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Trixter's latest magic... Holy how-in-the-hell!!!???

Very nicely done! Speaking of Doc Brown and Calvin Klein, a time machine back to 1982 to run this on a 5150 in front of a middle aged wool blend suited IBM exec would be a priceless reaction to behold.

Anyone going to Assembly later in the year? Sadly my 2600 demo won't be ready in time. Demo compos have faded in popularity over the past 2 decades in favor of LAN gaming. But many like Revision are still a nice spectacle to witness in-person. i highly recommend it; even if just once.
 
cr1901 said:
So Trixter, is the reason this demo breaks all emulators due to the fact that none of them emulate the 8088 prefetch queue bus cycle behavior properly?
Click to expand...

That is the reason why the demo will probably crash on emulators.
But even if it doesn't crash, some effects will not look/sound right, because they rely on cycle-exactness of the CPU, the CRTC and video memory wait states.
And then there is probably no emulator out there that will correctly simulate the high-colour tweakmodes with NTSC artifacting.

This demo will also not work entirely correctly on most clones, because just having a 4.77 MHz 8088 and a CGA-compatible adapter is no guarantee for cycle-exactness with the real IBM PC/XT and CGA. We have also found that the artifact colours on clone CGA (ATi Small Wonder/Paradise PVC4) tend to be different from real CGA.
 
So this in fact does what any C64-demo (or other fixed platform) does: it uses/abuses the HW that is available, and will not work correctly if the HW is not 100% correct. Nice!
I really like the demo. Too bad I don't have a proper IBM...
 
cr1901 said:
So Trixter, is the reason this demo breaks all emulators due to the fact that none of them emulate the 8088 prefetch queue bus cycle behavior properly?
Click to expand...

Yes, specifically the end credits part (with the 4 channel music) does not work on DOSBox for exactly this reason. In the source code for this part (which I will be releasing soon) there is a build flag to make a version that does work with DOSBox (which was useful for debugging) by moving the "to be patched" instruction above the instruction that does the patching. Unfortunately on real hardware the routine takes a couple of cycles longer to execute with this change, preventing the PC speaker update from happening at the right time.
 
I would love to be a fly on the wall of that wool suited ibm execs office. I agree, How in the holy hell did you achieve that. If IBM had you 30 years ago in their graphics department. Commodore, Amiga, Atari, all of them would be out of business....
 
k2x4b524[ said:
I would love to be a fly on the wall of that wool suited ibm execs office. I agree, How in the holy hell did you achieve that. If IBM had you 30 years ago in their graphics department. Commodore, Amiga, Atari, all of them would be out of business....
Click to expand...

Well, not really. Commodore and Atari would say "well done!" for bringing a $1000+ 16-bit IBM PC up to the graphical and sound capabilities of their $99 8-bit systems. :)
 
LOL

Found the software:p
http://www.pouet.net/prod_nfo.php?which=65371

KLIK on the header tekst "8088 MPH" (tekst in Bleu) and directed to the download site.
Klik row 3 kolom 2 on DOWNLOAD.

Downloaded and put on a 3,5 FFD
Than in an old 486 with real 360k FFD
Copied just the files - not the image.
Put it in my 5150 also took out the CGA card from the XT 5160 (program did NOT Run on the XT !)

Dos load 5.0
Run 8088MPH.EXE

My 5150 just has 2x 360k FFD's -265k of MEM and a put the CGA (Hercules) card in it.
Took the 5153 CGA IBM Monitor.
And up and running that Demo.

It was not as great as the You-Tube video, but still lot off FUN.

8088mph-001.jpg

8088mph-002.jpg
 
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Very, very stunning demo. Makes me wonder how games would have looked back then, had the programmers known such tricks.

The only thing I don't quite get is the intro text. Why would anyone think an IBM PC from 1981 would crush a C64 in a demo compo? The C64 didn't even exist in 1981. It's later hardware and also made for games. Souldn't it say: "C64 would crush IBM in a compo, right?"
 
Looking at your screen-shots I'd say you are running an RGBI-monitor, whereas the demo requires composite video connection to an NTSC monitor.
 
reenigne said:
What was the symptom when you tried to run it on the XT? It should have worked there - we used XTs to develop and capture it!
Click to expand...

Yes, to be exact, the capture on YouTube is also the one that was shown at Revision. We captured it on the spot from my PC/XT.
My configuration was like this:
- IBM PC/XT 5160 from 1987
- Old style IBM CGA card
- Serial card
- Floppy controller
- 5.25" 360k FD drive
- Harddisk controller
- Seagate ST225 HDD
- 640k of memory
- Sound Blaster Pro 2.0
- IBM PC DOS 3.30 (note that the demo does not work with 2.x versions of DOS)

The HDD and serial port were only for convenience during development, and were not actually used during the demo.
The Sound Blaster Pro 2.0 was used for the capture, because it has a PC speaker connection on its mixer. This allowed us to tap the signal from the motherboard, and pass it through the SB Pro mixer, then out to a 3.5" jack, so we could connect it to the capture device, and adjust the levels for recording.
The SB Pro itself was not actually used during the demo of course, and in fact, no SB software was installed on my machine whatsoever. Not even a SET BLASTER-statement in my autoexec.bat.
 
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Timo W. said:
The only thing I don't quite get is the intro text. Why would anyone think an IBM PC from 1981 would crush a C64 in a demo compo?
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Because it was a machine that was priced much higher, and totally dwarfs the C64 on paper, based on the specs (4.77 MHz vs 0.985 MHz, 640K vs 64k).
Besides, most people probably think a 'PC' is a lot more powerful, because they mainly know 286+ systems with VGA and soundcard, which indeed perform a LOT better than what we have.
 
A PC in 1981 didn't have 640k (due to BIOS limitations could only be expanded to 544kb). The motherboard took between 16kb and 64kb, and you could add more with expansion cards. I guess 64kb to 128kb would have been fairly typical in 1981. C64 could also have its memory expanded. You also forget the importance of the custom sound and graphics chips in the C64. Comparing the raw specs of the two units doesn't tell the whole story.
 
Anonymous Coward said:
A PC in 1981 didn't have 640k (due to BIOS limitations could only be expanded to 544kb).
Click to expand...

That is not correct.
You can place 640k of memory in a 1981 PC, and you can physically use it all. But due to a bug, early BIOS won't be able to detect it properly.
A BIOS update will fix that, but I believe our demo would run fine even without it.

You also forget the importance of the custom sound and graphics chips in the C64. Comparing the raw specs of the two units doesn't tell the whole story.
Click to expand...

Wait, you're actually trying to lecture me on my own demo?
The intro part of the demo already deals with most of that, as do some of the text screens introducing various effects.
 
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