TM1640 8x8 Matrix LED Shield driver

This is a LED matrix display driver for the WeMos Matrix LED Shield.

Support is included in the TM1640 (About Modules) module, using the Graphics library.

var g = require("TM1640").connect({din: NodeMCU.D7, clk: NodeMCU.D5}, function() {
  g.drawLine(0, 0, g.getWidth() - 1, g.getHeight() - 1);
  g.setContrast(2); // a value between `0` lowest and `7` highest intensity.
  g.flip();
});