Re: Sound Blaster 2.0 project & IRQ from OPL2

Posted on 2018-06-22, 11:03

by

by Jo22

in Marvin \ Sound

in Marvin \ Sound

Ok, looks hardcore DIY, but the DAC prototype is finally assembled and connected to OPL2/ISA part. Will do the tests today.. Looks good! :) By the way, I didn't mean to be disrespectful when I sayed it looks like that. Rather in reverse. Back in time, in Germany, small series and prototypes were …

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Re: Configure SB16 (Vibra) to mono-output via software possible?

Posted on 2018-06-22, 10:48

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

My PM7300 has only one mono-speaker. My PC-Card has a Vibra16 Soundblaster stereo. Sometimes Music or SFX does not sound right because of the mono-speaker. You can also use a simple Y-cable for that purpose. The commercially available types do produce shorts, though. While they do work with most …

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Re: Hardware for Win3.11

Posted on 2018-06-21, 19:06

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

The slowest machine I've run Windows 3.1 on is a 12MHz 286 with 1MB RAM & 640x480 VGA graphics. That's good for running about 1 thing at a time very slowly. You don't want to go that low though, so the suggestions of 386 & above are good. As a long time 286 user, I had a similar experience. Though …

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Re: Mac-only or Mac-best Games

Posted on 2018-06-21, 11:13

by

by Jo22

in Marvin \ Software

in Marvin \ Software

^I heard the Mac community is working on a modified OS 9 that works on unsupported models (or was it in reverse, editing the firmware ?) Last time I checked, they apparently got it to work -or rather to boot up to the welcome screen- on the G4-based Mac Minis and some G5 machines.

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Re: Did AC adapters / Power supply change a lot in the last 20 years?

Posted on 2018-06-21, 10:57

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

True. The transformer-based brick PSUs came in different types, also. a) AC models (required the device to have a built-in rectifier or voltage regulator. Examples: Euopean NES, SNES) b) DC models, unregulated (cheap and were common for simple devices. Speakers, toys, etc. Voltage was higher without …

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Re: FlashFloppy, an open source firmware for Gotek drives

Posted on 2018-06-21, 10:30

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I already have aurdino cables around (cables with male/female dupont connectors) but the real reason is "Getting the proper pin headers is more elegant", of course :lol: Haha, I see. I do understand that, I prefered the proper way, too, when I flashed mine! :) Besides, some of them also required …

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Re: Which ROM image of SeaBIOS is the one for the 80386-compatible PCs?

Posted on 2018-06-20, 21:19

by

by Jo22

in PC Emulation

in PC Emulation

I think the same. The only exceptions to this,- which comes to mind right now-, are early PC, XT or AT motherboards. They pre-dated what we now commonly consider "chip sets" and were often based on dedicated logic chips, which usually all came from different manufacturers, but were more or less the …

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Re: Art of CGA

Posted on 2018-06-20, 03:24

by

by Jo22

in Marvin \ Video

in Marvin \ Video

For example, back in time. clone cards and Mono/Color combo cards were seemingly more common in Germany than IBM CGA cards, I believe. Not sure about the UK, though or why it was that way at all (if it was, my memories are a bit sketchy). Our first family PC was an Amstrad PC1512 which had a clone …

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Re: ISA Graphics Card Dead, any chance of resurrection?

Posted on 2018-06-19, 19:34

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Ah, I see. I was thinking of a high-level approach. Just like some "compatibles" in the 1980s where emulating CGA on the BIOS level, without the underlying Motorola 6845 hardware. Just the graphics modes, the bit planes/video memory layout and some dummy registers. Emulating the whole CRTC in real …

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Re: ISA Graphics Card Dead, any chance of resurrection?

Posted on 2018-06-19, 19:14

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

We need someone to design a nice VGA core on a FPGA... Absolutely! Though an ATMega-based VGA or CGA/Hercules card would be a feat, too. Even if they would do initially support the basic video modes only, it would be fine. Edit: "Fine" in the senses of a start. In the past years, a lot of VGA/CGA …

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Re: ISA Graphics Card Dead, any chance of resurrection?

