Re: Win XP 32 or 64 bit?

Posted on 2023-12-04, 11:39

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I ran XP x64 at home and at work in period, I wanted to make the most of the Athlon 64s I had at the time. I seem to remember that once driver support was there it was really good. I don't remember any significant issues at the time. I wasn't much of a gamer by that stage though. Same here. As a …

---

Re: MartyPC

Posted on 2023-12-02, 18:57

by

by Scali

in PC Emulation

in PC Emulation

Hercules is of course possible but I don't know much about it and would need to do some research. Hercules is quite simple. It is basically an MDA card with 64k of memory and a hack to offer a graphics mode alongside the standard MDA functionality. Another feature is that the second 32k of memory …

---

Re: Creating 80186 Based System

Posted on 2023-12-02, 18:24

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

So ... SMC wasn't as obscure a chip maker as I thought. The Compucolor II used SMC chips.for graphics. Learning something new everyday. SMC, or Standard Microsystems Company was based in New York, and made various chips for microsystems (obviously) before finally specializing in networking. In the …

---

Re: Creating 80186 Based System

Posted on 2023-11-28, 11:31

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

(just as the V20 does) The NEC V20 (and its 8086-equivalent V30) seems to be what you'd actually want: You get a chip that is pin-compatible with the 8088 (or 8086), so it is a drop-in replacement in a standard PC/XT motherboard, and it gives you the added 186 instructionset and better performance. …

---

Re: Creating 80186 Based System

Posted on 2023-11-28, 07:51

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

DMA was used for memory refresh, floppy disk drive and hard disk drive. Yup, in theory you could do without, as the IBM PCjr demonstrates (as well as early Tandy 1000 models, where a DMA controller could be installed as part of a memory upgrade). It wouldn't be 100% PC-compatible, but you'd get …

---

Re: MartyPC

Posted on 2023-11-21, 15:13

by

by Scali

in PC Emulation

in PC Emulation

There appears to be a little bit of wiggle room, at least. MartyPC 0.1.3's DMA logic is actually off by one cycle - the effects still run, but it causes the 8088MPH CPU test to fail. Yes, there is a bit of 'self-correction', so to say. That is, technically the only time-critical operations are …

---

Re: Games with Adlib as an option for sound effects

Posted on 2023-11-21, 14:32

by

by Scali

in DOS

in DOS

jtchip wrote on 2023-11-21, 01:21: Links 386 Pro supports Adlib for PCM sound effects (it does not have music). Ah yes, good old RealSound. The original release of Links also has AdLib support, and it plays digital music during the title sequence.

---

Re: MartyPC

Posted on 2023-11-20, 19:06

by

by Scali

in PC Emulation

in PC Emulation

I assume the code is in the initialization of an effect that requires the system to be in 'lockstep'. In which case the DRAM refresh has to be synchronized on specific positions on each scanline. A frame is 19912 PIT ticks, and that is 262 scanlines, so you have 19912/262 = 76 PIT ticks per scanline …

---

Re: MartyPC

Posted on 2023-11-20, 13:58

by

by Scali

in PC Emulation

in PC Emulation

Then there's an interesting period where PIT channel timer #1 is set to '1'. I believe reenigne intended to quickly refresh all of DRAM before setting the counter to 19, but it seems that a value of 1 is too fast and actually disables DRAM refresh entirely Actually, I believe the reason for setting …

---

Re: Games with Adlib as an option for sound effects

Posted on 2023-11-14, 19:06

by

by Scali

in DOS

in DOS

ViTi95 wrote on 2023-11-14, 18:38: Tracker music is more CPU intensive than playing directly raw PCM music, so I ended up using raw PCM music for FastDoom. Unless GUS 😀

---

Re: Software rendering <> DirectDraw

Posted on 2023-11-14, 18:23

by

by Scali

in Marvin \ Software

in Marvin \ Software

dr.zeissler wrote on 2023-11-14, 18:02: overlooked that, thx scali! The original paper from 1978, where he calls it "Simulation of wrinkled surfaces": https://dl.acm.org/doi/10.1145/800248.507101

---

Re: Software rendering <> DirectDraw

Posted on 2023-11-14, 18:01

by

by Scali

in Marvin \ Software

in Marvin \ Software

As I showed with the earlier link, EMBM was developed by Jim Blinn in the 1970s.

---

Re: Software rendering <> DirectDraw

Posted on 2023-11-14, 17:27

by

by Scali

in Marvin \ Software

in Marvin \ Software

I knew that "dope" demo...it is GUS exclusive and it's also lowres 320x240/200 and yes it has some cool effects but the fukkin-demo looks way better and is one of the first ddraw-intros that got the look of pixelshader-stuff...the reflection on the liquid surface is the key here. The Funkkin-demo …

---

Re: Software rendering <> DirectDraw

Posted on 2023-11-14, 14:01

by

by Scali

in Marvin \ Software

in Marvin \ Software

That's cool! I didn't know this was possible so early! It's a trick known as environment mapping, or reflection mapping. You take a fixed image with a certain projection so that it can encode the environment (your 'environment map'), and by properly calculating the texture coordinates, you can …

---

Re: Software rendering <> DirectDraw

Posted on 2023-11-14, 13:49

by

by Scali

in Marvin \ Software

in Marvin \ Software

They are two different things. DirectDraw and Direct3D are APIs. More specifically, they are hardware abstraction layers (HALs). DirectDraw abstracts a simple 2D-oriented video card. Direct3D originally started life as an extension to DirectDraw for video cards that had 3D acceleration features ( …

---

Re: C64 fans seem to me more passionate and committed than retro-computing fans

Posted on 2023-11-08, 07:44

by

by Scali

in Milliways

in Milliways

Generation C64, that's me.

---

Re: MartyPC

Posted on 2023-11-07, 08:09

by

by Scali

in PC Emulation

in PC Emulation

Scali, I finally figured I could do a video of 8088MPH justice, so here it is (in 1440P): https://www.youtube.com/watch?v=Y6sS1cVKJCA Ooh yea, that looks very nice indeed! The composite colour seems accurate. And I like the CRT shader effect. I guess the only thing missing for perfect accuracy is …

---

Re: Games with Adlib as an option for sound effects

Posted on 2023-11-06, 10:41

by

by Scali

in DOS

in DOS

Does this take up all of the available "voices" of the FM synthesizer? Or is there a way to combine PCM sample output with FM music playback, albeit with fewer channels/voices? And are there any games that do that? You can use any individual FM channel as a pseudo-DAC in this way. However, …

---

Re: Games with Adlib as an option for sound effects

Posted on 2023-11-05, 21:14

by

by Scali

in DOS

in DOS

I haven't come across any. Tricking the Adlib to "sample" PCM audio via PWM through the OPL2/OPL3 would be quite a feat. Stereo .mods (with sampled audio, of course) through the Adlib? Wild! The method used is not PWM. Instead the oscillator is triggered and then stopped at its maximum amplitude, …

---

Re: C64 fans seem to me more passionate and committed than retro-computing fans

Posted on 2023-10-25, 14:28

by

by Scali

in Milliways

in Milliways

Yea, I second that. And I want to expand on that by going back to what was said earlier: The Commodore 64 may not have been the first of its kind, and it may not have been the best machine on the market. But it was cheap and easily available (where computers were usually only sold in special …

---