Simple LoRaNicator test sketch for LCD and radio rx

SimpleRX.ino

// LoRaNicator simple LCD and radio RX test

#include <SPI.h>
#include <RH_RF95.h>
#include <U8g2lib.h>

#define RFM95_CS 14
#define RFM95_RST 13
#define RFM95_INT 6
#define RF95_FREQ 868.0

const int hold = A2;

RH_RF95 rf95(RFM95_CS, RFM95_INT);

U8G2_ST7565_NHD_C12864_F_4W_HW_SPI u8g2(U8G2_R2, /* cs=*/ A4, /* dc=*/ A6, /* reset=*/ A5);


void setup() 
{
  pinMode(LED_BUILTIN, OUTPUT); 
  digitalWrite(LED_BUILTIN, HIGH);
  pinMode(hold, OUTPUT);
  digitalWrite(hold, HIGH);
  
  pinMode(RFM95_RST, OUTPUT);
  digitalWrite(RFM95_RST, HIGH);


  Serial.begin(9600);
  delay(100);

  Serial.println("Arduino LoRa RX Test!");
  
  // reset RFM95
  digitalWrite(RFM95_RST, LOW);
  delay(10);
  digitalWrite(RFM95_RST, HIGH);
  delay(10);

  while (!rf95.init()) {
    Serial.println("LoRa radio init failed");
    while (1);
  }
  Serial.println("LoRa radio init OK!");

  // Defaults after init are 868.0MHz, modulation GFSK_Rb250Fd250, +13dbM
  if (!rf95.setFrequency(RF95_FREQ)) {
    Serial.println("setFrequency failed");
    while (1);
  }
  Serial.print("Set Freq to: "); Serial.println(RF95_FREQ);


  rf95.setTxPower(23, false);

  u8g2.begin();
  u8g2.setContrast(150);
  delay(1000);

  u8g2.clearBuffer();
  u8g2.drawRFrame(0,   0, 128,  10, 3);
  u8g2.drawRFrame(0,  11, 128,  53, 3);
  u8g2.setFont(u8g2_font_5x7_tr);
  u8g2.drawStr(2,8, "LoRaNicator");
  u8g2.sendBuffer();

}




void loop()
{

    if (rf95.available())
  { 
      uint8_t buf[RH_RF95_MAX_MESSAGE_LEN];
      uint8_t len = sizeof(buf);
    
    if (rf95.recv(buf, &len))
    {
      digitalWrite(LED_BUILTIN, LOW);
      RH_RF95::printBuffer("Received: ", buf, len);
      Serial.print("Got: ");
      Serial.println((char*)buf);
      u8g2.clearBuffer();
      u8g2.drawStr(2,22,((char*)buf));
      u8g2.drawRFrame(0,   0, 128,  10, 3);
      u8g2.drawRFrame(0,  11, 128,  53, 3);
      u8g2.drawStr(2,8, "LoRaNicator");
      u8g2.sendBuffer();
      Serial.print("RSSI: ");
      Serial.println(rf95.lastRssi(), DEC);
      
    }
    else
    {
      Serial.println("Receive failed");
    }
  
  }
      digitalWrite(LED_BUILTIN, HIGH);
}