Using the Alphanumeric display

This alphanumeric display is kind of interesting to work with.  It has 4 different segments that can be switched.  If you wanted to make a 3 on the left digit you would have to switch back and forth to get a 3.

Cathode 1 = low, 2=high, 3=high 4=high
Segments A, D = on

Then switch to

Cathode 1=high, 2=low, 3=high, 4=high
Segments A, B, C, D = on and the rest off.

See the schematic thumbnail below for more info:

Click on image to expand