ESP8266 Clock

main.cpp

#include <Arduino.h>
#include <SPI.h>
#include <ESP8266WiFi.h>
#include <MD_Parola.h>
#include <MD_ParolaExt.h>
#include <MD_MAX72xx.h>
#include <ESP8266TimerInterrupt.h>
#include <WiFiUdp.h>
#include <NTPClient.h>
#include <time.h>

#define HARDWARE_TYPE MD_MAX72XX::FC16_HW
#define MAX_DEVICES 8
#define CS0 SS
#define CS1 16

ESP8266TimerInterrupt timer;
MD_ParolaExt* line1;
MD_ParolaExt* line2;
WiFiUDP ntpUdp;
NTPClient* timeClient;

const char* wifiSsid = "Tuldok-House";
const char* wifiPass = "HelloWorld1234";
const char* timezone = "PST-8";

void timerTick();
void connectWiFi();
void initTime();
void initHwSpi();
void displayInit();

void setup()
{
  Serial.begin(2000000, SERIAL_8N1);
  connectWiFi();
  initTime();
  initHwSpi();
  displayInit();

  timer.attachInterruptInterval(1000, &timerTick);
}

void loop() {
  timeClient->update();
  struct timeval tvx;
  tvx.tv_sec = timeClient->getEpochTime();
  tvx.tv_usec = 0;
  settimeofday(&tvx, NULL);
  delay(500);
}

void connectWiFi()
{
  WiFi.begin(wifiSsid, wifiPass);

  while(WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(500);
  }

  Serial.println("WiFi connected.");
}

void IRAM_ATTR timerTick()
{
  struct tm timeinfo;
  getLocalTime(&timeinfo);
  line1->setTextAlignment(PA_CENTER);
  line1->printExt(&timeinfo, "%m/%d/%Y");
  line2->setTextAlignment(PA_CENTER);
  line2->printExt(&timeinfo, "%I:%M:%S %P");
}

void initTime()
{
  timeClient = new NTPClient(ntpUdp, "pool.ntp.org", 0, 60000);
  setenv("TZ", timezone, 1);
  tzset();
}

void displayInit()
{
  line1 = new MD_ParolaExt(HARDWARE_TYPE, SPI, CS0, MAX_DEVICES);
  line2 = new MD_ParolaExt(HARDWARE_TYPE, SPI, CS1, MAX_DEVICES);

  line1->begin();
  line2->begin();
  line1->setIntensity(15);
  line2->setIntensity(15);
  line1->displayClear();
  line2->displayClear();
}

void initHwSpi()
{
  SPI.setFrequency(10000000);
  SPI.begin();
  pinMode(CS0, OUTPUT);
  pinMode(CS1, OUTPUT);
}

MD_Parola.h

#pragma once

#include <MD_Parola.h>

class MD_ParolaExt : public MD_Parola
{
    public:
    MD_ParolaExt(MD_MAX72XX::moduleType_t mod, SPIClass &spi, uint8_t csPin, uint8_t numDevices = 1);
    size_t printExt(struct tm* timeinfo, const char* format = NULL);
    virtual ~MD_ParolaExt() = default;
};

MD_ParolaExt.cpp

#include <MD_Parola.h>
#include "MD_ParolaExt.h"

size_t MD_ParolaExt::printExt(tm *timeinfo, const char *format)
{
    const char* f = format;
    if (!f)
    {
        f = "%c";
    }

    char buf[64];
    size_t written = strftime(buf, 64, f, timeinfo);

    if (written == 0) {
        return written;
    }

    return MD_Parola::print(buf);
}

MD_ParolaExt::MD_ParolaExt(MD_MAX72XX::moduleType_t mod, SPIClass &spi, uint8_t csPin, uint8_t numDevices) : MD_Parola(mod, spi, csPin, numDevices)
{
}