Clocks with no Knobs

This digital clock has no setting or control knobs because the date and time are automatically set using the accurate internet time. Email parts@robotsforfun.com to get the parts for this project.

Before you attempt to do this, you need to first know how to work with the ESP8266 WiFi module.

	Parts needed: ESP8266-12 Jumbo 7-segment common cathode LED displays 5x MAX7219 controller data sheet UDN2981A data sheet 150 ohm resistors 8x 330 ohm resistor (optional for the decimal point) 9V to 3.3V converter 9V power supply Wires Soldering iron

1	Connect the MAX7219 to the 7-segment common cathode LED displays as follows: DIG0 to DIG4 from the MAX7219 to each of the display's common cathode SEGA to SEGG and SEGDP from the MAX7219 to the eight inputs of the UDN2981A The seven corresponding segment outputs of the UDN2981A to the display's segments via a 150 ohm resistor Use the 330 ohm resistor for the decimal point (optional)

MAX7219	UDN2981A	LED digit	Power	Description
2		Common cathode		Digit 0 (leftmost digit)
11		Common cathode		Digit 1
6		Common cathode		Digit 2
7		Common cathode		Digit 3
3		Common cathode		Digit 4
14	11	11	Segment A
15	10	10	Segment F
16	7	7	Segment B
17	5	5	Segment G
20	4	4	Segment C
21	1	1	Segment E
22	3	3	Segment DP
23	2	2	Segment D

2 Here's the code. It's real long!

/*
 * 5 digit x 7 segment LED with NO colon display clock using the MAX7129
 * Digits: Common cathode
 * D0 is the leftmost digit
 * 
 * Connections:
 * MAX7219       ESP8266
 * DIN pin 1  to pin D14
 * CLK pin 12 to pin D12
 * CS  pin 13 to pin D13
 * 
 * After uploading this program to the ESP8266-12 module,
 * open the serial monitor and restart the ESP8266 module to 
 * see what IP address is assigned to this webserver,
 * then browse to this IP address.
 * 
 * or
 * 
 * Connect your WiFi to the default ssid 
 *     "WiFi setup ESP8266-xxxx"
 * or to the one you provided, then browse to the IP address
 *     1.2.3.4 
 * for the main page or
 *     1.2.3.4/setup
 * for the WiFi setup page
 * 
 * If the WiFi is not connected then you will have to go to
 * 1.2.3.4/setup to setup the ssid and password
 * 
 * Copyright 2020 Enoch Hwang
 */

 
//////////////////////////////////////////////////////////////
//// VCC voltage stuff
  ADC_MODE(ADC_VCC);


//////////////////////////////////////////////////////////////
//// status LED stuff
#define statusLed 2     // for ESP8266-12


//////////////////////////////////////////////////////////////
//// NTP clock stuff
#include "DateTime_RobotsForFun.h"


//////////////////////////////////////////////////////////////
//// WiFi stuff
#include "WiFi_RobotsForFun.h"

// Do delay without using the delay() function
void nonblockingDelay(int wait) {
  unsigned long timesUp;
  timesUp = millis() + wait;
  while (millis() < timesUp) {
//    flashActivityLed();
    server.handleClient();
    yield();  // must have this to give time to handle wifi background stuff
  }
}


//////////////////////////////////////////////////////////////
//// HTML webpage 
void indexHTML() {
  String msg = "";
  msg += "";
  msg += "";
  msg += ""; // keep fonts consistent between devices
  msg += ""; // auto refresh page every 1 second
  
  msg += "LED Clock";
  msg += "  ";
  msg += "";
  
  msg += "";
  msg += "Jumbo LED Network Clock
";
  msg += "Real time clock for the
5x7 segment LED display
using the MAX7219 controller";
  msg += "
" + formattedTime() + "";
  msg += "";
  msg += "";

  if (!isTimeValid()) {
    msg += "";
    msg += " Year: ";
    msg += " Month: ";
    msg += "       Day: ";
    msg += "
Hour: ";
    msg += "     Minute: ";
    msg += " Second: ";
    msg += "
";
    msg += "";
    msg += "";
  }
  
  // wifi setup and info links
  msg += "IP address: ";
  if (wifiIsConnected) {
    msg += "" + WiFi.localIP().toString() + "";
    msg += "
Wifi setup and info: ";
    msg += "" + WiFi.localIP().toString() + "/setup";
  } else {
    msg += "1.2.3.4";
    msg += "
Wifi setup and info: ";
    msg += "1.2.3.4/setup";
  }

  msg += "";
  msg += "";

  // send webpage to browser
  server.send(200, "text/html", msg);

  // get url arguments and process the command that DO have time delays
  if (server.hasArg("YR")) {
    // set the clock
    int yr, mo, da, hr, mi, se;
    yr = server.arg("YR").toInt();
    mo = server.arg("MO").toInt();
    da = server.arg("DA").toInt();
    hr = server.arg("HR").toInt();
    mi = server.arg("MI").toInt();
    se = server.arg("SE").toInt();
    if (yr == 0) yr = year();
    if (mo == 0) mo = month();
    if (da == 0) da = day();
    if (hr == 0) hr = hour();
    if (mi == 0) mi = minute();
    setClock(yr, mo, da, hr, mi, se);
  }
}


