It's a 2 by 3 grid. There are not that many combinations.
I would recommend just doing it by hand in your favourite image editor, such as Paint, GIMP or Photoshop. First make a template for "a circle" and a grid you can use for each character so they are all aligned. Copy and paste circles into the right places. Then create straight lines. In GIMP for example you can easily create straight lines by clicking, then holding shift and clicking again. In paint there is a line button I believe.
When you have your characters, you can copy and paste them.
If you feel adventerous, you can create a grammar to be used by turtle graphics. It is probably more work, but maybe more fun.