I made a small adapter from my motherboard's three pin "GND, 12V, GND" CPU fan header to a normal 2 pin fan header so I don't accidentally plug a modern 3 pin fan to it and send 12V tachometer pulses through ground:

I'm having issues with the sound in Wolfenstein 3D. Two sound blasters are putting out sound effects which are cut in half. Like a sliding door can be heard only a fraction of the complete effect.
The cards are CT1600 and CT3980, in a 286 16MHz with 5MB RAM.
Let's see what happens when I disable the music.
And get a heatsink for that EMU8K, that thing is getting hot...

PD2JK wrote on 2023-10-04, 20:10:

I'm having issues with the sound in Wolfenstein 3D. Two sound blasters are putting out sound effects which are cut in half. Like […]
Show full quote

I'm having issues with the sound in Wolfenstein 3D. Two sound blasters are putting out sound effects which are cut in half. Like a sliding door can be heard only a fraction of the complete effect.
The cards are CT1600 and CT3980, in a 286 16MHz with 5MB RAM.
Let's see what happens when I disable the music.
And get a heatsink for that EMU8K, that thing is getting hot...

It might be a fault with DMA if you're getting bad digital audio with 2 cards, especially on something as old as a 286. I had a similar experience with a 386 motherboard that used an 82c206 and it turned out to be the 74F245 bus transcievers seemed to have some conductive dirt under them, removing, cleaning and reinstalling fixed it: Re: What retro activity did you get up to today?

Today, a tragedy occurred:

This translucent orange plastic has now broken in so many different ways, it's more superglue than plastic now.

Thermalwrong wrote on 2023-10-04, 20:44:

This translucent orange plastic has now broken in so many different ways, it's more superglue than plastic now.

If you can get a 3D printed part as a replacement, you can print it orange to match. It won't be translucent, but it will still be an improvement.

Learning how to use XMS memory with C is what I did today.

Rav wrote on 2023-10-04, 21:55:

Learning how to use XMS memory with C is what I did today.

Give us the particulars and highlights of your journey.

Kahenraz wrote on 2023-10-03, 08:50:

BetaC wrote on 2023-10-03, 07:45:

Welp, after taking out my DOS system to eventually get back in to TIE Fighter I found out my SC-55’s screen has decided to die. I don’t even know where I could start for trying to fix it, or replace it. Music still plays without issue, and none of the caps look bad.

Luckily, you don't need the screen for any of the functionality for games. The only thing you'll want to know is how to do a hard reset between games if it's not resetting itself properly. You would have to do this with a screen regardless anyways.

Extra luckily, the issue seems to have cleared up. I think a capacitor is just slowly dying inside it, as leaving it plugged in for a few days instead of leaving it unplugged for a few months was the answer.

kant explain wrote on 2023-10-04, 23:18:

Rav wrote on 2023-10-04, 21:55:

Learning how to use XMS memory with C is what I did today.

Give us the particulars and highlights of your journey.

I made an application to configure the settings as I have an ACER 486 with basically no useful settings in the BIOS.
Doing some memory maneuver are required to change the cache mode from WB to WT as else it crash due to dirty bit not cleared in the tag chip. To make it simple, you want to fill the cache with unimportant data before the config change and after, to be sure the tag chip is consistent.

Edit : Of course I had to make a correction right after posting a screenshot... WS0 instead of 0WS.. 😂

I installed OpenBSD 5.1 i386 on my 486 DX50 tonight. It has 32MB FPM and a Cirrus Logic VLB card. This is after playing around with a very similar build in 86box for a while, trying to find the newest version of OpenBSD that will boot fine from floppy and detects the CD drive properly and reads the disc properly - 5.1 worked the best in my case. 5.2 still sees the CD drive but can't read the contents, 6.3 boots but the floppy kernel doesn't see the CD drive at all. I've read online that 6.5 should work, and possibly up to 6.7 (19 May 2020) - after which the compiler target for i386 platforms was changed from i486 to i586 to support a newer LLVM version. So no more modern OpenBSD on 486s unfortunately.

I might be able to get a later version running by copying the newer install sets over to the CF card (using CF temporarily for testing), then doing a manual upgrade. Or by using a separate CF IDE adapter on the other IDE channel to host newer install sets.

It's currently still generating RSA keys. :D

Update: Logged into my 486 over SSH and can ping the net. :)

1# uname -a
2OpenBSD 486DX50.local 5.1 GENERIC#160 i386
3# sysctl hw.model
4hw.model=Intel 486DX (486-class)
5# ping -c 1 google.com
6PING google.com (209.85.146.100): 56 data bytes
764 bytes from 209.85.146.100: icmp_seq=0 ttl=52 time=41.017 ms
8--- google.com ping statistics ---
91 packets transmitted, 1 packets received, 0.0% packet loss
10round-trip min/avg/max/std-dev = 41.017/41.017/41.017/0.000 ms

While saving some old driver cds i came across this instruction.

