Known tweaks needed to run programs under dosemu

1.1. Millenium game fails to detect Sound Blaster, unless the SB IRQ is 5

Solution: set $_sb_irq=(5). Fortunately this is a default setting, so in most cases you won't care.

1.2. Millenium game crashes when entering space combat

Solution: to the file 2200gx.exe apply the following patch:

    000030B2: AA 47

2.1. Wrong colors in video clips.

Solution: to file nfs.exe apply the following patch:

    000607E6: 00 08

2.2. Hangs or glitches in video clips.

Solution: to file nfs.exe apply the following patch:

    000B8E5A: 78 EB
    000B8E72: 78 EB

2.3. Installer crashes or unstable.

Solution: to file infsd.exe apply the following patch:

    0002873E: 7C EB

3.1. Goblins halts at startup with "Divide Error" message

Solution: apply the following patch to gobega.exe:

    00004A19: F7 90
    00004A1A: F3 90

4.1. Game freezes or crashes shortly after start.

Solution: set

    $_umb_f0 = (off)

4.2. Sound is crackling.

Solution: set

    $_dos_up = (off)

5.1. Timer is too fast during race

see here for details

Solution: for hi-res mode, apply the following patch to carma.exe:

    00083549: 89 83
    0008354A: C5 E8
    0008354B: 29 04
    0008354C: F5 90
    0008354D: 89 90
    0008354E: 2D A3

For low-res mode, apply the following patch to carma.exe:

    00083549: 89 83
    0008354A: C5 E8
    0008354B: 29 02
    0008354C: F5 90
    0008354D: 89 90
    0008354E: 2D A3

Unfortunately the timer is still a bit unstable, and runs as slower as faster you drive your car. To completely disable the timer, apply the following patch to carma.exe:

    00083549: 89 83
    0008354A: C5 E8
    0008354B: 29 00
    0008354C: F5 90
    0008354D: 89 90
    0008354E: 2D A3

6.1. Game freezes at start.

Solution: apply the following patch to runflat.exe:

    000130FF: 75 90
    00013100: F7 90
    00013110: 75 90
    00013111: F6 90
    00013112: D1 90
    00013113: E9 90

7.1. Game slows down unbearably after some playing.

Solution: update to v1.1 of the game or apply the following patch to prince.exe:

    00016549: CF CB

8.1. Cosmo's Cosmic Adventure doesn't start

Solution: Unpack the cosmo1.exe which is packed with LZEXE. Then apply the following patch:

    00011F8F: 75 90
    00011F90: F9 90

9.1. Long start-up delay (like half a minute)

No solution yet.

9.2. Black screen and hang after choosing the table.

Solution: A few driver files needs to be patched. Or just patch the one that you selected in a sound setup.

Apply the following patch to sb16.sdr:

    00002007: F7 90
    00002008: F3 90

Apply the following patch to sbpro.sdr:

    000020A4: F7 90
    000020A5: F3 90

Apply the following patch to sb20.sdr:

    0000206B: F7 90
    0000206C: F3 90

Apply the following patch to sblaster.sdr:

    00001F25: F7 90
    00001F26: F3 90

9.3. Game doesn't see the Fx keys that should start the game.

No solution yet, the game is unplayable.

10.1. Hang trying to play the MIDI file embedded in document.

Apply the following patch to vmp.com:

    00002C4B: 72 90
    00002C4C: 0D 90
    00002C5B: 01 00

11.1. dosemu crashes after a few minutes of work.

Looking at lexicon code, the crash seems intentional. Probably some kind of a copy protection. Apply the following patch to lexicon.exe:

    0000ED9C: 74 EB
    00011DAE: 74 EB

12.1. Game doesn't start, just returns to command prompt.

Test Drive 2 only works from drives up to F:. In most dosemu2 setups, these drive letters are occupied. Solution is to copy the game to C:.

13.1. Game is too slow.

Solution: set

    $_timer_tweaks = (on)

14.1. Game crashes on intro screen.

Solution: set

    $_timer_tweaks = (on)

15.1. Hangs on start.

Solution: set

    $_dos_up = (off)