//////////////////////////////////////////////////////////////
//// MAX7219 7x5 LED display stuff
#include "LedControl.h"
#define DIN 14
#define CS  12
#define CLK 13
#define NO 1  // number of MAX72XX devices connected
LedControl led = LedControl(DIN, CLK, CS, NO);
int brightness = 15; // 15=max bright
bool hr12 = true;

void displayClock() {
  const static char w10[7] = {'S','M','T','W','T','F','S'};  // The "T" is changed in the LedControl.h definition
  const static char w1[7]  = {'u','o','u','d','h','r','A'};

  time_t t = time(nullptr);   // get current date/time
  struct tm st = *gmtime(&t); // convert to time structure
  int h = hour12(st);         // extract the parts
  int h24 = hour(st);
  int m = minute(st);
  int s = second(st);
  int w = weekday(st);        // 0=Sunday
  int mo = month(st);
  int d = day(st);
  
  int h10 = h/10;             // separate the 10th and unit digits
  int h1 = h - h10*10;
  int m10 = m/10;
  int m1 = m - m10*10;
  int s10 = s/10;
  int s1 = s - s10*10;
  int mo10 = mo/10;
  int mo1 = mo - mo10*10;
  int d10 = d/10;
  int d1 = d - d10*10;

  // set brightness depending on time of day
  if (h24 < 5) led.setIntensity(0, 2);  // set the brightness
  else if (h24 >= 5 && h24 <= 22) led.setIntensity(0, 15);
  else led.setIntensity(0, 7);

  if (s1 < 7) { // display hour, minute
    led.setDigit(0, 0, h10, false);
    led.setDigit(0, 1, h1, false);
    led.setDigit(0, 3, m10, false);
    led.setDigit(0, 4, m1, false);
//    led.setLed(0, 2, 7, false);     // turn digit 2, segment 7 off
//    led.setLed(0, 2, 3, false);
//    led.setLed(0, 2, 5, true);      // turn digit 2, segment 5 on
    led.setChar(0, 2, ' ', true);     // turn on digit 2 decimal point
    nonblockingDelay(500); // flash the dot
//    led.setLed(0, 2, 7, false);
//    led.setLed(0, 2, 3, true);
//    led.setLed(0, 2, 5, false);
    led.setChar(0, 2, ' ', false);     // turn off digit 2 decimal point
  } else { // display weekday, day
    led.setChar(0, 0, w10[w], false);
    led.setChar(0, 1, w1[w], false);
    led.setChar(0, 2, '-', false);
    led.setDigit(0, 3, d10, false);
    led.setDigit(0, 4, d1, false);    
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(statusLed, OUTPUT);

  //// MAX7219 LED display stuff
  led.shutdown(0, false);  // The MAX72XX is in power-saving mode on startup
  led.setIntensity(0, 15);  // set the brightness 15=max
  led.clearDisplay(0);
  led.setChar(0, 0, 'C', false);
  led.setChar(0, 1, 'o', false);
  led.setChar(0, 2, 'n', false);
  led.setChar(0, 3, 'n', false);
  led.setChar(0, 4, '-', false);

  //// WiFi stuff
  char devicename[] = "Jumbo LED clock";   // optional. change to whatever you want. Use "ping ESP8266" to test
  setupAP(devicename);  // setup access point using default ssid "WiFi setup ESP8266-xxxx" and no password
  IPAddress staticIP(192, 168, 1, 54);     // for the Jumbo LED Network clock
  bool blocking = false;
  if (!setupWiFi(devicename, staticIP, blocking)) {
  // if (!setupWiFi(devicename, blocking)) {   // use DHCP
    led.setChar(0, 0, 'F', false);
    led.setChar(0, 1, 'A', false);
    led.setChar(0, 2, 'I', false);
    led.setChar(0, 3, 'L', false);
    // block for 3 minutes
    unsigned long timeout = millis() + 180000; // 3 minutes
    while(millis() < timeout) {
      flashActivityLed(3000,150,1);
      server.handleClient();
      yield();  // must have this to give time to handle wifi background stuff
    }
    ESP.restart();  // have not connected to the internet in 3 minutes so just reboot
  }
  // connected to wifi

  // set the clock
  while (!setClock(PST)) {
    delay(1000);
  }

  // update systemStartTime and systemStartCount
  systemStartTime = now();
  EEPROM.get(EEPROM_ADDRESS_systemStartCount, systemStartCount);  // get systemStartCount from EEPROM
  systemStartCount++;
  EEPROM.put(EEPROM_ADDRESS_systemStartCount, systemStartCount);
  EEPROM.commit();

}

void loop() {
  static time_t prevDisplay;
  if (now() != prevDisplay) { //update the display only if time has changed
    prevDisplay = now();
//    Serial.println(formattedTime());
    displayClock();
  }
  
  if (APisOn && (millis() > 600000)) turnOffAP(); // turn off AP after 10 minutes
  flashActivityLed();
//  checkWifiConnection();  // reboot if wifi is disconnected
  syncClock(); // need to call this frequently to sync the clock
  server.handleClient();
}

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Clocks with no Knobs