I tried to put my win98 cd in my floppy drive and aquired detailed knowledge in partitioning because i had to cut the cd in small pieces to get it to fit.

Umm.. It does not tell you to insert the CD into the floppy drive though?

appiah4 wrote on 2023-10-05, 13:16:

Umm.. It does not tell you to insert the CD into the floppy drive though?

But its not funny if i just put the floppy marked as "cd" in the floppy drive.

DerBaum wrote on 2023-10-05, 12:58:

2023-10-05 13.52.02.jpg
While saving some old driver cds i came across this instruction.

I tried to put my win98 cd in my floppy drive and aquired detailed knowledge in partitioning because i had to cut the cd in small pieces to get it to fit.

I knew you were joking but that's "Start Disk for Windows 98 CD," neither "disc" nor "of." Furthermore, not every system back then supported CD bootup, and not every optical drive was compatible with the generic driver by Oak Technology bundled in the official Win98 Boot Disk, so a customized startup disk might be required for an OEM system.

ok. i get it. my joke was bad. in my language disk and disc are not that far apart.

DerBaum wrote on 2023-10-05, 13:27:

ok. i get it. my joke was bad. in my language disk and disc are not that far apart.

They are interchangeable but disk is usually reserved for floppy and hard/fixed drives while disc refers to optical ones.

Rav wrote on 2023-10-05, 01:16:

I made an application to configure the settings as I have an ACER 486 with basically no useful settings in the BIOS. Doing some […]
Show full quote

kant explain wrote on 2023-10-04, 23:18:

Rav wrote on 2023-10-04, 21:55:

Learning how to use XMS memory with C is what I did today.

Give us the particulars and highlights of your journey.

I made an application to configure the settings as I have an ACER 486 with basically no useful settings in the BIOS.
Doing some memory maneuver are required to change the cache mode from WB to WT as else it crash due to dirty bit not cleared in the tag chip. To make it simple, you want to fill the cache with unimportant data before the config change and after, to be sure the tag chip is consistent.

33.jpeg

Edit : Of course I had to make a correction right after posting a screenshot... WS0 instead of 0WS.. 😂

Not sure about early 5V chips, but later should flush cache on SMM register change events, so if you send it an SMM state change before, do the thing, then change SMM back after then cache should be consistent.

Desoldered 3 50V 10 and 4.7µF electrolytics from a 286 m/b. For the time being I replaced them with tantalums.

BitWrangler wrote on 2023-10-05, 14:29:

Rav wrote on 2023-10-05, 01:16:

I made an application to configure the settings as I have an ACER 486 with basically no useful settings in the BIOS. Doing some […]
Show full quote

kant explain wrote on 2023-10-04, 23:18:

Give us the particulars and highlights of your journey.

I made an application to configure the settings as I have an ACER 486 with basically no useful settings in the BIOS.
Doing some memory maneuver are required to change the cache mode from WB to WT as else it crash due to dirty bit not cleared in the tag chip. To make it simple, you want to fill the cache with unimportant data before the config change and after, to be sure the tag chip is consistent.

33.jpeg

Edit : Of course I had to make a correction right after posting a screenshot... WS0 instead of 0WS.. 😂

Not sure about early 5V chips, but later should flush cache on SMM register change events, so if you send it an SMM state change before, do the thing, then change SMM back after then cache should be consistent.

I think that apply only to the L1 cache.

I did use WBINVD instruction as it specifically do exactly that (on all 486). That instruction also send a command to the chipset so it can do the same with the L2 cache but most chipsets including the Ali M1429G I'm working on don't honor that and it's why I resolved to ram filling / moving / reading to hopefully evict all of that. Work fine on all DOS configuration I tested but it work like 1 times out of 10 if I do it from Windows (the thing probably switch tasks and so some windows chunks will still be dirty in the WB L2)

Turned on the Epson Stylus Color 440 I got at a thrift store to see if it'll power on and it does. I just need to find my cable and copy the drivers to the CF card or SD card since I don't have a CD drive for the laptops yet.

Kahenraz wrote on 2023-10-04, 21:31:

Thermalwrong wrote on 2023-10-04, 20:44:

This translucent orange plastic has now broken in so many different ways, it's more superglue than plastic now.

If you can get a 3D printed part as a replacement, you can print it orange to match. It won't be translucent, but it will still be an improvement.

they do have translucent filament. Wouldn't be exactly the same but could work.