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Annotation of uae/docs/FAQ, revision 1.1

1.1     ! root        1: Some Frequently Asked Questions. Please read this carefully if you have
        !             2: problems.
        !             3: 
        !             4: Q: Will there be a Windows version?
        !             5: A: I'll never write a non-commercial program for DOS/Windows again. I hate
        !             6:    having to reboot after mistakes.
        !             7:    I included the DOS port because a) a DOS version can achieve similar
        !             8:    speeds as the Linux/SVGA version b) it didn't messify too much of the code,
        !             9:    and c) more people told me they would port it to DOS and I wanted to save
        !            10:    them the effort. I don't think a Windows port will fit in as cleanly as the
        !            11:    DOS port, nor do I think it can be efficient. If you want, you can try to 
        !            12:    prove me wrong, but I will be very reluctant to include Windows code. The
        !            13:    same goes for code to support a bazillion soundcards for DOS, or similar
        !            14:    nightmares.
        !            15: 
        !            16: Q: Is it possible to read Amiga disks with a PC?
        !            17: A: Ask that in comp.emulators.misc :-) The answer is: NO! Unless you invent
        !            18:    and build some extra hardware yourself, which no one appears to have done
        !            19:    yet.
        !            20: 
        !            21: Q: Couldn't I attach an Amiga floppy drive to the PC somehow, and use that to 
        !            22:    read Amiga disks?
        !            23: A: You can attach Amiga (low-density) drives to the PC, because they are
        !            24:    completely identical to PC drives. This won't help you, because the problem
        !            25:    is not the drive, but the PC floppy controller. You have to live with it.
        !            26: 
        !            27: Q: But...
        !            28: A: No way.
        !            29: 
        !            30: Q: The linker says "final link failed: Bad value"
        !            31: A: Please upgrade your Linux installation with the latest files that you find 
        !            32:    on sunsite.unc.edu:pub/Linux/GCC, but read the release_* files carefully
        !            33:    before you install anything. It seems that a linker bug causes this
        !            34:    problem. The package you need is binutils-2.6.0.2 or better.
        !            35: 
        !            36: Q: The assembler chokes with something about "operand doesn't match size".
        !            37: A: I don't know yet whether it's a bug in GCC, UAE or in the latest binutils.
        !            38:    Try downgrading to binutils-2.6 (binutils-2.6.0.14 for Linux users).
        !            39: 
        !            40: Q: What about sound emulation in the DOS version?
        !            41: A: Recent versions of DOS UAE support sound.
        !            42: 
        !            43: Q: How can I change diskfiles?
        !            44: A: Read the "Installation" section in the README to find out what you need to
        !            45:    use the X GUI.
        !            46: 
        !            47: Q: The "configure" script does not find Tcl/Tk, but I have it installed!
        !            48: A: The script checks for an executable called "wish4.0". There is currently
        !            49:    no better test. Unfortunately, this executable is not always present,
        !            50:    even though Tk 4.0 is installed. If that is the case, find the "wish"
        !            51:    executable, go into the directory where you found it and type 
        !            52:    "ln -s wish wish4.0" (provided you have write rights in that directory,
        !            53:    i.e. you are super-user). Then go back to the UAE directory, remove the
        !            54:    file config.cache and rerun "configure". That should do the trick.
        !            55: 
        !            56: Q: Is it possible to read Amiga harddisks with a PC?
        !            57: A: Yes. Linux 2.0 has an Amiga filesystem that can reportedly read Amiga
        !            58:    OFS/FFS harddisks. Since Linux 2.0.7, it's also possible to mount .adf 
        !            59:    files. Just say (for example)
        !            60:      mount wb13.adf /mnt -t affs -o loop
        !            61:    to mount the file wb13.adf at /mnt. You'll need to configure the loop
        !            62:    device and the affs filesystem into the kernel, and you'll need to say
        !            63:    yes to the question about experimental drivers at the beginning of the
        !            64:    kernel configuration. You'll also need a reasonably new version of the
        !            65:    mount program.
        !            66: 
        !            67: Q: When UAE starts up, it says "Illegal instruction: 4e7b". Why?
        !            68: A: That's normal, it's just the Kickstart CPU type test.
        !            69: 
        !            70: Q: When UAE starts up, it says "Illegal instruction: 00f8" (many times). Why?
        !            71: A: That's because your Kickstart ROM was compiled for the 68020.
        !            72: 
        !            73: Q: When UAE loads <insert your favourite game> it says "Non-standard sync".
        !            74: A: Your favourite game is copy-protected. There are ways to transfer such
        !            75:    disks, but it's complicated and I won't help you because it would be much
        !            76:    too time-consuming to figure out all sorts of copy-protection schemes.
        !            77:    I hope there will be a general solution some day, but for now you're
        !            78:    unlucky.
        !            79: 
        !            80: Q: While it compiles, it says "xxx illegals generated" or "16 mismatches".
        !            81:    Is this a problem?
        !            82: A: No. I can use this information to tell whether there is a problem, and
        !            83:    there isn't.
