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CGA connection to Taxan RGBvision 420

falter

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So, I've got my Taxan 420 here, and it seems to be alive - I turn it on and get a white screen. So I thought I'd rig up some wiring between it and my Mindset to see if I could make it work. According to the guide and back of monitor I set the switch to I. I then used jumper wires to individually connect between the round DIN connector and RGB - 7 wires in all, 2 N/C.. red to red, blue to blue, intensity to intensity etc. Triple checked.. but when I power on the screen stays mostly white with some red and blue lines here and there. Is the monitor hooped? Or did I miss something? I dimly remember something about the outer metal of a db9 being a shield of some sort..
 
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I'm thinking maybe I should try something else like composite with my Apple II and see if that works before digging in more with the cable. But I'm confused.. reading the manual, if I understand correctly, Mode II delivers composite.. but what pins is it using? They describe having a specific Taxan cable.
 
It shouldn't be rocket science to make it go; I would throw out the caution that it's easy to get confused when reading DIN connector pin layouts as to whether the diagram is showing you the point of view of the male or female end of the connector.

FWIW, if you are just trying to stuff the bare ends of wires in to the holes getting a clean connection might be easier said than done.
 
Is it possible to damage anything doing this? I checked the wires and powered up again this am and heard kind of a static crackle for a sec. I'm not sure if it's the normal static noise you often hear on CRTs. Nothing smoked and the computer seems fine. The monitor just gives white with waves when you turn it on now. I suspect you're right.. I think these little jumper wires maybe aren't making enough connection. I've ordered a cable but could only find one with what seemed like the right pinout in England.

I'm not sure if I understand this monitor properly.. I think it is entirely RGB based and switches mainly between analog and digital. What's confusing me is it mentions composite and in two modes has composite sync pins. It also has a mode that mentions Apple II, but I'm not sure if they mean Apple II w/RGB.

Wish they had just used the standard 9 pin dsub.
 
Is it possible to damage anything doing this?

I'd probably be more worried about damaging the computer you're trying to drive it with than the monitor, IE, it might not be super healthy if you started accidentally grounding driving signals, but mostly you should be okay as long as neither end has any extraneous/dangerous signals. (For instance, the first rev. of the Tandy 1000 for completely inexplicable reasons had +12v on one of the unused CGA pins; definitely risk of trouble if that inadvertently got hooked up...)

So when the manual says "composite" it appears to be referring to Composite Sync, and all that means is that both HSYNC and VSYNC are carried by a single mixed signal line instead of separate TTL signals like CGA. It's fairly common on non-PC computers, and some monitors actually support both without needing a switch, IE, if you feed a composite sync into either the Hsync or Vsync line they'll successfully figure it out.

Reading the manual the three settings seem to boil down to: MODE I = CGA compatible RGBI with separate sync, MODE II = TTL or *maybe* analog? (with nonstandard voltage swing) RBG-no-I with composite sync, and MODE III = Same as mode I but composite sync. I assume a Mindset wants mode I but I have no idea; if you have a more conventional PC with a CGA port lying around it might make more sense to try that first.

Re this:

It also has a mode that mentions Apple II, but I'm not sure if they mean Apple II w/RGB.

Taxan sold an RGB card for the Apple II called the "RGB-II", it looks like they're referring directly to that card.
 
Okay. I was a bit confused there - thanks. I have a Zenith ZVM-135, and it can do both RGB TTL and composite. Mindset is supposed to hook up to a CGA RGB monitor, so I would think Mode I applies as well. It does deviate slightly from standard CGA in that pin 7 (I think, one of the normally free pins) is used for keying. I didn't connect that one obviously. I mean, I got this monitor for $60 'untested', so who knows.. maybe the seller already knew it wasn't working. But I guess I'll have to reserve judgment until I get a proper cable. Sure looks nice on the Mindset though.
 

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It works! Getting a proper cable was all it took (surprise surprise). I found a 'Philips 8833' 8 pin DIN to 9 pin RGB from an ebay seller in England, and it works perfectly! I've finally broken my curse of having only one working RGB monitor! Double points because I paid $60 for the monitor, *and* it survived shipping!

Now I want to get my ZVM135 working with my Mindset PVGS - but there we have to go from 9 pin to 25 pin. Mindset gave instructions on how to make the cable, but I was kinda hoping it existed somewhere already.
 

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According to the Taxan guide there are 8 pins, yes - 1 of them is 'open', the other 7 are all used, everything from ground to RGB to sync and intensity. But I suppose it depends what you're connecting to.
 
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