Re: 286 BIOS detecting 1.44Mb floppy drive as a 1.2Mb

Posted on 2016-01-09, 14:19

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I don't think there *is* a way to autodetect what type of floppy drive is connected (you can detect if a drive is present or not, but that's it). I've not seen it on any of my systems, and I wouldn't know how the floppy interface would even make it physically possible to detect. IDE is different, …

---

Re: How to make my PC speaker emulation support PCM audio?

Posted on 2016-01-09, 09:56

by

by Scali

in PC Emulation

in PC Emulation

Perhaps a better place for this is to put it in the PIT-simuation? You need to simulate the PIT at full 1.19 MHz accuracy anyway, which I suppose you trigger for every instruction you emulate, to check for timer interrupts or whatnot. You could just make it update the PC speaker buffer in there. …

---

Re: How to make my PC speaker emulation support PCM audio?

Posted on 2016-01-08, 14:30

by

by Scali

in PC Emulation

in PC Emulation

You don't have to run the emulation function at 1.19 MHz. You just have to generate a signal of 1.19 MHz. Which implies that the emulation function needs to process multiple samples at a time. This shouldn't be too difficult, since the PIT only generates a 0 or a 1, and you know from the count-value …

---

Re: How to make my PC speaker emulation support PCM audio?

Posted on 2016-01-08, 14:13

by

by Scali

in PC Emulation

in PC Emulation

PWM can be done on a PC speaker by using the single-shot timer mode on channel 2. So if you see channel 2 on the 8253 being set to single-shot, you should assume that your PC speaker simulation needs to go into 'PWM' mode. The PWM works as follows: In single-shot mode, the signal to the PC speaker …

---

Re: What are some early (pre-quake) 3D (not 2.5d) dos/windows games? (List?)

Posted on 2016-01-08, 13:11

by

by Scali

in Milliways

in Milliways

Reading Scali's post caused me to get the intro music stuck in my head, despite him not talking about GPU actually. ;) I don't know Grand Prix Unlimited, but I do know the earlier Grand Prix Circuit by Accolade. And I got that awesome C64 soundtrack in my head when I read that :) https://youtu.be …

---

Re: Enhanced support for Vista/7/8's Desktop Window Manager

Posted on 2016-01-07, 15:11

by

by Scali

in DOSBox Development

in DOSBox Development

I think this is more a case of using Direct3D9Ex, and using D3DSWAPEFFECT_FLIPEX and D3DPRESENT_FORCEIMMEDIATE flag on Present(). This allows vsync'ed windowed D3D applications (as if they were exclusive fullscreen and pageflipping), and works on Windows 7 and up.

---

Re: What are some early (pre-quake) 3D (not 2.5d) dos/windows games? (List?)

Posted on 2016-01-07, 14:07

by

by Scali

in Milliways

in Milliways

MicroProse Formula One Grand Prix from 1992 also had a very nice 3d engine for its day: https://en.wikipedia.org/wiki/Formula_One_Grand_Prix_(video_game) It's amazing that it was basically developed by a single person, Geoff Crammond. His work was groundbreaking in terms of simulation in games. He …

---

Re: Is this possible? (( Installing dos over ethernet to another computer that has boot ethernet option on it ))

Posted on 2016-01-07, 08:50

by

by Scali

in Milliways

in Milliways

I know my university did that with Windows 9x back in the day, on the library computers. They would just receive a fresh OS image everytime they booted, via PXE network boot. It requires two things: 1) A computer with a network card that has a PXE-compatible boot rom (these ROMs are optional, and …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-06, 21:04

by

by Scali

in PC Emulation

in PC Emulation

I see from the docs that it compiles with TP7, but is that object pascal? Well, it's an object-oriented form of Pascal. It's slightly different from Delphi though. Trixter (MobyGamer) or I can probably answer any questions you have regarding development. Trixter designed and wrote MONOTONE, and I …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-06, 09:42

