Initial commit: Simple Sensor firmware for Heltec T114 with BME280

- MeshCore-based Simple Sensor firmware
- Heltec T114 without display
- BME280 sensor support (temp/humidity/pressure)
- Radio: 868.856018 MHz, SF7, BW62.5 kHz, CR4/7
- 2-byte path hash
- PlatformIO project

examples/kiss_modem/main.cpp

@@ -0,0 +1,146 @@
+#include <Arduino.h>
+#include <target.h>
+#include <helpers/ArduinoHelpers.h>
+#include <helpers/IdentityStore.h>
+#include "KissModem.h"
+
+#if defined(NRF52_PLATFORM)
+  #include <InternalFileSystem.h>
+#elif defined(RP2040_PLATFORM)
+  #include <LittleFS.h>
+#elif defined(ESP32)
+  #include <SPIFFS.h>
+#endif
+#if defined(KISS_UART_RX) && defined(KISS_UART_TX)
+  #include <HardwareSerial.h>
+#endif
+
+#define NOISE_FLOOR_CALIB_INTERVAL_MS 2000
+#define AGC_RESET_INTERVAL_MS 30000
+
+StdRNG rng;
+mesh::LocalIdentity identity;
+KissModem* modem;
+static uint32_t next_noise_floor_calib_ms = 0;
+static uint32_t next_agc_reset_ms = 0;
+
+void halt() {
+  while (1) ;
+}
+
+void loadOrCreateIdentity() {
+#if defined(NRF52_PLATFORM)
+  InternalFS.begin();
+  IdentityStore store(InternalFS, "");
+#elif defined(ESP32)
+  SPIFFS.begin(true);
+  IdentityStore store(SPIFFS, "/identity");
+#elif defined(RP2040_PLATFORM)
+  LittleFS.begin();
+  IdentityStore store(LittleFS, "/identity");
+  store.begin();
+#else
+  #error "Filesystem not defined"
+#endif
+
+  if (!store.load("_main", identity)) {
+    identity = radio_new_identity();
+    while (identity.pub_key[0] == 0x00 || identity.pub_key[0] == 0xFF) {
+      identity = radio_new_identity();
+    }
+    store.save("_main", identity);
+  }
+}
+
+void onSetRadio(float freq, float bw, uint8_t sf, uint8_t cr) {
+  radio_set_params(freq, bw, sf, cr);
+}
+
+void onSetTxPower(uint8_t power) {
+  radio_set_tx_power(power);
+}
+
+float onGetCurrentRssi() {
+  return radio_driver.getCurrentRSSI();
+}
+
+void onGetStats(uint32_t* rx, uint32_t* tx, uint32_t* errors) {
+  *rx = radio_driver.getPacketsRecv();
+  *tx = radio_driver.getPacketsSent();
+  *errors = radio_driver.getPacketsRecvErrors();
+}
+
+void setup() {
+  board.begin();
+
+  if (!radio_init()) {
+    halt();
+  }
+
+  radio_driver.begin();
+
+  rng.begin(radio_get_rng_seed());
+  loadOrCreateIdentity();
+
+  sensors.begin();
+
+#if defined(KISS_UART_RX) && defined(KISS_UART_TX)
+#if defined(ESP32)
+  Serial1.setPins(KISS_UART_RX, KISS_UART_TX);
+  Serial1.begin(115200);
+#elif defined(NRF52_PLATFORM)
+  ((Uart *)&Serial1)->setPins(KISS_UART_RX, KISS_UART_TX);
+  Serial1.begin(115200);
+#elif defined(RP2040_PLATFORM)
+  ((SerialUART *)&Serial1)->setRX(KISS_UART_RX);
+  ((SerialUART *)&Serial1)->setTX(KISS_UART_TX);
+  Serial1.begin(115200);
+#elif defined(STM32_PLATFORM)
+  ((HardwareSerial *)&Serial1)->setRx(KISS_UART_RX);
+  ((HardwareSerial *)&Serial1)->setTx(KISS_UART_TX);
+  Serial1.begin(115200);
+#else
+  #error "KISS UART not supported on this platform"
+#endif
+  modem = new KissModem(Serial1, identity, rng, radio_driver, board, sensors);
+#else
+  Serial.begin(115200);
+  uint32_t start = millis();
+  while (!Serial && millis() - start < 3000) delay(10);
+  delay(100);
+  modem = new KissModem(Serial, identity, rng, radio_driver, board, sensors);
+#endif
+
+  modem->setRadioCallback(onSetRadio);
+  modem->setTxPowerCallback(onSetTxPower);
+  modem->setGetCurrentRssiCallback(onGetCurrentRssi);
+  modem->setGetStatsCallback(onGetStats);
+  modem->begin();
+}
+
+void loop() {
+  modem->loop();
+
+  if (!modem->isActuallyTransmitting()) {
+    if (!modem->isTxBusy()) {
+      if ((uint32_t)(millis() - next_agc_reset_ms) >= AGC_RESET_INTERVAL_MS) {
+        radio_driver.resetAGC();
+        next_agc_reset_ms = millis();
+      }
+    }
+
+    uint8_t rx_buf[256];
+    int rx_len = radio_driver.recvRaw(rx_buf, sizeof(rx_buf));
+    if (rx_len > 0) {
+      int8_t snr = (int8_t)(radio_driver.getLastSNR() * 4);
+      int8_t rssi = (int8_t)radio_driver.getLastRSSI();
+      modem->onPacketReceived(snr, rssi, rx_buf, rx_len);
+    }
+  }
+
+  if ((uint32_t)(millis() - next_noise_floor_calib_ms) >= NOISE_FLOOR_CALIB_INTERVAL_MS) {
+    radio_driver.triggerNoiseFloorCalibrate(0);
+    next_noise_floor_calib_ms = millis();
+  }
+  radio_driver.loop();
+}