Posted on 2018-06-19, 18:57

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Beware: I have little knowledge of the inner workings of graphics cards, but in general, the 74LS series ICs can (still) be found for little money in the average electronics shop or radio store "around the corner". If one of these ICs is defective, it could explain the odd behavior (partially, at …

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Re: FlashFloppy, an open source firmware for Gotek drives

Posted on 2018-06-19, 16:41

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Are we talking about the pins required for the TTL cables to make contact with the Gotek PCB ? If so, if you can't find/get them locally: You can borrow them from broken PC motherboards. They are on the front side of these boards sometimes, where the cables for speaker/power/led/etc connect to. …

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Re: Which Is a Faster Drive SCSI or IDE

Posted on 2018-06-19, 15:52

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

SCSI CD-ROM drive that came with PAS16 was probably double (might be quad) speed. So pretty slow. Yes, you're right. The CD-ROM kit came with a CDR-H93MV (CDR-H93), a 2x drive. See https://www.vogons.org/viewtopic.php?p=566088#p566088 (As far as I know, it had its issues with multi-session discs.. …

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Re: Mac-only or Mac-best Games

Posted on 2018-06-19, 12:59

by

by Jo22

in Marvin \ Software

in Marvin \ Software

Interesting thread, thanks for it. :) I'm fairly new to the Mac, but I've read a lot about it in the Windows 3.1 days. For me, System 6/7 were its counterpart and I always had been curious about the platform. I guess it was also because of films like Hackers or The Net that made it really …

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Re: Sound Blaster 2.0 project & IRQ from OPL2

Posted on 2018-06-18, 21:46

by

by Jo22

in Marvin \ Sound

in Marvin \ Sound

I think it would be the other way around. DMA via the LPT will be a bit difficult, especially on older machines. Direct DMA transfers to audio hardware via the parallel port would be just about impossible; the parallel port and ISA bus are quite different. The DMA functionality would have to be …

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Re: Art of CGA

Posted on 2018-06-18, 18:25

by

by Jo22

in Marvin \ Video

in Marvin \ Video

I have actually played around with this, and there are two problems. One is that the CGA card only has 16kB of VRAM, which is only enough to cover half of a 640x200x4 screen. This by itself would be a huge problem - you could have a reduced viewport rectangle or use CRTC trickery to make a non- …

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Re: OPL3LPT : OPL3 FM Synthesis on parallel port

Posted on 2018-06-18, 17:09

by

by Jo22

in Marvin \ Sound

in Marvin \ Sound

If the PCB gets a little bit smaller in a future revision, it'll even fit inside a stock DB25 shell. 😀

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Re: A beast of a computer - Compaq Deskpro 84'

Posted on 2018-06-18, 15:16

by

by Jo22

in Marvin \ System Specs

in Marvin \ System Specs

and parking the heads on the MFM drive then disconnecting it completely, after turning the machine off[..] I could be wrong, but not all park programs are the same. Some were intended for a specifc fixed disk model. However, I recall that PC-Tools Deluxe included a park program, too. Maybe that one …

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Re: How do I screen record with Windows 95?

Posted on 2018-06-18, 11:04

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

"How do I screen record with Windows 95?" Use a VHS camcorder. It's period-correct. :cool: (Seriously, though: Some S3 graphics cards had CVBS/S-Video out. Since you're using a laptop, there are also VGA to CVBS/S-Video boxes. You can then grab these signals with those cheap VHS to PC adapters from …

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Re: Compatiblity of DRAM IC

Posted on 2018-06-18, 10:34

by

by Jo22

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Hm. EMS cards can be had easily. Lo Tech, Sergey Malinov and others have designed them. Yes, I heard positive feedback about these. I *think* the smartness of these new cards relies within the driver. AST Rampage and others went far beyond to what final EMS 4.0 provided (EEMS). Advanced EMS …

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