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Does anyone else remember having to configure I/O, IRQ, DMA etc? As a kid I had no understanding of what these things were so I always tried random values until the sound worked without distortion.

The sound blaster also had a joystick port which back then was also used the emit MIDI signals. I installed a MIDI split cable on the joystick COM port and then configured sound in games to use the Roland Adlib MIDI mode. I hooked up my Yamaha PSR 730 Keyboard to my computer and got to enjoy much higher quality sounding music.

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> configure I/O, IRQ, DMA etc? As a kid I had no understanding of what these things were so I always tried random values until the sound worked without distortion

I got my start in the Win9x days. I cannot begin to describe how confusing it was (with no knowledge of PC computing history) to have sound working perfectly in Windows, only to start a game where sound would not work. Only to be greeted with a settings menu with hundreds of possible sound configuration options with no clue what to try to get sound work. If I actually got my start in the old 386 PC days, opening the case, reading the brand of sound card and looking at jumper settings would have been a start. But with some "ESS" sound chips not listed anywhere, no jumpers showing the settings, etc., it was a complete black box.

Didn't have internet access to go to and research computer problems in those days, and I had no technically knowledgeable friends... Windows Help system was of no help, and it could be a considerable time sink with its terrible search function finding tons of irrelevant hits. Game documentation rarely provided clues. The way forward at the time would have been to buy one of the many non-distinct books on computers available on store shelves.

I definitely remember SET BLASTER=A220 I5 D1 H5 in my autoexec.bat.

I somehow got away with never adding this in my autoexec.bat.

I don't remember much with regards to tweaking that stuff.. running memmaker.exe comes to mind. Also loading the CD driver in extended memory mode (MSCDEX.exe /E). Then there was himem.sys etc

I would really love to see a good blogpost on all these things so I can finally learn what all these things actually did -- back then it was just trial an error. All the tweaks I had to make to free up "conventional memory" despite having a lot of RAM.

That environment variable just was there for software to read and auto-config your card. If the jumpers were default it wasn't needed.

Most programs I remember just used it as a hint. There would usually be menu settings that were the definitive source.

It was more important for later jumperless PnP cards with a non-PnP BIOS.

Same here. Something around many fives.

The earliest Sound Blasters had IRQ7 as default. This conflicted with LPT1 so the default was changed to IRQ5. There are a few games like "Gods (1991)" and "Space Quest III (1989)" that have IRQ7 hardcoded, so for best compatibility with older games IRQ7 is needed.

Yes, "good" memories, in a bad way. If you had a "home" PC, adding a sound card was not a terrible issue, but once you had an "office" pc with with something like two serial ports, a printer and, God forbid ! a network card (obviously a ne2000 or a 3c509), free IRQs were somewhat of a scarce resource.

Absolutely, there were IRQ & DMA defaults that usually worked pretty well in my experience, and in my friend group everybody had memorized fallback combinations to try. You never knew when you'd suddenly need to change that stuff when visiting a friend's house.

It's funny you mention using your Yamaha keyboard for MIDI out. I did this with the SB Live back in the day, it had a pretty cool front I/O panel too. I remember playing Phantasmagoria this way and getting creeped out really fast. Probably didn't help that the music was coming from my keyboard which was in another part of the room.

IRQ 5, DMA 1--but I had to adjust my COM mouse to use a different IRQ.

Also, I had a highly tuned config.sys and autoexec.bat to get as much memory as I possibly could for King's Quest 3.

How did you learn to tune those? It was all trial and error for me. I'd love to see a blogpost about this so I can finally learn all the things that I should have done but didn't back in the day :)

It wasn't about "tuning", you simply needed to configure everything so there weren't any collisions, and this depended on whatever other expansion cards and ports you had in your PC, because there was a limited amount of IRQ channels (2, 5, 7, 10), DMA channels (0, 1, 3), and I/O addresses (0x220, 0x240, 0x260, 0x280) that expansion cards could use.

The original 8-bit cards could be configured through jumpers on the card, and the settings you put into autoexec.bat or individual setup programs for your games, simply had to match the hardware settings.

