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Retropie Coffee Table Concept, Help with wiring (brainstorming)



  • General Concept:
    Coffee table where a retropie permanently resides (RGB lights within the table). The table will have a stationary RGB trackball and 2 Aimtrak Light Guns, but each of the 4 players will have individual arcade control boxes that fit into the table where they connect to the table via USB (retropie) so there is the option to either play at the table or take them out and play on the couch. Each of the four RGB lit controllers would have an Ultimarc ServoStik 4 Way to 8 Way, 8 game buttons, start button, coin button, with turbo set and turbo clear buttons (RGB buttons where available, including joystick). The retropie will be displayed onto the room's TV via HDMI, and I will have a power plug for the table.

    My Question:
    Obviously the controllers will draw quite a bit of power. Do you have any suggestions or ideas for wiring such that I will only require a USB connection from the controllers to the table?
    I am thinking I will need the control wiring within each controller, then a powered USB hub within the table to power each of them. BUT, isn't the maximum power for USB 3.0 only 4.5-5 volts? The Servostik alone I believe requires that much power.
    Also this presents another issue, how will the stationary trackball be wired? On it's own controller?
    This would make 7 USB connections to the retropie (4 controllers, 1 trackball, and 2 light guns). Since not all of these devices (at max 4) will be in use simultaneously I don't think I need to worry about it, apart from finding appropriate USB splitters/hubs to make all these connections to the raspberry pie.

    Hopefully you have some ideas, for brainstorming at the very least. If you have any questions or need a better idea of the system, please do not hesitate to ask. Thanks guys!



  • @mrmarblz If you get a decent powered USB hub it should be able to supply full power to each port. If the ServoStik does then pull full power, you could split off the cable and add a second USB connector (wired for power only) to drive the rest of the controller? The downside is that each controller would then need 2x USB ports, so you might require an extra hub or two.



  • @mrmarblz The trackball will need an interface board. Some arcade trackballs are sold without that, so be sure you have a solution for it or add on the interface if you have that option. The controller board will accept the wires from the trackball and will connect to the Pi via USB and should appear as a mouse to the Pi. Same with each light gun. If your table is wired with AC power your USB hubs can be powered and plugged into AC inside the table, so you can add as many hubs as you need.

    If the Servostik is just a USB device, it gets 5 volts that way. The current draw would be as much as any gamepad plus maybe more while the server is engaged. Why would this be a problem

    I would definitely use a powered USB hub for all of these devices, as you don't want the power to come from the Pi's AC/DC adapter. You don't want the Pi to have power issues because of all of the peripherals attached, and powered hub(s) should take care of that.

    In order for the removable arcade controls to connect via USB, they will need to be wired internally to some kind of interface. There may be good choices for this, but a cheap option might be to hack four gamepad controllers and just wire your controls to the buttons etc.

    This is an ambitious project. Check out my 4 player cocktail system. Mine is a bit simpler, but I had different challenges. My only question for you is: Why, no spinners?



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