Thanks Grahame,
How would something like that look like? I am not familiar enough with digital electronics to feel I can produce reliable results.
There is latch-enable and display-select to think of. Both of them must get the right signal at the same time.
Can you explain me why we need transistor T2?
Because, in the original description following with the circuit the author (C.H. Vithalani) explains that when S2 is closed, base of T2 is connected to GND and T2 starts conducting. (If you want the full text just let me know!)
I don't believe that at all! I believe that when S2 is open T2 is conducting and will stop when S2 is closed.
But then I don't understand the circuit anymore, and the datasheet is too advanced for me. I would need to study maybe a week in or so to understand, and in the meantime life goes on. I just want to finish this project, not using time to study electronics because my bosses don't pay me for such things.
So, therefore I would be grateful for someone who draws a simple circuit how to connect the 2 pairs of IR-LED and phototransister to a flip-flip, which in it's turn is connected to the LE and DS from IC2.
I already dug up some too simple designs. I would like to use some kind of stabilisation between photocell and flip-flop, in such a way there is no danger of statics, hysteresis or flip-flops that get stuck...
Greetings,
Ronald
Norway