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#397 DOSBox Boot.COM can't reboot.


Hi there!,
I recently started playing around with DOSBox, and I tried to run one of the OSes called MikeOS through the program that comes with DOSBox,
But it doesn't reboot the DOSBox x86 Emulator, Instead it does all sorts of weird things,
The code I try out is :
mov al,0xFE
out 0x64,al
Is it a bug?


  • Peter Veenstra
    Peter Veenstra

    the boot command doesn't "reboot" dosbox. It loads in a diskimage (the parameter you provide) and tries to bring the emulation state (register wise) to the state, as if the PC is booting.

    I am not sure what you are trying to do. We provide the boot command so that people can run BOOTER games.

    I am not sure what you are trying to do with a port write to port 64.
    But we don't support rebooting through that. You might wonder why, the answer is pretty simple: Games don't need it.
    So it is a missing feature, which is not really missing as games don't use it.

    for port 64 we handle:
    0xae, 0xad, 0xd0 and 0xd1

    Personally I don't consider it a bug, as it is clearly our design to not support rebooting through port 64.

    I hope this clears up the matter a bit.

  • sid

    Thanks my doubts are cleared,
    So the isn't meant for booting operating systems (although it can) and neither for rebooting.... since it's meant for running games.
    What the code does is, it sends 0xFE to 0x64 port, which would reboot a PC.
    Thanks Again!

    Last edit: sid 2013-11-06