Need some logic gate help please

Thread Starter

cl10Greg

Joined Jan 28, 2010
67
Hello,
I have 10 branches of LED's that are wired in parallel with a witch to each branch to turn that branch on or off. What I am having trouble with is making a logic circuit to detect how many of these switches are on and off. It is plausible to have the logic submit the number of switches in binary but it cannot exceed 4 inputs to my PICAXE Microcrontroller. See what I want to do is have a counter count how many branches are lit up and display this information to a dual 7 segment display. I was working hours last night to try and figure out a combination of gates to fulfill this but I ran into a wall and now I am stuck and looking for any help possible. So please, anything that you can give me would be great! The LED branches are at 5V and 20mA each. The switches are just momentary normally open switches that are being held down until the object is removed above it (so in theory it is counting how many objects are left).
 
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