Later, plug'n'play meant that your PC's BIOS could auto-detect and auto-assign everything to avoid collisions, so you didn't have to bother with it.

The tuning part is to free up enough of the base 640k of RAM to allow certain games to even run.

Exactly, or else we'd get the dreaded message of having insufficient "conventional" memory. Tuning autoexec.bat and config.sys were necessary.

> Later, plug'n'play meant that your PC's BIOS could auto-detect and auto-assign everything to avoid collisions

which at the beginning was rather plug and pray.

Books.

I spent my allowance on computer books about MS-DOS and various programming languages, assembler, interrupts, how computers worked, etc, etc.

I was obsessed with learning every little program that was in that dos folder, and how to write batch files and properly tune the config.sys. Then windows hit and there were ini files to explore. Plus you could hack a lot of old dos games with binary file editors.

I was just so passionate about everything. I feel sorry that all of this is just handed to my kids now. They’ll never choose to do the deep dive unless something takes over their brain.

If my friend’s dad hadn’t taken me to their old 286 and ran “type command.com” to make a bunch of gibberish appear on the screen I have no idea where I would be today. I was hooked from that moment.

> Does anyone else remember having to configure I/O, IRQ, DMA etc?

I totally do. It wasn't fun but in the end, somehow, we always ended up configuring everything correctly!

I'm still cargo culting with Linux kernel parameters to fix various graphics and hardware issues.

Indeed, I remember looking for executable files in a game’s directory to find something other than the game itself, a “config.eve” or something, and running it to get some kind of text-based menu with unfamiliar conventions.

I have a feeling I had to set the IRQ to 5 on my machine, I also remember something being 220 but maybe I’m imagining that one. I remember doing it so many times it no longer made sense.

I remember seeing a friend (or a friend’s parent) set IRQ to 7 on their computer, that was a real event for me, first time I realized the other values were legitimate options too.

Older ISA Sound Blaster cards indeed have jumpers to configure I/O ports, IRQ lines, and DMA addresses for the hardware, and traditionally there was no reliable way to auto-detect conflicts with other hardware — such conflicts are a likely source of your distorted audio — so manual reconfiguration was frequently required.

Additionally, Sound Blaster-compatible software requires either manual or semi-automatic configuration via the BLASTER environment variable or application-specific configuration mechanisms to determine the hardware configuration.

Creative indeed repurposed a couple infrequently-used pins on its implementation of the IBM PC game port[1] to implement a MIDI interface; other vendors followed suit.

In addition to computer music applications, external MIDI modules — most notably, the Roland MT-32[2] and Sound Canvas SC-55[3] — were commonly supported by games of the era[4].

Today, all this can be easily emulated in both software[5] and first-party emulated hardware[6]. Additionally, Sound Canvas was the basis for the General MIDI standard, so it's also possible to wire up DOSBox MIDI to other GM-compliant synths for similar results (at least in [relatively] newer games with General MIDI support; attempting to emulate MT-32 via GM rarely works out well).

Source: personal experience, though "back in the day" I used a Roland SCC-1, which combined an SC-55-compatible synth and an MPU-401-compatible[7] MIDI interface on an ISA card. For most games, this configuration also required a separate sound card for non-music sound effects, but was otherwise convenient, slots permitting, as it required no external hardware.

[1] https://en.wikipedia.org/wiki/Game_port

[2] https://en.wikipedia.org/wiki/Roland_MT-32

[3] https://en.wikipedia.org/wiki/Roland_SC-55

[4] https://en.wikipedia.org/wiki/List_of_MT-32-compatible_compu...

[5] https://dosbox-x.com/wiki/Guide%3ASetting-up-MIDI-in-DOSBox%...

[6] https://id.roland.com/products/sound_canvas_for_ios/

[7] https://en.wikipedia.org/wiki/MPU-401

And for a dose of (in)sanity, check out LGR’s MIDI Mountain.

https://youtu.be/bQn3SyDh2Xo

Yes, and I never managed to configure this so that the Sound Blaster works with my handheld Genius scanner.

This brought back memories. I remember having to do that to get certain games to work.

You warped me right back to 11 years old, and I thank you for it.

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