        !            84: 
        !            85: Q: Why is there a blank area on the left side of the screen?
        !            86: A: The Amiga can display graphics there, but usually doesn't because this
        !            87:    would disable some sprites. The area is only used by some overscan demos.
        !            88:    Normal screens are off-center. I'm not going to do anything about that.
        !            89:    If you can't stand it, you can try to use 320x200 resolution, which will
        !            90:    attempt to center the screen. This is near impossible to get right for 
        !            91:    every program. If your screen doesn't fit in 320x200, use 800x600.
        !            92: 
        !            93: Q: Benchmark program <insert your favourite benchmark> gives weird results.
        !            94: A: Amiga programs run by the emulator think the Amiga timers can be used to
        !            95:    measure real time. But in UAE, they only measure "emulation time". Sysinfo,
        !            96:    for example, gives the same results on all machines. So don't run
        !            97:    benchmarks to test the emulator speed.
        !            98:    Some benchmarks also use tight loops of DIV or MUL instructinos to measure
        !            99:    CPU speed, and in "emulation time" these instructions take as much time
        !           100:    as any other instructions, and you'll get much too high values.
        !           101: 
        !           102: Q: Wasn't this called the Unusable Amiga Emulator?
        !           103: A: Yes. But no one thought the name was very fitting anymore, though. It was
        !           104:    only really appropriate for v0.1, which couldn't even boot.
        !           105: 
        !           106: Q: Sometimes, after UAE exits, there is no autorepeat for the keys!
        !           107: A: Do "xset r on" (happens only in X, apparently mainly on Solaris boxes.
        !           108:    Dunno why.).
        !           109: 
        !           110: Q: Would it be possible to speed it up by emulating the CPU native on, say,
        !           111:    a 68k Mac?
        !           112: A: I doubt it. UAE needs to be able to interrupt the CPU emulation anytime to
        !           113:    perform tasks necessary for emulating the hardware.
        !           114: 
        !           115: Q: Would it be possible to speed it up by using graphics accelerator boards
        !           116:    for example by using the blitter in S3 chips?
        !           117: A: I doubt it. If the S3 blitter worked in similar way as the Amiga blitter,
        !           118:    which is unlikely, it might work; but you'd have to keep all Amiga chip
        !           119:    RAM in the graphics memory and that would most likely make everything
        !           120:    painfully slow.
        !           121: 
        !           122: Q: Wouldn't it be better to translate MC68000 code to x86 assembly?
        !           123: A: Yes. It would also be slightly more difficult.
        !           124: 
        !           125: Q: Emulating all the hardware is a bad idea. Why don't you just emulate the
        !           126:    OS? After all, that's what makes the Amiga the Amiga.
        !           127: A: Short answer: I disagree. 
        !           128:    Long answer: The OS is half of what makes the Amiga the Amiga. It is a very
        !           129:    nice OS, and there are some features that I miss in any other OS, but it is
        !           130:    also severely lacking in terms of (for example) memory protection and
        !           131:    filesystem performance. 
        !           132:    The other thing that made the Amiga special back in the 1980s is the custom 
        !           133:    chip architecture. If you look into old (1985) computer magazines, you will 
        !           134:    find that the capabilites of the Amiga OS are only mentioned as a side
        !           135:    note, because people were not aware that it was revolutionary for a home 
        !           136:    computer. They were aware, though, that the Amiga could display 4096 colors 
        !           137:    at the same time and that it had a blitter and a copper that could do all
        !           138:    sorts of stuff, like bouncing balls for instance. And I think it was the
        !           139:    superiority of the hardware that made the Amiga a success.
        !           140:    I see UAE as a program that is similar to C64 emulators: it allows you to
        !           141:    run some old games and other programs that you can't replace with better
        !           142:    equivalents on the PC. As such, it can already be used to run non-action
        !           143:    games (like Monkey Island or Bard's Tale) at a satisfactory speed. Faster
        !           144:    CPUs will eventually make it possible to run action games, just like faster
        !           145:    CPUs have made it possible to emulate a C64 at full speed on a PC. UAE is 
        !           146:    not (primarily) meant for the Amiga PowerUser who is running high quality
        !           147:    applications on his A4000 with a 68060 board, but for people like me who
        !           148:    switched from an A500 to the PC a few years ago because they wanted to make
        !           149:    money by developing software.
        !           150:    Besides, emulating an OS is far more difficult IMHO. Especially if the
        !           151:    platform you are emulating it on is completely different than the platform
        !           152:    that is being emulated. You'd have to mess with endianness conversions and
        !           153:    other nightmares. The AmigaOS wasn't designed with portability in mind 
        !           154:    either.
        !           155: 
        !           156: Q: How can I transfer non-DOS disks that are used by many demos?
        !           157: A: With transdisk. The fact that they are unreadable by AmigaDOS does not
        !           158:    mean they are unreadble by transdisk. Only copy-protected disks can't be
        !           159:    transferred that way.

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