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By charging the first capacitor up to Vcc, and then discharging it into a second cap that has an initial charge of 0v, they will both average out to a voltage equal to: [(Vcc-Ci)/2]+Ci (Ci being the initial charge on cap 2). The charge on both capacitors will now be 2.5v after the first switch transition if Vcc is 5v for example... charge cap 1 to Vcc again, then discharge it into cap 2 once more, and now the voltage will be 3.75v according to that equation, because C2's initial voltage increases, and gets exponentially closer to Vcc with each switching transition. That means, you can use a Schmitt trigger to sense a specific threshold voltage depending on what the voltage is on cap 2 after a certain number of switching transitions... thus; counting how many times you toggle the switch without using any flip flops! However, there is a limit as to how many times your able to toggle the switch with this method, before cap 2 approaches Vcc so closely that the difference gets so small it becomes practically impossible to measure any more.
1. Use the switches (but only one at a time) to set whether it triggers on 1,2,3, or 4th toggle... (they are placed in order with the top switch being count #4, and the bottom one representing count #1)
2. LED will illuminate only on the toggle count set by the switches, and will not light up if you toggle below or above set count.
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