new arcadeVGA & scart RGB cable problem? help please

[Midnight Tboy]

hey there,

I've just had a new arcadeVGA card from ultimarc, and a suitable (radeon without the audio cable) lead bought fresh from http://www.keene.co.uk (

[Midnight Tboy]

slight update - I managed to get the drivers from the cd installed by some epilepsy-inducing staring at the screen to work it out - still no joy with the flickering tho - on any computer....

I also noticed the arcadevga card has jumper pins, for ntsc and pal - default was at ntsc, so I switched them over - again nothing different   please don't tell me I've wasted a hundred quid for no reason

[Midnight Tboy]

another update - I tried using my newest pc, using an nforce2 motherboard, as on here I seemed to see a rumour about some problems with some via motherboards (which the old one was) - exactly the same problem.....I then reconnected my geforce4 card, and tried that svideo (with the composite yellow cable) straight to tv...and it worked fine - which didn't work in the arcadeVGA card).....when I changed to Pal on the jumper pins it surely would have worked if anything then but still nothing - do you think I need to get the card sent back?  I know Andy from Ultimarc frequents this site...I hope you read this too and have any ideas Andy

Cheers,
Tuck

[Midnight Tboy]

yet another update - slight progress.....

whilst the screen flickers like crazy, I managed to (miraculously) change the screen resolution using keyboard shortcuts as a mouse was impossible....it then changed the res to 800x600 32bit......the screen was visible then but it still scrolled and scrolled although at a fraction of the speed compared to the other modes, so I could actually see what I was doing....

on playing about, changing it to 640x480 or anything lower seemed to cause it all to go back to major fast scrolling.....dropping the 60hz refresh rate to 53 etc in "List All Modes" made the screen go mental and very unviewable.

With that, I tried running mamewah at 800x600 setting.....crisp colours etc but yet again the same scrolling - on running some mame games (admittedly I haven't setup that mame res utility thing yet), some were the same scrolling speed, other games (like outrun) went superfast scrolling again, and the same with likes of Daphne emulater....so theres definately an issue there somewhere...

I'm now thinking, is there a chance that the Keene have given me a wrong type scart lead?  I seem to keep reading bits on H and V sync being wired to component or joined together or something, which confuses me.....which should I have/which will I need?

[Midnight Tboy]

could this be related to the problem?

the cable I ordered from keane.....when they order it for you they send you their "disclaimer" a link to this site saying it is made to this exact spec

http://ryoandr.free.fr/english.html

now I've taken my scart end apart and had a look at it and there is a difference....if it makes any odds tho I don't know.

http://ryoandr.free.fr/pinout.png

on that picture.....it shows a 75ohm resistor crossing 2 of the pins......all the solders and the resistor are layed out correctly as per that diagram...apart from one thing....the brown wire shown in the picture is connecting to the right hand pin with the resistor....on my cable it is soldered to the left side of that resistor.

would that make the difference?  if that is what would fix it....I'll be really pi**ed off, and even tho its a quick few minutes to solder that wire to the correct spot, I'll prob send it back for replacement out of principle...after all

[Mr-Megalo]

the 75ohm resisitor betweens pns 8 & 16 is for widescreen mode

in my experience with the AVGA it is always best to do a full re-insatll from a freshly f-disked and formatted hard drive and full re-install with the AVGA in from the start

also, I would try to use 640x480 and increase to 800x600 later

[Midnight Tboy]

its not so much that the 75ohm resistor is on wrong - the wire is connected to the wrong side of it - should that matter?

like I said tho, even if I turned the pc on with no hd's attached, ie the bootup, bios etc  are all messed up and scrolling really fast too - it'd be nigh on impossible to do a full fdisk like that and the HD isn't an issue anyway if its doing it from bootup, as not driver related

[Mr-Megalo]

to be honest it sounds more like a sync problem to me

[Mr-Megalo]

just checked one of my scart leads that I had to tinker with for a supergun project for someone, the wire that you have on pin 16, mine is on pin 8 with the resistor going to pin 16

[Midnight Tboy]

hmmm so there's a chance that the shop messed up making the "custom made" scart lead, as mine is def on pin 16 with the resistor going between that and 8....either that or it makes no odds which side its on providing its there....can anybody clarify that any further?

also mind, it still doesn't really explain why I'm getting no output in the TV Out of the avga card....the same svid connector at the end of the avga, however the cable then converts to a yellow plug type for composite in....maybe it would work if I can get my hand on a full length svideo-to-svideo cable....but I'd rather solve the other problem first

[Midnight Tboy]

I also tried this on the second scart socket of the widescreen tv downstairs, and all I get on that is a pure white screen, in fact I was impressed with how white the screen was ....so I'm assuming that the 2nd scart socket does not support rgb at all

[Mr-Megalo]

silly question, but I take it you have tried both scart sockets on your Phillips TV ? one of them may be for composite only

*just as I pressed submit*
Warning - while you were typing a new reply has been posted. You may wish to review your post.

that answers that then

[Mr-Megalo]

drop a mail into keene and see what they say

[Midnight Tboy]

heya yeah I tried it in both on the phillips tv too aswell as the widescreen tv...the phillips tv did exactly same on both of them - ie just a black bar on top - worst case scenario is I'll just resell on the tv if it won't do rgb, but it was the widescreen tv that did the white screen on 2nd scart.....good idea though, I'll email keene shortly and see what they have to say about it....mind they prob won't get back for a couple of days with it being weekend

[Mr-Megalo]

phone em up Monday,

I personally am particularly interested in how this turns out, theres always someone wanting the VGA to Scart leads and I'd also be interested to know what the quality is like if they do work as they should

[Midnight Tboy]

email sent to them anyway

if needs be I may still call them.

