Re: Pravetz-16ES 80186-8 IBM PC Compatible computer from Bulgaria
Posted on 2023-07-01, 19:04
One last picture
Re: Pravetz-16ES 80186-8 IBM PC Compatible computer from Bulgaria
Posted on 2023-07-01, 19:03
A few more pictures.
Pravetz-16ES 80186-8 IBM PC compatible computer from Bulgaria
Posted on 2023-07-01, 19:03
I am in the process of acquiring this computer from a seller in Bulgaria. I have only read about Pravetz computers, but what I found so interesting about this one is that is IBM PC compatible with a 80186-8 CPU. The computer is listed as in perfect working condition. I am very anxious to get it and …
Re: SPEGA EGA video card help
Posted on 2023-06-27, 19:30
I notice it's the classic Chips & Technology chipset. C&T were one of the first companies to clone the EGA. Top Left: 82C431 Graphics Controller Top Middle: 82C433 Attribute Controller Top Right: 82C432 Sequencer Middle: 82C434 CRTC And an EPROM on the bottom obviously Any idea what the other gate …
Re: SPEGA EGA video card help
Posted on 2023-06-27, 19:22
analog_programmer wrote on 2023-06-27, 19:11: I can not help you with documentation, but I see an EPROM with "open window"... better off put on some non-transparent sticker on it, if the BIOS is still fine. The pictures was from the seller...I already put electrical tape over the BIOS windows when …
Re: SPEGA EGA video card help
Posted on 2023-06-27, 19:19
It's likely that this card is just a EGA clone with no enhanced functionality. For example, I only see a 16.257MHz oscillator, but no other oscillators that would be required for higher resolutions. In the case of standard EGA clones, it is likely that the DIP switches for monitor selection work …
SPEGA EGA video card help
Posted on 2023-06-27, 00:58
I just picked up this EGA video card. I have been unable to find any documentation for it. It has SPEGA-00 Rev 1.2 silk screened along the bottom. I think it may be a Sigma Designs card. Any help would be appreciated, specifically the 4 dip switch settings for this card. Thanks!
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-23, 16:29
This is one of the most rewarding parts of vintage computing. Having a long forgotten technology brought back from obscurity and being given a 2nd chance. It doesn't get any better than that!
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-23, 02:36
I've been able to build the Abrash test code for the CEG, here is the executable L1.EXE and a link to a recorded video https://twitter.com/viti95/status/1672023500729507840?s=20 . I know the video quality is nowhere near good but proves it works!! It tested the L1 program on both my ET4000s one …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-14, 19:09
There was an SDK for the Edsun CEG RAMDAC. Analog Devices acquired Edsun Laboratories in 1991. I have been unable to locate it anywhere including using archive.org to search Analog Devices website as far back as 1997. Anyone know where a copy can be found?
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-14, 02:07
Here is PV a DOS picture viewer that supports the Edsun CEG and .CEG files. I have not been able to locate any .CEG files but I am attaching the program in case anyone is interested. The PV.DOC file is in German, so I ran it through Google Translate and I have included the translated PV-EN.DOC file …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-13, 22:29
I got the Edsun EL171 CEG RAMDACs today. I installed one and did some testing. Static images look fine, but when doing cycle cycling the picture has interference. I think the issue may be that the EL171 is running at 50MHz and the Samsung RAMDAC I took out runs at 80MHz. I have a ADV7146 coming and …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-13, 03:29
I got the Edsun EL171 CEG RAMDACs today. I installed one and did some testing. Static images look fine, but when doing cycle cycling the picture has interference. I think the issue may be that the EL171 is running at 50MHz and the Samsung RAMDAC I took out runs at 80MHz. I have a ADV7146 coming and …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-10, 22:22
I was also able to source a ADV7146 CEG RAMDAC from tvsat_electronic in Poland. It should be interesting to see if this is much different the Edsun CEG EL171 RAMDAC.
Re: Cardex ET4000 ISA video card jumper settings
Posted on 2023-06-10, 02:15
I finally found the jumper settings for this card: JP1 - IRQ2 Line Status 1-2 - IRQ2 Enable 2-3 - IRQ2 Disable JP2 - MCS16 Line Status (Jumper not present - Permanently soldered to 1-2) 1-2 - ET4000 VGA Chip generate 2-3 - External decoder JP3 - Turbo Mode 1-2 - Disable 2-3 - Enable
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-10, 01:58
ViTi95 wrote on 2023-06-09, 09:08: The ADV7148 datasheet show more information on how those CEG RAMDACs work. Even provides code examples: Thanks!
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-07, 02:11
At the very least it should act as a normal 8-bit color RAMDAC if it is truly a drop in replacement. To get the Anti Aliasing features, you need to include that logic in your graphics code. Too bad it is not automatic, but we are talking 1990 technology after all:) The ebay listings say they're …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-07, 01:21
Yep that's the one :) I bought some SiS chipset QFP chips from them and they were new with no solder on the legs and packaged properly. Your chips should be good too I suspect. Should be interesting to see if it works and if it makes an appreciable difference. Since you're working with the DIP …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-07, 00:02
Thanks for sharing this, I hope you can share some pictures if you spot any differences. Looks like they're drop-in replacements for DIP28 / PLCC44 RAMDACs from that era. If that Polish seller is who I think it is, they sell good parts. Actually new if it says it's new and the packaging is very …
Re: Edsun CEG (Continious Edge Graphics) RAM DAC
Posted on 2023-06-06, 19:05
I just wanted pass along the following link that has a PDF with a really good article in Analog Devices Number 3, Volume 24, 1990. Analog Devices RAM DAC used the Edsun CEG scheme in their implementation. Sounds like it would basically be the same thing as the one from Edsun Laboratories. You may be …
Page 5 of 28