add gateway voltage sending example

examples/Gateway_Examples/Repeater_Voltage/Repeater_Voltage.ino

@@ -0,0 +1,31 @@
+#define GTWY_READING_ID 42
+#define INTERVAL_SECONDS 60
+#define ADC_PIN 34
+
+#include "fdrs_gateway_config.h"
+#include <fdrs_gateway.h>
+int vref = 1100;
+
+float getVoltage() {
+  uint16_t v = analogRead(ADC_PIN);
+  float battery_voltage = ((float)v / 4095.0) * 2.0 * 3.3 * (vref / 1000.0);
+  String voltage = "Voltage :" + String(battery_voltage) + "V";
+  DBG(voltage);
+  return battery_voltage;
+}
+void sendReading() {
+  float v = getVoltage();
+  loadFDRS(v, VOLTAGE_T, GTWY_READING_ID);
+  sendFDRS();
+}
+
+void setup() {
+  beginFDRS();
+  sendReading();
+  scheduleFDRS(sendReading, INTERVAL_SECONDS * 1000);
+  sendReading();
+}
+
+void loop() {
+  loopFDRS();
+}

examples/Gateway_Examples/Repeater_Voltage/fdrs_gateway_config.h

@@ -0,0 +1,80 @@
+//  FARM DATA RELAY SYSTEM
+//
+//  GATEWAY CONFIGURATION
+
+//Addresses
+#define UNIT_MAC           0x02  // The address of this gateway
+
+#define ESPNOW_NEIGHBOR_1  0x01  // Address of ESP-NOW neighbor #1
+#define ESPNOW_NEIGHBOR_2  0x04  // Address of ESP-NOW neighbor #2
+#define LORA_NEIGHBOR_1    0x00  // Address of LoRa neighbor #1
+#define LORA_NEIGHBOR_2    0x00  // Address of LoRa neighbor #2
+
+// Interfaces
+#define USE_ESPNOW  
+//#define USE_LORA
+//#define USE_WIFI  // Will cause errors if used with ESP-NOW. Use a serial link instead!
+//#define USE_ETHERNET
+
+// Routing
+// Options: sendESPNowNbr(1 or 2); sendESPNowPeers(); sendLoRaNbr(1 or 2); broadcastLoRa(); sendSerial(); sendMQTT();
+#define ESPNOWG_ACT    sendESPNowNbr(1);
+#define LORAG_ACT      
+#define SERIAL_ACT     
+#define MQTT_ACT          
+#define INTERNAL_ACT   sendESPNowNbr(1);
+#define ESPNOW1_ACT    sendESPNowNbr(2); sendESPNowPeers();
+#define ESPNOW2_ACT    sendESPNowNbr(1);                
+#define LORA1_ACT      
+#define LORA2_ACT 
+
+// LoRa Configuration
+#define RADIOLIB_MODULE SX1276
+#define LORA_SS    18
+#define LORA_RST   14
+#define LORA_DIO   26
+#define LORA_BUSY  33
+//#define USE_SX126X
+
+#define LORA_TXPWR 17   // LoRa TX power in dBm (: +2dBm - +17dBm (for SX1276-7) +20dBm (for SX1278))
+
+//#define CUSTOM_SPI
+#define LORA_SPI_SCK  5
+#define LORA_SPI_MISO 19
+#define LORA_SPI_MOSI 27
+
+#define FDRS_DEBUG     // Enable USB-Serial debugging
+
+// OLED -- Displays console debugging messages on an SSD1306 I²C OLED
+///#define USE_OLED    
+#define OLED_HEADER "FDRS"
+#define OLED_PAGE_SECS 30
+#define OLED_SDA 4
+#define OLED_SCL 15
+#define OLED_RST 16
+
+// UART data interface pins (if available)
+#define RXD2 14
+#define TXD2 15
+
+//#define USE_LR  // Use ESP-NOW LR mode (ESP32 only)
+
+// WiFi and MQTT Credentials  -- These will override the global settings
+//#define WIFI_SSID   "Your SSID"  
+//#define WIFI_PASS   "Your Password"
+
+//#define MQTT_ADDR   "192.168.0.8"
+//#define MQTT_PORT   1883 // Default MQTT port is 1883
+//#define MQTT_AUTH   //Enable MQTT authentication 
+//#define MQTT_USER   "Your MQTT Username"
+//#define MQTT_PASS   "Your MQTT Password"
+
+// NTP Time settings
+#define USDST
+// #define EUDST
+#define TIME_SERVER           "0.us.pool.ntp.org"     // NTP time server to use. If FQDN at least one DNS server is required to resolve name
+#define STD_OFFSET      (-6)                // Local standard time offset in hours from UTC - if unsure, check https://time.is
+#define DST_OFFSET      (STD_OFFSET + 1)    // Local savings time offset in hours from UTC - if unsure, check https://time.is
+#define TIME_FETCHNTP     15      // Time, in minutes, between fetching time from NTP server
+#define TIME_PRINTTIME    10      // Time, in minutes, between printing local time to debug
+#define TIME_SEND_INTERVAL 15    // Time, in minutes, between sending out time to remote devices, set to 0 to only send when time is received