 
+ * - SPI_MOSI
+ * - LoRa_CS
+ * - LoRa_Rst
+ * - Lora_DIO0
+ * - Lora_DIO1 (busy)
+\*********************************************************************************************/
+
+#include <RadioLib.h>
+SX1276 LoRaRadio7x = nullptr;              // Select LoRa support
+
+void IRAM_ATTR LoraSx127xV2OnReceive(void);
+void LoraSx127xV2OnReceive(void) {
+  if (!Lora->send_flag && !Lora->received_flag) {
+    Lora->receive_time = millis();
+  }
+  Lora->received_flag = true;              // we got a packet, set the flag
+}
+
+bool LoraSx127xV2Available(void) {
+  if (Lora->send_flag) {
+    Lora->received_flag = false;           // Reset receive flag as it was caused by send interrupt
+
+    uint32_t time = millis();
+    int state = LoRaRadio.startReceive();  // Put module back to listen mode
+    Lora->send_flag = false;
+    if (state != RADIOLIB_ERR_NONE) {
+      AddLog(LOG_LEVEL_DEBUG_MORE, PSTR("S6X: Rcvd (%d) restarted (%d)"), time, state);
+    }
+  }
+  return Lora->received_flag;              // Check if the receive flag is set
+}
+
+int LoraSx127xV2Receive(char* data) {
+  Lora->received_flag = false;             // Reset flag
+  int packet_size = LoRaRadio7x.getPacketLength();
+  int state = LoRaRadio7x.readData((uint8_t*)data, TAS_LORA_MAX_PACKET_LENGTH -1);
+  // LoRaWan downlink frames are sent without CRC, which will raise error on SX127x. We can ignore that error
+  if (RADIOLIB_ERR_CRC_MISMATCH == state) {
+    state = RADIOLIB_ERR_NONE;
+    AddLog(LOG_LEVEL_DEBUG, PSTR("S7X: Ignoring CRC error"));
+  }
+  if (RADIOLIB_ERR_NONE == state) { 
+    Lora->rssi = LoRaRadio7x.getRSSI();
+    Lora->snr = LoRaRadio7x.getSNR();
+  } else {
+    packet_size = 0;                       // Some other error occurred
+    AddLog(LOG_LEVEL_DEBUG, PSTR("S7X: Receive error %d"), state);
+  }
+  return packet_size;
+}
+
+bool LoraSx127xV2Send(uint8_t* data, uint32_t len, bool invert) {
+  int state1 = RADIOLIB_ERR_NONE;
+  int state2 = RADIOLIB_ERR_NONE;
+  if (invert) {
+    LoRaRadio7x.standby();
+    state1 = LoRaRadio7x.invertIQ(true);
+  }
+  int state = LoRaRadio7x.transmit(data, len);
+  Lora->send_flag = true;                  // Use this flag as LoRaRadio.transmit enable send interrupt
+  if (invert) {
+    state2 = LoRaRadio7x.invertIQ(false);
+    LoRaRadio7x.standby();
+  }
+  if (state != RADIOLIB_ERR_NONE || state1 != RADIOLIB_ERR_NONE || state2 != RADIOLIB_ERR_NONE) {
+    AddLog(LOG_LEVEL_DEBUG, PSTR("S7X: Send error %d %d %d"), state1, state, state2);
+  }
+  return (RADIOLIB_ERR_NONE == state);
+}
+
+bool LoraSx127xV2Config(bool full) {
+  LoRaRadio7x.setSpreadingFactor(Lora->settings.spreading_factor);
+  LoRaRadio7x.setBandwidth(Lora->settings.bandwidth);
+  LoRaRadio7x.setFrequency(Lora->settings.frequency);
+  if (full) {
+    LoRaRadio7x.setCodingRate(Lora->settings.coding_rate);
+    LoRaRadio7x.setSyncWord(Lora->settings.sync_word);
+    LoRaRadio7x.setPreambleLength(Lora->settings.preamble_length);
+    LoRaRadio7x.setCurrentLimit(Lora->settings.current_limit);
+    LoRaRadio7x.setCRC(Lora->settings.crc_bytes);
+    LoRaRadio7x.setOutputPower(Lora->settings.output_power);
+    if (Lora->settings.implicit_header) { 
+      LoRaRadio7x.implicitHeader(Lora->settings.implicit_header);
+    } else { 
+      LoRaRadio7x.explicitHeader();
+    }
+    LoRaRadio7x.invertIQ(false);
+  }
+  return true;
+}
+
+bool LoraSx127xV2Init(void) {
+  LoRaRadio7x = new Module(Pin(GPIO_LORA_CS), Pin(GPIO_LORA_DI0), Pin(GPIO_LORA_RST), Pin(GPIO_LORA_DI1));
+  if (RADIOLIB_ERR_NONE == LoRaRadio7x.begin(Lora->settings.frequency)) {
+    LoraSx127xV2Config(true);
+    LoRaRadio7x.setPacketReceivedAction(LoraSx127xV2OnReceive);
+    if (RADIOLIB_ERR_NONE == LoRaRadio7x.startReceive()) {
+      return true;
+    }
+  }
+  return false;
+}
+
+#endif  // USE_LORA_SX127X
+#endif  // USE_SPI_LORA
+#endif  // USE_SPI
@@ -291,6 +291,18 @@ void LoraInit(void) {
      // Need this as following `else if`s may not be present
    }
 #ifdef USE_LORA_SX127X
+    else if (PinUsed(GPIO_LORA_DI0) && PinUsed(GPIO_LORA_DI1)) {
+      // SX1276, RFM95W
+      if (LoraSx127xV2Init()) {
+        Lora->Config    = &LoraSx127xV2Config;
+        Lora->Available = &LoraSx127xV2Available;
+        Lora->Receive   = &LoraSx127xV2Receive;
+        Lora->Send      = &LoraSx127xV2Send;
+        Lora->Init      = &LoraSx127xV2Init;
+        strcpy_P(hardware, PSTR("SX127x"));
+        present = true;
+      }
+    }
    else if (PinUsed(GPIO_LORA_DI0)) {
      // SX1276, RFM95W
      if (LoraSx127xInit()) {