Help! Don't know what circuit I need to solve this problem

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mercuryrising

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Hi everyone. I am a complete newbie to electronics and need some help with the following problem. I have 8 switches or inputs and 8 leds or output. I want to be able to press any or all switches from 0 to 7 in any sequence, for example I press switches 0 7 2 in that order and leds 0 7 2 light up in that order when I press on on a Go button 3 times, ie I press the Go button the first tome 0 lights up, hit it again 7 lights up etc. I also imagine Id need a clear button. Any ideas?
I have looked at encoder/decoder ADC circuits but am swamped by the information available. Im 17, give me a break! Do I need the inputs to be encoded in a binary address and then output to the corrosponding led? Help please, I'm confused!
 
You need a micro-controller, a PIC would do the job easily - doing it in hardware would be VERY complicated.
 
@Nigel
It appears an school question of home work for practice of hardware logic design.
He may well be able to purchase a PIC, but would not yet be able to write a program for it I fear !
He need to learn programing language, write...., get access to a programmer to be able to burn his hex file.
 

One way to do it [the GO button needs to be de-bounced, but no switches]:

The switches connect to an 8 input OR gate that increments a counter whose outputs supply memory addresses, so as the counter counts up the switch closures are stored in memory.
The memory has 8 data lines and 3 address lines.

Then, when the GO button is first pressed the counter is reset to zero, then the memory contents of the lowest address is clocked out.
The next press of the GO button clocks out the next address without doing a reset, and so on. The reset is done only on the first press.

You'll need some more gates, invertors, pull-up resistors and/or one-shots to take care of startup and for when the next sequence of switch closures begins.

Post your prelim schematic or programming steps and the results you see and we all can help you fill in the missing gates or commands.

If you use CMOS and buy parts from Hosfelt or Allelectronics and power it from several 1.5v cells stacked to make a 6v to 12v battery, probably $10 has you covered for all parts except the battery and a box.
 
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