MiSTer FPGA Forum

Posted: **Sat Jan 08, 2022 6:11 pm**

Hi,

As the subject says, I'm trying to get the MT-32 music going on Frederik Pohl's Gateway (from Archive.org) with a mt32-pi HAT (via the user port).

The ao486 README states that the MIDI interface can be found at 330h and IRQ 9, while MANUAL.TXT included with the game says:

Code: Select all

BLASTER Causes music and RealSound sound effects to be played through
        a Sound Blaster card, if present.  You may set the IRQ number
        and I/O address for your Sound Blaster card by typing:
        GATE BLASTER  <irq number>  <i/o address>.

MT32    Causes music to be played on a Roland MT-32 (or compatible)
        sound module, if present.  You may set the IRQ number and
        I/O address for your MIDI interface by typing:
        GATE MT32  <irq number> <i/o address>.

However, starting the game with the corresponding parameters:

Code: Select all

GATE.EXE BLASTER 5 220 MT32 9 330

Results in an error message: "Unable to access the MT32 on IRQ channel 9."

Starting the game with just the BLASTER option works as expected, and other games see the mt32-pi just fine.

Digging through the GitHub issue tracker, I found this comment from Sorgelig which, if I understood correctly, implies that IRQ 2 would be redirected to IRQ 9 under the bonnet. Sadly, setting the MT-32 IRQ to 2 seemed to have no effect.

Has anyone gotten MT-32 support to work with the game? Thanks!

Posted: **Mon Jan 10, 2022 6:45 pm**

I found a thread over at vogons that may provide insight.

https://www.vogons.org/viewtopic.php?t=37884

TLDR, Gateway doesn't play nice if the MT-32 isn't connected to a real Roland MPU-401 MIDI interface.

Posted: **Sat Jan 15, 2022 10:24 am**

HarborSeal wrote: ↑Mon Jan 10, 2022 6:45 pm TLDR, Gateway doesn't play nice if the MT-32 isn't connected to a real Roland MPU-401 MIDI interface.

Thanks. The ao486 README says that the MIDI port supports both "dumb and fake-smart modes", but I guess the core's fake-smart mode isn't compatible enough for Gateway's MT-32 implementation. It'd be great if a hack could be added for Gateway like the one described in the thread you linked to, but I don't know whether that'd be feasible or not.

Posted: **Thu Jan 27, 2022 7:19 pm**

I have the music playing on my MT32-pi using softmpu, and it's working fine apart from some slight timing issues with the first track.

The soundblaster is set up to use irq 5, and then softmpu is loaded with the following arguments:
SOFTMPU /MPU:330 /SB:220 /IRQ:5

and finally gateway like this:
GATE MT32 5

Posted: **Thu Jan 27, 2022 8:27 pm**

SoftMPU did indeed do the trick, thanks!

MiSTer FPGA Forum

Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT

Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT

Re: Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT

Re: Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT

Re: Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT

Re: Getting MT-32 music to work on Frederik Pohl's Gateway with a mt32-pi HAT