Early blackjack counting systems development
During the second part of XX century, Dr. Keith Taft began developing the first kept secret blackjack computer, and soon, he had started using a computer in the Nevada casinos to play blackjack. Nevada state couldn’t provide any law to prevent him from this. He went on to develop dozens of concealable computers and other electronic devices over the next two decades, ever smaller and more powerful.
Here’s how it worked
In the toe of each shoe there were two “switches”, or buttons - one above each big toe and one beneath - for a total of four switches. Each switch conveyed a different code to the computer, which was a small epoxy-encased device that was strapped to the calf beneath the trousers. The computer itself was about the size of a pack of cigarettes, but thinner. By using a series of toe taps, kind of like Morse code, the player could relay to the computer everything it needed to know in order to make a decision in a blackjack game: which cards had already been dealt, what cards the player held, and the dealer’s upcard.
This computer were connected with player with buzzes and taps on the sole of the player’s foot. It was not easy to use one of these devices. It essentially entailed learning to “type” with your big toes. Even once you had memorized the codes, inputting them via the toe switches was a chore. It took weeks or even months of practice to get to the point where you could use the device at casino-dealing speed without foot cramps stopping you.