by

by Scali

in PC Emulation

in PC Emulation

Does MONOTONE also support CMS on old soundblasters ? Not yet. Currently it supports PC Speaker, OPL2 and SN76489 (PCjr/Tandy). Adding CMS should not be very difficult though, since MONOTONE has a modular object-oriented design. You just need to implement a few procedures to add support for a new …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-06, 08:00

by

by Scali

in PC Emulation

in PC Emulation

How volume register affects output PCM value is known bit-accurately. After that, yes, there will be DAC, and who knows what in analog domain after it (maybe DAC filter, maybe mixer on SB and compatible cards, maybe speaker amplifier chip, etc..) Yea, that's what I mean. OPL2/3 themselves are more …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-05, 22:41

by

by Scali

in PC Emulation

in PC Emulation

Due to the logarithmic nature of the 6-bit volume register, playing back linear PCM sounds pretty awful. Which does gives ideas how to do it better :) The same goes for SN76489, it has a 4-bit logarithmic-like volume scale. It is best to have some empirical measurements of the volume levels, …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-05, 20:10

by

by Scali

in PC Emulation

in PC Emulation

I've played a few games (mostly from Silmarils but also Wizardry 7 from Sir-Tech) that somehow used OPL2 as a DAC for playing digitized sounds. This isn't supported well in DOSBox. Yes, there is some trick to setting up just the right waveform at just the right frequency so you effectively get a 0 …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-05, 08:01

by

by Scali

in PC Emulation

in PC Emulation

SquallStrife wrote: All fascinating stuff though, are the MON files from the demo available somewhere? Yes, they are included on Github: https://github.com/MobyGamer/MONOTONE See SWINGIN1.MON and NO_ROADS.MON.

---

Re: Purpose of switching video mode without clearing video memory?

Posted on 2016-01-04, 13:30

by

by Scali

in PC Emulation

in PC Emulation

This feature was only available on EGA and higher, so probably not a lot of 8088 software that would use it. The speed is indeed one reason to do this. Eg, you generally have a music routine that runs once every frame, so at about 60 Hz. Switching screenmode with clear takes more than 1 frame on …

---

Re: 8088 MPH: We Break All Your Emulators

Posted on 2016-01-04, 08:53

by

by Scali

in PC Emulation

in PC Emulation

Scali, what program was the Swinging Waste tune originally composed in? https://soundcloud.com/phoenix-dc5/swinging-waste-multi-channel-version <-- is that the original, or is the MONOTONE composition the original, and the former is "based on" the latter? If the above composition is available in …

---

Re: Questions about Cyrix made CPU's & their rebranded chips

Posted on 2016-01-01, 13:54

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I would just like to add that I once had an IBM 'Blue Lightning' 486DX2-80 CPU for Socket 3, which was a rebadged Cyrix Cx486 (earlier IBM 'Blue Lightning' 486DLC models were made for 386SX systems, and were not based on Cyrix, despite both using the 'DLC' name). It seems IBM also sold rebadged …

---

Re: 286/386 tech demo?

Posted on 2015-12-29, 20:36

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

Triton's Crystal Dream will run on a 286, and Crystal Dream 2 will run on a 386. I recall Majic 12 also doing some nice 386 stuff. Then there's UltraForce's Vectordemo, which is fine on a 286. And some of the Cascada productions should also run nicely on a 386 at least. Oh, and Renaissance is also …

---

Re: What are your favorite games from a musical perspective?

Posted on 2015-12-28, 20:54

by

by Scali

in Marvin \ General Old Hardware

in Marvin \ General Old Hardware

I love SID music. Last Ninja, Hawkeye, Tetris, to name a few. But for a more modern game... the original Need For Speed has some of the best music ever.

---

Re: DOSBox-X notice: If microsoft pulls this stunt, I will be dropping Windows support

Posted on 2015-12-28, 18:25

by

by Scali

in DOSBox Development

in DOSBox Development

I think you mean 'would be', rather than 'is', because Microsoft has not actually 'pulled' said 'stunt'.

---