add Gateway_sleepMCU example

Examples/Gateway_sleepMCU/Gateway_sleepMCU.ino

@@ -0,0 +1,81 @@
+// Sample RFM69 receiver/gateway sketch, with ACK and optional encryption
+// MCU in SLEEP_FOREVER, radio in active RX mode
+// Passes through any wireless received messages to the serial port & responds to ACKs
+// Library and code by Felix Rusu - felix@lowpowerlab.com
+//****************************************************************************************************************
+#include <RFM69.h>    //get it here: https://www.github.com/lowpowerlab/rfm69
+#include <RFM69_ATC.h>
+#include <LowPower.h> //get it here: https://www.github.com/lowpowerlab/lowpower
+//****************************************************************************************************************
+#define NODEID        1    //keep Gateways at ID=1
+#define NETWORKID     100  //the same on all nodes that talk to each other
+//Match frequency to the hardware version of the radio on your Moteino (uncomment one):
+//#define FREQUENCY     RF69_433MHZ
+//#define FREQUENCY     RF69_868MHZ
+#define FREQUENCY     RF69_915MHZ
+//#define FREQUENCY_EXACT 917000000 //uncomment to set to a specific frequency
+#define IS_RFM69HW_HCW    //uncomment only for RFM69HW! Leave out if you have RFM69W!
+#define ENABLE_ATC    //AUTO TRANSMISSION CONTROL - comment out to disable it
+#define ENCRYPTKEY    "sampleEncryptKey" //exactly the same 16 characters/bytes on all nodes!
+#define SERIAL_BAUD   115200
+//****************************************************************************************************************
+#ifdef ENABLE_ATC
+  RFM69_ATC radio;
+#else
+  RFM69 radio;
+#endif
+
+char buff[61];
+void setup() {
+  Serial.begin(SERIAL_BAUD);
+  radio.initialize(FREQUENCY,NODEID,NETWORKID);
+#ifdef IS_RFM69HW
+  radio.setHighPower(); //only for RFM69HW!
+#endif
+#ifdef ENCRYPTKEY
+  radio.encrypt(ENCRYPTKEY);
+#endif
+
+#ifdef FREQUENCY_EXACT
+  radio.setFrequency(FREQUENCY_EXACT); //set frequency to some custom frequency
+#endif
+
+  sprintf(buff, "\nListening at %lu Mhz...", radio.getFrequency()/1000000L);
+
+#ifdef ENABLE_ATC
+  Serial.println("RFM69_ATC Enabled (Auto Transmission Control)");
+#endif
+
+  pinMode(LED_BUILTIN, OUTPUT);
+}
+
+uint32_t packetCount = 0;
+
+void loop() {
+  //ensure radio in RX mode before sleeping
+  radio.receiveDone(); //this checks if a packet is ready and processes it (saves it in lib buffer), or else puts radio in RX mode
+
+  Serial.println("FOREVER SLEEP...");
+  Serial.flush();
+
+  LowPower.powerDown(SLEEP_FOREVER, ADC_OFF, BOD_OFF); //sleep the MCU
+
+  if (radio.receiveDone()) //WAKEUP by radio interrupt!
+  {
+    digitalWrite(LED_BUILTIN, HIGH);
+    Serial.print("#[");
+    Serial.print(++packetCount);
+    Serial.print(']');
+    Serial.print('[');Serial.print(radio.SENDERID, DEC);Serial.print("] ");
+
+    for (byte i = 0; i < radio.DATALEN; i++)
+      Serial.print((char)radio.DATA[i]);
+
+    Serial.print("  [RSSI:");Serial.print(radio.RSSI);Serial.print("]");
+
+    if (radio.ACKRequested()) radio.sendACK();
+
+    Serial.println();
+    digitalWrite(LED_BUILTIN, LOW);
+  }
+}