NES Core

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Don't Panic. Please wash hands.
  • That's a very good point. I did describe the keymapping in the video I posted to Patreon a couple of days ago (not paywalled) - and because I'd covered it there, I forgot to mention it anywhere else!

    The keys are:


    Gamepad 1:

    Start : Enter on PS/2, Return on C64, Play on CDTV pad

    Select : Right shift on PS/2, Right shift on C64, Volume up on CDTV pad

    Button A : Right ctrl on PS/2, Button B on CDTV pad (because NES pads have button B to the left of button A)

    Button B: Riight alt on PS/2, Button A on CDTV pad.


    Gamepad 2:

    Start : Caps lock PS/2, Run/Stop on C64, Play on CDTV pad

    Select : Left shift on PS/2, Left shift on C64, Volume up on CDTV pad

    Button A : Left ctrl on PS/2, Button B on CDTV pad.

    Button B: Left alt on PS/2, Button A on CDTV pad.


    The play and volume up buttons on the CDTV pad are routed to gamepad 1 or 2 depending on the position of the mouse/joy switch.


    The left-arrow key, top left of the C64 keyboard, the power button on the CDTV pad, the F12 key on the PS/2 keyboard, and the leftmost button on the Chameleon will all toggle the menu.

  • In PAL mode the picture is missing the bottom part on my 32 inch LCD TV. Same goes for the latest Amiga AGA core. However, on my BenQ BL702A the whole pictures shows. At least on the Amiga AGA core.


    Anything that can be done about this?

  • Well if it happens with two unrelated cores that doesn't bode well. How much is missing? Does the TV give any clue as to what mode it thinks its displaying? (There isn't a standard mode that looks anything like scandoubled PAL, so the TV's probably guessing, incorrectly, that it's receiving 720x400.)

  • Well if it happens with two unrelated cores that doesn't bode well. How much is missing? Does the TV give any clue as to what mode it thinks its displaying? (There isn't a standard mode that looks anything like scandoubled PAL, so the TV's probably guessing, incorrectly, that it's receiving 720x400.)

    It's missing enough where quite a bit of the graphics is not showing. Sounds very plausible that it's guessing 720x400 instead of 720x576. Probably 176 pixels missing. Strange thing is I don't think this happened with an older Amiga AGA core I was using. I still have the older core in my other TC64 V2. Will test it and confirm.


    Picture shows up correctly on the older AGA core (832AA0). So you must have changed something in the later core/cores that makes this happen on this TV. And the NES core must be using whatever you changed.

  • When I push down the joystick, it sometimes registers as the select button. This issue does not occur with the cursor keys. I'm using a Chameleon V1 with the docking station and a joystick in port 1.

  • When I push down the joystick, it sometimes registers as the select button. This issue does not occur with the cursor keys. I'm using a Chameleon V1 with the docking station and a joystick in port 1.

    Thanks for the report - I'll look into it. Could you try the "Swap joysticks" menu item, and tell me whether port 2 on the docking station behaves the same way, please?

  • Port 2 works as expected. The issue is only on port 1.


    I also noticed some minor bugs in the menu:

    - previously loaded games are listed as "Loading..." instead of the file name until you scroll the list.

    - menus scroll beyond the last entry.


    Is it possible to save the settings?

  • OK thanks for testing. This turned out to be the classic "joystick in port 1" interferes with keyboard" problem, which apparently affects the docking station, too. I've added fixes to the standard Chameleon docking-station and joy_keyboard components which should solve this - and fixed the two menu glitches, too. I'll release an updated core soon.

  • Thanks Alastair.

    The NES core has been running pretty well on my TC64V1 so far. I've already tested one game. ;-)

    I have just successfully loaded the FDS bios and was surprised that the file extension ".fds" is not recognized when I want to load a gamerom. Which file extension is expected by the core?

  • OK, here's an update ...

    So the FDS files are displayed normally in the FDS folder as long as the NES core has been loaded. NES games then run, FDS games do not. If I now load the FDS BIOS, a Nintendo screen appears. Now the FDS files in the FDS folder are no longer displayed. Is this an error?

  • OK, here's an update ...

    So the FDS files are displayed normally in the FDS folder as long as the NES core has been loaded. NES games then run, FDS games do not. If I now load the FDS BIOS, a Nintendo screen appears. Now the FDS files in the FDS folder are no longer displayed. Is this an error?

    It might be - I will investigate.


    However, note that the menu remains in the file selector when you load something - and the BIOS file selector is different from the ROM file selector.

    So what might be happening is that you're selecting "Load FDS BIOS", entering the BIOS file selector (which only shows .bin files), then when you return to the menu you're still in the BIOS selector so it's still only showing .bin files.

    Try going to "Back" to return to the toplevel menu, and see if you have more luck.


    Either way, it needs to be fixed - but I don't know yet whether it's a bug or just a user-experience fault.

  • After the FDS-BIOS has been loaded, the blue "Nintendo ... now loading" screen appears. If I select the menu with F12 and then "back", I can now also see the .fds files with the load function. I can start it, but then land back on the blue "Nintendo ... now loading" screen without actually loading the game. Must the file names have a certain length?

  • After the FDS-BIOS has been loaded, the blue "Nintendo ... now loading" screen appears. If I select the menu with F12 and then "back", I can now also see the .fds files with the load function. I can start it, but then land back on the blue "Nintendo ... now loading" screen without actually loading the game. Must the file names have a certain length?

    To be honest, I've actually no idea how the FDS stuff is supposed to work!


    What I've done for this core is essentially created a wrapper which allows (some) MiST cores to run nearly unmodified on the Chameleon. There might be a bug in the ROM loading which prevents the FDS file working, or it might be something else.


    When I have a moment I'll track down some FDS files and the BIOS, and see how it works on the MiST.

  • I've tried the FDS BIOS on both MiST and MiSTer tonight, and I can't get either to do anything useful. From what I can gather, there's a required patch for the BIOS. MiSTer applies it on the fly, MiST - and thus the Chameleon port - doesn't.


    Even on MiSTer - where the patch is applied on the fly - I haven't yet succeeded in loading an FDS file.