Re: It's 286 time!
Posted on 2015-09-07, 07:32
286? VGA? Adlib? Sounds like a great system for 1991 donut 😀
Re: Am386DX-40 with L2 256Kb 15ns cache
Posted on 2015-09-07, 07:20
Don't forget the WD90C31 vgas, these are really great too - they score the same (or more!) as the ET4000 cards. Plus they have a program that switches MDA/CGA/etc modes that are reboot-resistant and actually work better after a reboot AFAIR in order to have better compatibility or something... Some …
Re: Help identify
Posted on 2015-09-06, 21:45
Oh dear, I think a friend of mine once had that board... Both PCI and VLB on a single board? That's asking for trouble :) We found that the VLB slots could only be used if you didn't have any ISA cards. It seemed that all ISA slots were clocked at VLB speed as soon as you used a VLB card. It caused …
Re: Acer 500+ XT system
Posted on 2015-09-06, 21:38
It won't be a problem if I skip the C64 comparison part, would it be? (and moire ofcourse) Well, hopefully you can use the new moire part, and it doesn't get stuck (or you use the old one and press esc yourself to exit it), so we can see (and hear) the whole thing. C64 part and calibration can be …
Re: Acer 500+ XT system
Posted on 2015-09-06, 21:28
Interesting. Do you think you could do a video recording of it? I wonder if the V20 actually makes a difference at all. It's mainly faster at instructions like mul and div, but we don't really use those in the inner loop, so perhaps the CPU is 'cycle exact enough' to make the demo work pretty much …
Re: Am386DX-40 with L2 256Kb 15ns cache
Posted on 2015-09-06, 19:38
Just a technical question: the huge speed gap of the ET4000 is cause higher internal clock/memory speed or different architectur? it's interesting to see that no other pushed isa bus that far. It's a combination of fast memory and a really clever memory controller. The problem with video ram is …
Re: Am386DX-40 with L2 256Kb 15ns cache
Posted on 2015-09-06, 17:35
Thank! But compared to the S3 805 VLB card I tested on a 486, is it much slower? Did VLB vs ISA both 1 or 2MB cards differed that much? The ET4000 is the fastest ISA card ever made, and at least in 320x200 mode there is very little difference in performance with a decent VLB card (it's fast enough …
Re: Hidden Power in AMDs 486DX4 SV8B WB
Posted on 2015-09-06, 17:29
Yes, 5x86 and 'P75' are just marketing, in response to Intel's Pentium. Very similar to the PR rating that AMD put on their Athlon CPUs in the Pentium 4 era. The CPUs were actually just 486-derivatives (which is why they perform so poorly in a game like Quake, which expects a true Pentium with a …
Re: Am386DX-40 with L2 256Kb 15ns cache
Posted on 2015-09-06, 17:25
You want a Tseng Labs ET4000 ISA card. Both Trident and Oak are notoriously slow cards. Problem is, they are ubiquitous because they were so cheap. So they went into every no-name clone. Also stay away from Realtek. Not quite as common as Trident or Oak, but every bit as bad, possibly even worse.
Re: Acer 500+ XT system
Posted on 2015-09-06, 13:53
I think I've found the problem: The code uses the undocumented 'salc' instruction (Set AL on carry): http://www.rcollins.org/secrets/opcodes/SALC.html This instruction is probably not supported by the V20 CPU. The thing is that the loader API signals that the effect should end in the carry flag. If …
Re: Windows and portability
Posted on 2015-09-06, 11:22
Windows and portablility don't really go together, unfortunately. It's funny how the most widely used OS is the one that's the least-compatible with what other OSes consider to be "standards". Or... it's funny how these other OSes seem to ignore the biggest standards in the OS-world. Even John …
Re: Acer 500+ XT system
Posted on 2015-09-06, 10:32
Well, I find it somewhat intriguing, since I don't see a direct reason why the moire effect would fail to end. So I may look into it. The other stuff is a problem... you'd have to tweak the code for every individual clone out there, so that's not really an option.
Re: Acer 500+ XT system
Posted on 2015-09-05, 23:17
8088mph.003 is the offending file, I just renamed it. Good to hear that's the only troublesome part. Still I have no idea what the problem could be. You say it just keeps running indefinitely? That means somehow the part that ends it ('wipes' the screen from the outside to the center) is never …
Re: Acer 500+ XT system
Posted on 2015-09-05, 17:36
I'd have to see what happens if I run it on one of my faster 8088 systems. I don't have a V20. Some parts might look wrong because of timing issues. Some parts do their own music timing, they may run too fast, but nothing should actually crash or loop forever. The parts that I developed (sprites …
Re: Acer 500+ XT system
Posted on 2015-09-04, 11:52
CGA doesn't output the cleanest signal I've ever seen... but this is worse than what I have seen on my systems. It could be caused by your power supply (there is little or no power conditioning on the card itself, and old power supplies aren't as clean as modern switching ones).
Re: Acer 500+ XT system
Posted on 2015-09-04, 10:31
I'd have to see what happens if I run it on one of my faster 8088 systems. I don't have a V20. Some parts might look wrong because of timing issues. Some parts do their own music timing, they may run too fast, but nothing should actually crash or loop forever. The parts that I developed (sprites and …
Re: My Future Super Turbo XT build
Posted on 2015-09-04, 10:06
mostly "premium-manufactures" like diamond have better image-quality then no-name stuff with the same chipset. That mostly has to do with the design and choice of components (lower tolerance) of the low-pass output filter after the RAMDAC. If you build the card yourself, you can choose good quality …
Re: Acer 500+ XT system
Posted on 2015-09-04, 09:01
^ you know what? now it's the time to test it , when things are not clones :blush: gonna write me that image and report back :D Yea, clone CGA cards also interfere with the timing of the rest of the system. When I used an ATi Small Wonder CGA clone in my real IBM 5160, the demo didn't work 100% …
Re: Acer 500+ XT system
Posted on 2015-09-04, 08:52
Wow, untouched by human hands! Very nice. It has the Motorola CRTC which I understand is better from a compatibility point of view. I don't think any PC software ever programmed the CRTC in a way that compatibility issues surface, aside from the party version of 8088 MPH. So it should be a non- …
Re: Acer 500+ XT system
Posted on 2015-09-04, 08:50
So, does 8088 MPH work? 😀
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