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I'm working on a Matrix screen. To keep the caracters on the screen without giving the posibility to let other caracters be displayed on the same time did I make a blocker circuit. I does work quite good. However, sinds I put a binary converter in it to make te signals from my keyboard smaller does it give two karacters while i pres only 1 button. For example, if I press the F there will be a F and a B on the same screen. But I made a converter that should work properly. Does anyone know why this happens?

Hi,
Why do you need to filter one letter at a time on your matrix? If I were designing such circuit, I would have code of character as an input. The circuit then just simply translate the code to set of signal to LEDs. If the input code is not a symbol that you recognize than you can just display nothing.
As another note to your design, you have many repetitions. For example on your Blocker circuit, you have whole bunch of flip-flops. If you create such flip-flop as a separate circuit, it will make much easier to debug and understand the blocker.
Another example is on the Converter circuit you have whole bunch of And gates all of them are just equivalent to one And gate with 7 or 8 inputs. Your Dot Control is just Or gate with many inputs.
You can perform some verification of your circuit by playing with Edit menu and selecting all wires, free wires and floating symbols. That lets you verify that all connections are correct. For example on your Blocker circuit, you have some floating symbols and free wires.
Hope this will help you to build your circuit.
Eugene

So you mean that I just have to make only one blocker circuit for a certian code and not a character? In some way it makes sense...
"The circuit then just simply translate the code to set of signal to LEDs." So you mean making the code go straight into the dotcontrol instead of converting them first?
I understand the blocker, but it looks like it get a false pulse to me.
This big amount of And and Or gates is because I learned in the little bit of digital stuff only to work with 2 entrance gates and so I did use it here to. But thanks for mentioning it.
I know of those floting symboles. It helped me knowing how it goes. I will look at it.

I mean that you do not need to have any blocker circuit. Your display just need to get code of symbol and show it.

I'm finished whit what I was trying to make. It might be havy on your pc but it looks nice to me.
The best is to loot at 45%.

Very nice!