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

1ST1 said:
The M24 might be too fast as it has 8086 at 8 Mhz, but let's see what happens...
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End music will be too fast, but as a fellow M24 owner, we are used to that by now, eh? :)

If the demo runs to that point, you will see a nice surprise with the rotozoomer part (it performs better the faster a system you give it).
 
I suppose I could attempt to downclock the PCT. There is one 16Mhz crystal on it that I assume runs the system clock. Don't know if swapping in a 9.54Mhz part will work though. :p
Its still a v30 though, so timing will still be off even at 4.77Mhz.
 
reenigne said:
Hornet, CRTC and DESiRE are pleased to announce a final version of 8088 MPH
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Very cool! This one finally works on my full-length clone board (didn't try the shorter ones yet). Another notable improvement is that this EXE works with the not-so-compatible TSoft NFS client (with the party version DOS complained that it "Cannot execute", so the EXE had to be copied to floppy).

Still does "Internal stack overflow" on HP 200LX 80186 PDA :)
 
Tried the final version in my 5160 with a Paradise Modular Graphics Card CGA clone


Click to enlarge


The first screen seems to show NEW model, but I observe some green instead of blue in the text between scenes. All the hi-color scenes are shown in black and white, no matter what calibration settings are chosen.

Here is a video:
 
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nestor said:
All the hi-color scenes are shown in black and white, no matter what calibration settings are chosen.
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You need a composite monitor (or TV set, video capture device, etc. with composite input) in order for the high-color scenes to show up in color.
 
vwestlife said:
You need a composite monitor (or TV set, video capture device, etc. with composite input) in order for the high-color scenes to show up in color.
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I have a Commodore PC20-III with a Paradise PVC4 on board, and it does exactly the same thing: colorburst can not be enabled in 80-column mode. They probably did this as a safeguard, because enabling colorburst makes 80-column text unreadable. 80-column mode is monochrome on real IBM CGA as well, because colorburst is disabled. You can just enable it manually in code on a real IBM CGA.

As you can see, the other colours are somewhat off as well (you get a brown building behind the DeLorean, while it should be green). It all looks exactly the same on my PC20-III. It's just how the Paradise card was designed. Not 100% the same as CGA.
The colours during the polygon part are even more off, and look more like what you'd expect from a PCjr or Tandy.

Interestingly enough, the Kefrens bars show up correctly on this machine, which they don't on my PC20-III.

My ATi Small Wonder is similar... colours are off. However, it DOES enable colorburst. It just doesn't look correct :)
 
So I tryed the final version on Olivetti ETV 260 and ETV 2700...

The setup screen already is displayed wrong on ETV 260, in 40 characters mode and quite unreadable. I think you use a video mode which is not supported by ETV 260, ETV 500 and Olivetti M19 PC (use all the same mainboard). When runnijng however the demo many screens still shows totally uncorrect pictures. The only little improvenemt is that I can see the final screen with the greetings, but partially unreadable and in 40 characters mode, and it does not scroll down. The digital sound is loud but it is only noise, no music.

With ETV 2700 (based on NEC V40 CPU and monochrome FBAS connected CRT) the monitor stays totally black at all. No chance to watch it there as well.
 
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I *FINALLY* got a chance to try this on my Columbia Data Products MPC 1600.

The original version runs all the way through showing all of the scenes and, with the hue adjusted a bit, looks OK-ish, except for the 256/1K color modes, which look off.

The "Final" version also runs all the way through, but the colors look totally wrong, regardless if I select "new" or "old" mode. (The splash screen looks like it says "DED" :) ). Depending on the parameters I select, some scenes will appear in monochrome. Another odd thing, it says my CPU speed is off by 2%. Perhaps this machine isn't exactly 4.77mhz. I'll have to take a closer look and see what other speed diags think.
 
SomeGuy said:
The "Final" version also runs all the way through, but the colors look totally wrong, regardless if I select "new" or "old" mode.
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Well, most graphics didn't really change in terms of colours. If you select 'old' mode, most parts should look pretty much the same as in the party version.
The main differences are the rotozoomer (was green/brownish, now blue/orangeish) and the end-scroller.

SomeGuy said:
Depending on the parameters I select, some scenes will appear in monochrome.
Click to expand...

Yes, that's why the calibration screen is there :)
If you select the same settings as the ones hardcoded in the party-version, it should look the same (it only affects the high-colour parts though).
I believe the settings for the party version were:
hsync width: 0 (this one I'm sure of, that is the value that caused problems on clone 6845 chips)
phase: 0
border color: 7
 
Ok, I discovered that at different times my card randomly initializes differently. After watching a few more runs, I noticed that the colors even occasionally randomly changed during the program at the beginning of various scenes.

Attached are two different splash photos of two different runs of the program, with the same settings on the monitor. Also a photo of the best I could get the many-color image to look so far.

8088 Run One.jpg8088 Run Two.jpg8088 Colors.jpg

Thats what I get for not using true blue, genuine IBM, right? :p
 
SomeGuy said:
Thats what I get for not using true blue, genuine IBM, right? :p
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Pretty much :)
Our code makes a lot of assumptions about the hardware, such as the exact number of cycles that instructions take, and the output of the composite port.

As you know, we already had to adjust the graphics to cater for the 'new style' IBM CGA cards in our final version.
For every clone out there that has slightly different composite output, we'd have to redo the graphics again.
Likewise, code that depends on exact CPU/chipset timings would have to be re-done for every clone that is slightly different.

So, that simply doesn't work. We decided to approach the IBM PC the same way one would approach a C64 or an Amiga: all machines are EXACTLY the same, so if your code works on one machine, it works on all of them. Which is true for all IBM 5150/5155/5160s (now that we handle different 6845 chips and different CGA composite output circuits), but not all clones are faithful copies of these machines.
 
When you think about it like that, it's actually kind of mind boggling that PC clones were ever able to take off. There were a few business applications and games that seemed to be only 100% happy on IBM hardware. And vendors often had to take extra effort to "support" specific clones. Things could have been much more difficult for clone owners.
 
Well, I think it was partly due to IBM themselves, launching systems such as the AT and the PCjr, which were not 100% compatible either (even though the PCjr shared the 4.77 MHz 8088, it did not execute code at the same speed as PC/XT systems, and the video circuit was only partially compatible with CGA), which probably led to most developers writing somewhat more 'defensive' code in terms of hardware requirements. Variations in speed and other specs became the hallmark of the PC platform.

I guess the big success of clones was after 1984, when IBM themselves already 'corrupted' the PC/MS-DOS platform with incompatible systems.

Other system were different anyway. It was much harder to clone a system like the C64, because of all the custom chips.
 
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