3dfx Archive - Rampage dongle

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Rampage dongle 19.12.11 at 11:42:59 I'm considering doing some benchmarking with the Rampage board, anyone care to assist me with fabricating a dongle or even a stand alone device that will flip the video signal? Gary
Back to top	Rampage is alive! IP Logged

goriath

God Member

Offline

Ruggedized Retro Gamer

Posts: 599
Italy/Slovenija
Gender: male

Re: Rampage dongle
Reply #1 - 19.12.11 at 15:55:15

gdonovan wrote on 19.12.11 at 11:42:59:

....anyone care to assist me with fabricating a dongle or even a stand alone device that will flip the video signal?

So, that is what the dongle really does; it flips the image horizontally on the screen, left to right, right to left, right?

If not, what exactly do you mean for flip the video signal?

Back to top

OLD SCHOOL: Because it was done right the first time

IP Logged

NitroX infinity YaBB Moderator Offline Posts: 1936 The Netherlands Gender:	Re: Rampage dongle Reply #2 - 19.12.11 at 16:23:20 From Gary's own trivia section on his site; Quote: 3) Interesting bug in Rampage chip- The DAC was flipped, reversing the color channels.
Back to top	My Blog IP Logged

exxe God Member Offline ^^ Posts: 1316 germany	Re: Rampage dongle Reply #3 - 19.12.11 at 17:08:58 take a v1/v2 loop cable and flip the 3 colors lanes
Back to top	IP Logged

goriath

God Member

Offline

Ruggedized Retro Gamer

Posts: 599
Italy/Slovenija
Gender: male

Re: Rampage dongle
Reply #4 - 19.12.11 at 17:36:30

exxe wrote on 19.12.11 at 17:08:58:

take a v1/v2 loop cable and flip the 3 colors lanes

He can try. But I think that all those resistiors and sot23 placed on the PCB's dongle are there for a reason. Probably swap color channels is not enough; maybe change signal impedance is also needed.

A screenshot without the dongle could be a start to know how the colors are swapped, BGR GBR ....

Back to top

« Last Edit: 19.12.11 at 17:39:44 by goriath »

OLD SCHOOL: Because it was done right the first time

IP Logged

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Re: Rampage dongle Reply #5 - 19.12.11 at 21:56:48 exxe wrote on 19.12.11 at 17:08:58: take a v1/v2 loop cable and flip the 3 colors lanes Interesting idea, and nothing to lose by trying. Simple thing to do would be to try cable with a ATI or NV board first and see if it matches Rampages output. In DOS the Rampage output looks white and black instead of black and white.
Back to top	Rampage is alive! IP Logged

trevormacro God Member Offline Voodoo5k6 Gold SE, Legend & Mystical Edition Posts: 622 Gender:	Re: Rampage dongle Reply #6 - 19.12.11 at 23:11:03 Rampage Lite Dongle :
Back to top	« Last Edit: 19.12.11 at 23:11:43 by trevormacro » IP Logged

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Re: Rampage dongle Reply #7 - 20.12.11 at 01:28:54 trevormacro wrote on 19.12.11 at 23:11:03: Rampage Lite Dongle : Yes, everyone has seen the that one. The extra circuits might be for cleaning up image quality, will have to research further.
Back to top	Rampage is alive! IP Logged

trevormacro God Member Offline Voodoo5k6 Gold SE, Legend & Mystical Edition Posts: 622 Gender:	Re: Rampage dongle Reply #8 - 20.12.11 at 01:37:43 @gdonovan : Can you take pictures in Win98SE desktop please?
Back to top	« Last Edit: 20.12.11 at 01:48:40 by trevormacro » IP Logged

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Re: Rampage dongle Reply #9 - 20.12.11 at 12:08:40 trevormacro wrote on 20.12.11 at 01:37:43: @gdonovan : Can you take pictures in Win98SE desktop please? I will in a day or two when I get the test platform up and running.
Back to top	Rampage is alive! IP Logged

trevormacro

God Member

Offline

Voodoo5k6 Gold SE, Legend
& Mystical Edition

Posts: 622
Gender: male

Re: Rampage dongle
Reply #10 - 20.12.11 at 18:17:55

@gdonovan :

To make that Dongle you need to reverse engineer it and build a schematic--which you can't do easily from only looking at a picture of it.

I read on another forum " This is an accessory that works as a filter to correct I/O video signal since there are some defects in the silicon layer" , so the dongle fixes more than just RGB color pins or whatever problems you guys thought it corrected. Furthermore, I found: " Monitor link requires an interface circuit named Dongle for level and impedance adjustment." So the transistors and resistors seen on the dongle board are used for correcting voltage level output and/or matching impedance output to the monitor (monitors are typically terminated with 75ohm to ground with VGA).

If you can find a schematic for the dongle board, you can easily reproduce it. If you can't find a schematic you will need to find one of those dongle boards and reverse engineer the schematic by hand (maybe ask NightBird on 3dfxzone.it/enboard)-- and then the trick will be finding the right transistors as I doubt they used general purpose transistors. Then you can definitely build your own.

Back to top

IP Logged

Loeschzwerg

Senior Member

Offline

AAlchemy PSU maker :-)

Posts: 396
Germany -> Bavaria -> Augsburg
Gender: male

Re: Rampage dongle
Reply #11 - 20.12.11 at 22:19:40

trevormacro wrote on 20.12.11 at 18:17:55:

I read on another forum " This is an accessory that works as a filter to correct I/O video signal since there are some defects in the silicon layer" , so the dongle fixes more than just RGB color pins or whatever problems you guys thought it corrected. Furthermore, I found: " Monitor link requires an interface circuit named Dongle for level and impedance adjustment." So the transistors and resistors seen on the dongle board are used for correcting voltage level output and/or matching impedance output to the monitor (monitors are typically terminated with 75ohm to ground with VGA).

I don't think this dongle is made for filtering purpose, therefore the dongle is optically too simple. Also this statement with the "impedance adjustment" seems wrong to me! The card would not create a clear picture if there are such problems. The only thing we know is that the colors are inverted, nothing more.

Here a quote from Gary's Rampage FAQ:
Quote:

11/29/00 Rampage is running but there are some stupid bugs. The DAC output is reversed ... high is low and low is high which turns out to be rather sucky since displaying is difficult. Looking at a dongle to invert the inverted output. Flash ROM bug where part can't be written... Fixes for both are possible in metal layers.

I think Sirta got a few things wrong when he did his "review" of the card and its dongle.

In my opinion a simple inverter for the color lines would do the job. This is nothing special an can be done very quick.

Back to top

« Last Edit: 21.12.11 at 11:41:19 by Loeschzwerg »

IP Logged

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Re: Rampage dongle Reply #12 - 21.12.11 at 11:55:56 Looks like I might have a dongle in the works, if I have spare time tonight I'll dust off a suitable platform and do some screenshots.
Back to top	Rampage is alive! IP Logged

m14radu God Member Offline Take your chance ! Posts: 555 Timisoara, Romania Gender:	Re: Rampage dongle Reply #13 - 21.12.11 at 21:50:55 Great news Gary !
Back to top	IP Logged

gdonovan YaBB Administrator Offline Infernal Collector Posts: 2361	Re: Rampage dongle Reply #14 - 22.12.11 at 01:48:04 m14radu wrote on 21.12.11 at 21:50:55: Great news Gary ! The dice are clicking, I feel it in my bones. Stuff is happening, woot!
Back to top	Rampage is alive! IP Logged

	Welcome, Guest. Please Login