Counting 0-3

Hi Timko, This is a very elegant circuit. Nice construction. If you don't mind, I have a question and one very minor suggestion. The minor suggestion first. At pins A & B of the decoder... it appears as though the two are shorted. Nothing more than the Simulator placement of a node. I discovered that if you move the inverter (at the left) one grid space to the right, the shorted appearance resolves. // The big question now. Obviously this circuit works well. My education of digital circuits is rather lacking, so I must ask... What is the function of the analog circuitry? I watched the op-amps and they don't seem to be doing much. Since each op-amp output is at 5 volts, I thought that perhaps they were providing some sort of biasing, but I can't really tell. Could you help me/(us) understand this, please? Thanks for your offering.