(This may belong in Sound, not sure?)
Hi all,

I've got this Toshiba T6600C luggable computer, which is a 486DX2-66 with a VGA color LCD, onboard SCSI (for the optional, internal 5.25" CD-ROM drive) and a WSS in the form of an AD1848KP and a YMF202-M.

It has two full-length ISA slots, into which I've installed a 3om 3c509 and a MK1869 XTREME. I've added a MT32-Pi (McCake) to the WaveBlaster header on the XTREME. For shits and giggles I've wired the output of the XTREME to the internal CD-audio connector so I can use the built-in stereo speakers.

All of the tests have been performed both with the ESS MPU-401 and with the PCMIDI addon.

Most things work as expected; my config is as follows:

• I load WSSXLAT on boot just to enable the CD-ROM audio input; I assign I/O 240 and IRQ 3 to the SB emulation
  • Warm-booting afterwards leaves the audio input enabled, so subsequent boots don't need to load the driver
  • All of the tests have been run with onboard WSS *disabled* and without the driver; no change
• I have the onboard SCSI disabled (or, in some tests, configured to IRQ 10 to be out of the way)
• The 3Com takes up IRQ 15 and an I/O port far away from any sound (no secondary HDC here)
• I use UNISOUND to init the XTREME:
  • ESS config: BLASTER=A20 I5 D1 H1 P330 F0 T4
    (H1 makes some things work that don't otherwise. Other permutations tested; see below.)
  • InterWave: ULTRASND=230,5,5,11,11
  • I have matching IW.INI and call IWINIT to make OpenCubicPlayer detect the RAM on the IW

What works:

• DOTT, Monkey1 (talkies; with SB+MT32)
• Various demos and music players
• Wolf3D
• Larry 1 (AGI) and 2-3 (SCI0, right?), with AdLib, SB or MT-32 modes
• Larry 5, SQ4 with AdLib or SB modes
• DOSMid using MT-32

What does not work:

• Larry 5, SQ4 with any variant of MT-32 (plain MT-32, MT-32+Sound Blaster)
• Presumably other Sierra games of the "fancy mouse pointer" generation (SCI1+)

What has been tested:

• Booting with and without the WSS enabled
• Various I/O port configs for the ESS
• ESS (..P330..) and PCMIDI (..P0 U0..) MPU-401
• EMM386, JEMM, HIMEM only
• ESS and PCMIDI on different ports/IRQs (330/300, 2/3)
• No mouse plugged in (tested because the BIOS does funky things when the PS/2 mouse is plugged in, like making XTIDE 2/386 builds fail - only the most basic XTIDE version works)
• no mouse driver
• 3com card removed
• CPU cache disabled
• Variations on the BLASTER setting: FM synth enabled/disabled, high DMA set/unset, P0 U0 (when PCMIDI installed)

Symptom: Hard wedge a split second after the mouse pointer shows up. Hard-reset required.
When the MPU-401 (whichever variant) is not on port 330, the games start fine. AdLib and SB-only drivers work fine. I have a display hooked up to the MT32-PI; it never changes so it never sends any SysRq messages.

I can't find any updates to the MT32 drivers anywhere, except some that need to be applied with some special executable that I cannot run - and those are to enable SB2/Pro-type MIDI output, not to fix this. And since I tested with disabled cache, this is not a "fast computer" problem either. And let me tell you, this machine is already dog slow even with cache enabled... it doesn't even have L2 cache!)

All this tells me that the problem happens when the game speaks to port 330 (or IRQ 2?), but *only if hardware actually exists there*. I am at a complete loss here, so any suggestions welcome.

Thanks for reading! :)