A bit of point to point goodness :)


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  1. #1
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    Default A bit of point to point goodness :)

    Hi Guys,
    I just spent a harrowing two days building and test software for a joystick recorder/player to cheat at games

    Some advice interfacing to the computer would be appreciated.
    The retro joysticks are just switches that ground the respective pins,
    but I think a device like this would typically have some buffering for the outputs rather than a pic sinking directly.
    Transistors. logic, bilateral switches?


    This is the I2C bus addressing done:



    It works!


    Cheers, Art.

  2. #2
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    Default Re: A bit of point to point goodness :)

    Display board:

  3. #3
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    Default Re: A bit of point to point goodness :)

    Now we’re getting somewhere a greater than 7 hour player/recorder at 0.1 second sample resolution.
    There is more physical EEPROM that I’m using yet also, so I think I can sample much faster.

    I was surprised that at 20MHz, DT’s Elapsed time (real timer overflow interrupt) and I2C read/write works fine together.
    I have a flag watching for I2C error, and it’s not displaying unless I sabotage the hardware.


  4. #4
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    Default Re: A bit of point to point goodness :)

    LOL

    You just built the thingy that I warned a game dev about. I told them users can now "relatively" easily access devices to cheat in the time trial mode; racing alone on the race track.

    Saving wheel and pedal settings just takes a bit more space, but essentially it's the same thing.

    Cool device. I was wondering why you needed so much external memory.

    Robert

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    Default Re: A bit of point to point goodness :)

    I still do have to save coin 1 and player 1 buttons. If the bot doesn’t start the game itself it won’t be synced to the game.

    The current program is saving a byte ten times per second, and provides a little over 7 hours recording,
    but I would like to improve that resolution to 100 times per second, which will require a few more chips.

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    Default Re: A bit of point to point goodness :)

    What if you use another medium; SD card would be perfect.

    Robert

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    Default Re: A bit of point to point goodness :)

    How about using a sort of sample compression?
    Instead of storing the state at a fixed interval have a 24bit 10, 50 or 100Hz tick counter running. Whenever something changes state you store the counter value and the state.

    If the state is 16 bits each record will be 5 bytes total.
    Even at 100Hz resolution the 24bit tick counter allows for close to two days of recording before overflowing.

    Nice proto build!

    /Henrik.

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    Default Re: A bit of point to point goodness :)

    Thanks
    I did think of both ways, either time stamp and data, or continuous data.
    I suppose I like the idea of a memory timer as well though

    SD card I remember reading it’s easy to access byte by byte raw mode, but I never looked into it.
    yes I probably could have gone nuts, and these EEPROMs are samples,
    but if you buy them they aren’t cheap considering what you pay per byte.

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    Default Re: A bit of point to point goodness :)

    ...and done


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