ESP-NTP-MQTT

This project uses an ESP8266 to connect to our local NTP server to display the time on a MAX7219 8x8x4 LED Matrix.

It is possible to also a public NTP pool/server following an overhaul of the code!

In addition, the ESP8266 subscribes to an MQTT topic and scrolls messages. I schedule messages from Home Assistant - they run on pre-defined times and give info like weather & 3D printer status. Demo gif is below.

You will need to insert an NTP server, SSID/Password, MQTT Server, User & Password, plus check the number of MAX7219 displays is correct.

A note on NTP:

NTP servers are located all over the world, so it's best to use an NTP server that is physically close to you for best performance.

NTP pools are are clusters of public time servers and are grouped into localities.

If you can spare the resources and would like another project, try setting up a Chrony server (can run in a Docker container!). You can then serve multiple clocks and your whole network from a local server, reducing the load on the NTP pool.

Libraries:

A number of other libraries are required. These are below!

1. ESP8266 libs: https://github.com/esp8266/Arduino
2. PubSubClient: https://github.com/knolleary/pubsubclient
3. Adafruit-GFX: https://github.com/adafruit/Adafruit-GFX-Library
4. Max72xxPanel: https://github.com/markruys/arduino-Max72xxPanel

Demo:

Display rotation:

If your displays are upside down, see issue (#1).

This code may help you:

matrix.setPosition(0, 3, 0); // (Display-Nr ab Einspeisung, X, Y)
matrix.setPosition(1, 2, 0);
matrix.setPosition(2, 1, 0);
matrix.setPosition(3, 0, 0);

matrix.fillScreen(0);

matrix.setIntensity(0); // Use a value between 0 and 15 for brightness
matrix.setRotation(0, 3); // The first display is position upside down
matrix.setRotation(1, 3); // The first display is position upside down
matrix.setRotation(2, 3); // The first display is position upside down
matrix.setRotation(3, 3); // The first display is position upside down
display_message("Ready");