I'm just hoping someone on here knows what may be causing the problem, and if that is indeed a probable cause to the problem of the scrolling, especially at the lower resolutions (which is no good for mame)

[Midnight Tboy]

I must also add - I haven't yet opened up the VGA D15 side yet to cross reference everything else is in its correct place....I'll do that tomorrow

[Midnight Tboy]

I had this reply on the mameworld.info forum...

---------
Change the wire to the other pin, reason is this, instead of directly feeding the brown wire to that pin you aree resisting it down and the side that is supposed to be resistor controled is bieng fed full "power". change it first before you send it back and if it works tell them that you would like a partial refund you might get lucky and get it. eather way you have the stuff there play with it and if it does not work send it back no loss to you.



--------


and my reply

-------



thanks - I will have to take it to my parents, I think they may have a solder iron there...trouble is I have never even attempted to solder for about 15yrs+ (ie school days) so reason I bought the cable in first place was so I could have everything up and running, then replace the 'confirmed working' bits with my own made bits (like a keyboard hack instead of the ipac etc)....I'm thinking though would this not invalidate my warrenty with Keene so they could refuse to take a return?  if needs be I'll have to call them on monday

cheers,
Tuck


----------

can anyone on here help still?

[Midnight Tboy]

hmmm well I had a go at resoldering the wire over to pin 8, the first time I plugged it in, exactly the same problem...flickering screen.

now my soldering skills certainly leave a lot to be desired and several big blobs removed and retried each time till it looked reasonably acceptable.

Seeing as it was doing exactly the same with the cable on both sides, I then tried to see if it still scrolled without attaching that cable to any and tucked out of the way.

This time the tv just gave a pure white screen like (with a teeny bit of flicker once in a while.

I then soldered back to pin 8 again (not 16 the original one), and its still giving me a white screen?

anyone know the reason for this?  blown resistor? just need to unsolder that side and start again? some other problem?

cheers,
Tuck

[Midnight Tboy]

something to add to my confusion of possible answers....

take these to websites for scart info

http://www.idiots.org.uk/vga_rgb_scart/index.html (which I shall now call TECH1)


and

http://www.mameworld.net/dosmame/advanced.php  (which I shall now call TECH2)

and the original one which this radeon cable is designed around (minus the wrong-way round wire)

http://ryoandr.free.fr/english.html



the main difference I can see, other than the lack of a resistor on one of them, is with vga-sides pins 13 and 15.

The other radeon cable page, and TECHA have only pin 13 connected.  TECHB has pin 15 connected too.

on TECHB's page, it says 15 Vertical Sync -> 20 Composite Video In on the scart. joining the same pin as the HSync one on the scart side.

Now that would make sense in theory?  hsync stable, screen rolling up and down, so vsync not connected?

but surely why would the other sites not have that connected, there must surely be some reason for it?

do you think this would fix the job?  the trouble is...the cable only has the necessary amount of wires in for the radeon job - ie 1 short - I could hardly thread in a cable through the inside of it :-/

[Midnight Tboy]

yet another addition

TECHB page also says after.....

-----
If you experience problems with sync-ing AFTER you run the TV-VGA driver, try connecting pin 20 (Composite Sync) to Pin 16 (Blanking Signal)
-----

hmmm now does that mean I should not need to even bother with the vsync on the vga pin side and do that, or do both or what gaaaaaaaahhhhh

btw...anyone even here?

[Midnight Tboy]

ok so I ran a single wire to pin15 running down the side of the cable- and no result....tv switched to AV1, but no picture...so I unplugged that cable and it ran fine again (well - with the jerkyness)


nowwwwwwwwwwwww.... I was pointed something out...vsync is apparently on pin14 not 15....so I checked again the TECHB link ( http://www.mameworld.net/dosmame/advanced.php )....where it says to connect is 15 Vsync...however further up the page it does indeed say 14...grrr what an annoying type for them to make

time to try it to 14

[Midnight Tboy]

whoooohooooooooo sorted it!!!!

