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I had this awesome idea to use a calculator as an atari 2600 because the atari has a ridiculously simple controller that I think can be easily emulated with a microcontroller. I don't know how to explain it in a way that makes more sense, but i am confident that it will work. I made a mock-up already, just using normal tactile switches, just to confirm that i have the pinout of the DB9 port on the Atari correct.

Next i have to get a hold of a raspberry pi (or an arduino, I'm not quite sure which one will be more useful) And set it up to accept input from a program on the CE (written in C) through the usb port, and then the pi/arduino will push the correct voltage through the right pin of the controller cord.

I bet that makes no sense because i don't know how to explain it, but i promise that it makes much more sense inside my head
I have figured out more of what I am going to do!
I am going to use relays (mosy likely solid state) to simulate the button inside the joystick being pressed (because of how the Atari detects buttons being pressed) and the relays will be controlled by whatever I use to parse the data from the calculator program (which I still need to write)
Just kidding, I'm dumb, transistors will work way better than relays, and be less bulky, so that is good.
I should have the circuit design finalized today, and then i will start work on the calc side of things (I'll post the circuit once i design it, it should be really simple)
Fun fact you should use logic gates not transistors (even though that's really what they are)
logic gates made using transistors, lol

I just need something which, on any input, connects 2 pins
Okay, so I found out (from a cemetechian, either Tari or Runer) that 2 back to back MOSFET transistors is exactly what i need, so i purchased some, and i also got an arduino uno and a usb host shield for communicating with the calculator
That was me!

Driving J1 high will allow current to flow either way between J2 and J3. You need two back to back FETs because otherwise you'd still get current flow through the body diode when reverse-biased.

SLVA948 is a pretty good TI app note that discusses bidirectional power switches like you want.
Awesome! Thank you so much Tari! Your input was ridiculously helpful!!! <3
Quote:
20:05 <jacobly> it makes the calc act like a usb hid keyboard
20:06 <jacobly> the arduino just converts hid events to wire signals
I found some libraries and documentation for communicating with an hid keyboard through my specific USB host shield, so I will be reading that learning stuff!

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