RuudMAX7219 4x Dot matrix moduleOne module was better put together than the other. (soldering on the PCB in a crooked manner) I thought that was a pity.
Peter20x4 Characters lcd module blueProduct works well, I use it with the recommended I2C interface, read the PDF file and it works like this!
Stéphane BOUEMAX7219 4x Dot matrix modulePerfect, quick to build and works immediately if you find the right code ( Opencircuit only provides scripts for very advanced projects)