I tried to attach a second wire running down the side of the cable to 14.

however, with my cruddy soldering skills it devoloped into a big blob and I disconnected 13 by mistake   on cleaning the solder up, I managed to get a 'weld' between pins 13 and 14 with the single cable that was already inside - heh heh cunning

so I didn't have to use that 2nd wire as its joined at the vga end

now picture comes on perfect

now to tinker with diff res modes till I break it again -

hope my tinkering is of more use to others,

Tuck

[Mr-Megalo]

nice - at least you've got it working now, be sure to post some pictures of your setup 

[AndyWarne]

I suppose I should have noticed this thread before but, if you had emailed me about this I could have helped.
There was a good site on this subject (MameScart) but it appears to have gone. I will try to contact the author and get the pages put up somewhere.
Andy W

[Midnight Tboy]

heh sorry andy I should've emailed you anyways...not to worry though I got it sorted in the end.

on another note, earlier I said that I had it working initially but with a jumping screen on the big widescreen and the smaller 14" tv, yet I only had a black screen on the 25" phillips.

well I decided to have another tinker about.  When I finally got it working again (after I temp broke the cable), I had the wire alongside the resistor back on on pin 16 ( where according to the guide it should've been on pin , and it worked fine, however it worked fine on either side for those 2 tv's.  The phillips 25" tv however, out of curiousity, I just earlier tried to resolder the wire back onto the pin 8, and it works fine on that telly this time, and still works on the other 2 tv's - so basically some telly's definately can auto detect or compensate for that error, but one thing to check for if someone is troubleshooting.  Now all I have to do is work out how to change the overscan on the TV.. I have the service code for the tv, but notta clue on what to change in its menus.

The company I bought the cable from, Keene, offered a full refund if I wanted, I could just put the cable back to its original state and return it,

[Silver]

Glad you managed to get it all working in the end.

Afraid I lost track slightly of the pin numbers through the thread, but I am I right in saying that they had just hooked up the Horizontal sync from the VGA card to the composite sync of the Scart connector and left it like that?

And your fix was to also solder the vertical sync onto the same composite sync connector?

[Midnight Tboy]

heya,

yeah thats pretty much correct.

I was told that this was the type of cable I should buy....and Keene were meant to make it up to this spec

http://ryoandr.free.fr/english.html

It was exactly the same as that cable, however where you see the resistor on the scart end, that brown wire was on the wrong side of the resistor which was the first main error causing problems.

The second problem, yep, was that, as to the diagram, the Vsync is not wired up at all, which is why I was scratching my head for ages trying to get the bugger to work.  So I basically soldered a join (or u could make a wire - prob better to be honest ) from pin 14 to pin 13 (both on the vga connector side) in order to have both of them connected to pin 20 on the scart.  Why on earth the cables made don't seem to have a vsync is beyond me.  do some tv's work fine without a vsync?  I wouldn't have thought so... :|

The only problem that having the wire on the wrong side of the resistor was causing the Philips tv not to be able to show the screen...the other 2 tv's were fine.

It was on this site, http://www.idiots.org.uk/vga_rgb_scart/index.html , where it talks about "Scart Control Signals", and this sentence "Some newer TVs seem to be able to detect if an RGB input is being applied to the SCART socket without this signal being set correctly, so you may not need it.
", that I thought the wiring may have had something to do with it even though that refers to powering it from the pc power supply, so I swapped it round again to the CORRECT wire on the scart side and it now works spot on.

When I get time, (hard with a 7month baby), I'm going to get a homemade cable made up, and try it without a resistor on there, to see if its even needed at all, as the various different guides, a lot dont even have one on there.  ok so its onliky 10p to add a resistor to the cable but no point if no need

[Silver]

Ok thanks for clarifying....

I'm surprised they did not hook up the vsync. Can't see it working well without it.

Creating a composite sync by just combining the vsync and hsync wires (as you have done) is not really meant to work although a lot of tv/monitors seem to cope. (worked for me to a while back).

FYI you are meant to convert the syncs - theres a homebrew circuit on how to make a "proper" composite sync from a VGA output here:

http://www.tkk.fi/Misc/Electronics/circuits/vga2rgbs.html

[Midnight Tboy]

heh crikey - there's so many diff types of scart cables that apparently 'could' work it's a nightmare.  Guess I was lucky then with the Tv..and I'll prob start crying my eyes out later when I work on the 2nd arcade cab and stumble across a different problem

[lettuce]

Should have gotten one of those cables from Ebay, a seller on there is selling them for

[Silver]

Yes its not made clear what exactly has been wired in the connector though. I'd be interested to know if theres any resistors in it etc..etc...

[lettuce]

Midnight Tboy, did keene.co.uk, mess up the cable then or did it just not work for what u wanted it for?, so u had to mod it yourself??

[Midnight Tboy]

hiya,

yes they did mess up the cable.... technically in one way, but really in 2 though you could argue they're not to blame

the thing they DEFINATELY messed up on was soldering the wire on the wrong side of the resistor - it caused it not to work on some tvs but still work on others.

The second thing, is there was no vsync wired up, ie one wire less in the cable.  This is what you could argue is their fault or not....I can't see any reason it should not be wired up but it isn't, but all my tv's definately needed it.  However, they tell you they're going to make it to the spec of the website http://ryoandr.free.fr/english.html (see where the wire should be on the side of the resistor in the pic), and technically (other than that wire error) it is, as those schematics have no vsync attached either.

basically without the vsync wire, the screen shaked up and down like crazy....with it it was fine...so one would assume that taking away the hsync would make it scroll left to right I would expect (not that I plan on trying )