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I'm not sure if I'm on the right exchange here but if not then let me know! Worth trying anyway.

I'm in the process of making a logic circuit to display a number, for example, 15711862 - it has to be that length anyway. I've had to make my own decoder and I'm stuck with the outputs and which gates to use, would I use an AND gate, OR gate, etc. as well as the wiring, how do I determine which letters would connect to which gate, to then connect to the pin of the 7-segment display (I'll add a picture below).

Like I said, I'm not sure if this is the right exchange to ask on and if it's not then let me know and I'll delete the question, but I'm quite confused right now! Any questions please ask below!

current logic circuit

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    \$\begingroup\$ What you need is what's called a "BCD t0 7 segment decoder", which isn't what you've shown. Neither is the display you've shown a 7 segment display, since segment "g" is missing and you'll only be able to display "1" and "7". Also, if you want to display more than one digit, you'll need as many decoders as you have digits and a means to drive each the inputs separately, or a multiplexing/latching/shift register scheme of some kind. Study this data sheet for a clue. \$\endgroup\$ – EM Fields Nov 25 '15 at 20:12
  • \$\begingroup\$ The circuit you have shown is a one-of-8 decoder. It's not clear what relation you think it might have to the function you describe. \$\endgroup\$ – Edward Nov 25 '15 at 20:18
  • \$\begingroup\$ Let's say you want to display from 0 to 9 on the display; if you are using BCD or binary as input to the decoder; then you need more than 3 bits as inputs ( 0-7 correspond to 3 binary digits). How do you intend to feed the input? \$\endgroup\$ – ammar.cma Nov 25 '15 at 20:20
  • \$\begingroup\$ +1 @EMFields You were faster than Usain bolt :) \$\endgroup\$ – ammar.cma Nov 25 '15 at 20:21
  • \$\begingroup\$ @ammar.cma: Thanks! :) After reading it over again, it sounds pretty much like an answer, so I'll post it as such also. \$\endgroup\$ – EM Fields Nov 25 '15 at 20:38
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What you need is what's called a "BCD t0 7 segment decoder", which isn't what you've shown. Neither is the display you've shown a 7 segment display, since it only has 7 pins. Also, if you want to display more than one digit, you'll need as many decoders as you have digits and a means to drive each the inputs separately, or a multiplexing/latching/shift register scheme of some kind. Study this data sheet for a clue.

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  • \$\begingroup\$ As the symbol on the right of the schematic has 7 inputs, I bet it is a 7-segment display just showing up a zero at the moment. \$\endgroup\$ – Martin Zabel Nov 25 '15 at 21:30
  • \$\begingroup\$ @MartinZabel: Nice catch! :) Point taken and my answer edited, but if it's a seven-segment display it needs at least 8 pins. \$\endgroup\$ – EM Fields Nov 26 '15 at 8:34

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