Interesting emulator speed issue

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This topic contains 2 replies, has 2 voices, and was last updated by Profile photo of billtheunjust billtheunjust 2 years, 7 months ago.

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  • #29701
    Profile photo of bitsentry

    So here’s an interesting speed related issue that I’ve been troubleshooting for a while. Well at least its interesting to

    First, what Im working with:

    RPi Model A
    128/128 split
    Turbo OC config from raspi-config (very stable)
    RetroPie v2.2 (headless)

    Also the controller is a custom built HID based bluetooth SNES controller using Adafruit’s excellent EZ Key Bluefruit hardware. More about the project here:

    Mine works perfectly and Im very pleased with it.

    Anyways, on to the issue.

    I’ve noticed that when I use the start button on my controller, which is mapped via HID to the spacebar, the emulation speeds up by 2x and causes severe audio fragmentation and crackling. This only seems to affect the 8 and 16 bit console emulators and not MAME, NEOGEO or PSX.

    This is annoying because when I start a ROM, the Start button is used in navigating the games main menus. Sometimes you can use a face button to navigate so its avoidable, but in games that require pressing Start (aka spacebar) in the main menu it will immediately trigger acceleration of the emulation by 2x or sometimes 4x with very bad audio. Then when gameplay starts its super fast. This can be avoided by simply restarting the ROM and not using the start (space) button and it will play then normally. I’ve duplicated this behavior with the Atari2600, NES, SNES and Genesis emulators. In the case of Atari, its unavoidable.

    I checked the usual config files but must be missing something. Any ideas why pressing the spacebar in a game menu would cause emulation speed up?

    Profile photo of bitsentry

    Nevermind. I figured it out.

    In /opt/retropie/configs/all/retroarch.cfg

    you must set:

    input_toggle_fast_forward = space

    to something else. I used use an arbitrary key that my HID controller isnt using.


    Profile photo of billtheunjust

    I’ve been trying to figure out why my genesis had bee speeding up. This helps a lot. Is there a way to disable the fast forward key all together? The line is already commented but the key still functions…

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