Still working on GTIA V-Gate?

[+mytek]

1 hour ago, Beeblebrox said:

I think more clarification of a particular setup and images of the board and upgrades in situ is needed.  

Yeah that's what I was thinking as well.

 

It could be any number of things based upon the info we've gotten thus far. Some things to keep in mind with UGV: this upgrade is meant to completely replace the original Atari composite and S-Video output, and is especially true if you want the VGATE over scan disable feature to be active, since that screws up the original video output. So it's best to do the same as what many UAV users do, and cut the ferrites coming from the original video feeding the DIN-5 jack, and replace those signals with the UGV equivalents. For those who only require S-Video via a Mini-DIN-4 Jack, there is a solder-less interface board available that will break that out.

[wildstar87]

It is the UGV that is doesn't have color.  DVI is working fine through Sophia.  If I remove Sophia and put the GTIA back into UGV, color works fine.  I have wired UGV directly to the DIN 5 jack.  I'll take pictures when I get back home, but not sure that will help in this instance.  I have multiple machines with this configuration installed, all of them are doing the same thing with UGV.  Obviously something about the Sophia output is different, but it is working in UAV setups properly.  I did have the colored bars due to the W2 jumper before, so removed that.

Edited November 6, 2023 by wildstar87

[wildstar87]

5 hours ago, Beeblebrox said:

I may be missing something but are you plugging Sophia2 into the UGV, which in turn is just sitting in the GIA socket, and using it's DVI, but getting black and white?

 

Or are you just using Sophia 2 for the GTIA replacement, but ugv on Din3 as the output? Is UGV wired to the chroma signal to give the cable chroma?

 

CVBS (composite), Luma and Chroma should be wired to their respective signal points on the pcb. So on the XE its L7, L9 and L31 respectively and 3 x grounds. Then 4050 is removed.

 

Also perhaps you need to tweak the settings in the Sophiaconfig software if you are using DVI? Maybe one setting is stopping a colour signal?

Sophia2 is plugged into UGV piggyback, which is plugged into GTIA socket.  Wires have been directly run from UGV to DIN 5, not going through 4050.  Replacing Sophia with GTIA chip, color works fine.  I'll try playing with the Sophia settings to see if that's doing something to the color through CVBS/S-video.  I'll also check the CVBS line, I've only been looking that the S-video.  Sophia is outputting DVI through it's ribbon cable/DVI connector.

[Beeblebrox]

Thanks for the info. Do all the 40 pins on the sophia2 pcb check out? Are they all making contact with the UGV socket?

 

Images will be great. 

[+mytek]

6 hours ago, wildstar87 said:

It is the UGV that is doesn't have color.  DVI is working fine through Sophia.  If I remove Sophia and put the GTIA back into UGV, color works fine.  I have wired UGV directly to the DIN 5 jack.  I'll take pictures when I get back home, but not sure that will help in this instance.  I have multiple machines with this configuration installed, all of them are doing the same thing with UGV.  Obviously something about the Sophia output is different, but it is working in UAV setups properly.  I did have the colored bars due to the W2 jumper before, so removed that.

I agree with you that Sophia's GTIA aspect is likely where the problem originates. This is unfortunately what happens sometimes when FPGA replacements are created for the original Atari VSLI chips. However it's not really the fault of the Sophia, it's just the fact that I got away with something on the original GTIA that I can't on the Sophia's replicate, that being that I didn't buffer my color pickup from the color output pin. Whereas the UAV picks up color from the original Atari color buffer circuit, thus the reason it still works with the Sophia.

 

It might be possible to add a single transistor emitter-follower buffer - something I'll need to test when I find the time. This would be the preferable way to do it, since it would still get all of it's signals from the GTIA piggyback. However for existing UGV boards another possibility might be to remove the color capacitor on the UGV and then run a wire from one of its pads out to the Atari buffered color circuit - yet something else I'll need to test (this might end up being the best option on a revised UGV as well, due to space constraints).

[wildstar87]

 Here are the pictures, I removed the DVI cable in some, to get an unobstructed view.  Haven't had a chance to check the CVBS, just snapped these really quickly last night.

Edited November 7, 2023 by wildstar87

[Beeblebrox]

I see you have no ground wires connected to UGV for headers 2 and 6, but you have ground for header 4? Have you tried it with those 2 x headers grounded as well? 

 

 

In your wiring cvbs is yellow, chroma purple, and green is luma, directly wired to the Din5 pins so that should be good. All continuity checks out for those? 

 

Is the sophia2 pcb underside shorting against the UGV perchance? 

 

Have you tried the setup with the 4050 removed? 

 

 

 

 

 

Edited November 8, 2023 by Beeblebrox

[wildstar87]

16 hours ago, Beeblebrox said:

I see you have no ground wires connected to UGV for headers 2 and 6, but you have ground for header 4? Have you tried it with those 2 x headers grounded as well? 

 

In your wiring cvbs is yellow, chroma purple, and green is luma, directly wired to the Din5 pins so that should be good. All continuity checks out for those? 

 

Is the sophia2 pcb underside shorting against the UGV perchance? 

 

Have you tried the setup with the 4050 removed? 

 

 

 

 

 

Yup, continuity checks out, and again works fine with normal GTIA.  All the grounds are already connected in the J1 header, seemed to me that running individual grounds was kind of redundant, as they all connect to the same spot anyway in the Din5.  I could see it being convenient if you had separate RCA jacks, or separate S-video connector, but I'm not doing that.  Mytek can correct me if I'm wrong, but DMM resistance/continuity checks, those are all connected together, should be electrically the same.

 

I'll check and see if anything is touching on the backside, though I know Sophia doesn't have any components or open traces on the back of the dip section, and nothing on UGV in the dip pocket is high enough to touch.  The one larger resistor that you see in the upper right hand corner, is because I literally could not find a smaller one in stock, for that value.

 

Haven't tried without the 4050, it's easy enough to pull out of the socket, but since nothing is actually going through it, not sure what effect it would have.  The NTSC 600XL, literally does not have those connections, since it doesn't have the Din5 monitor jack by default, normally the Channel 2-3 switch is in this location.  This was a previously stock 600XL, so I didn't even bother putting the monitor jack circuitry and ran UGV directly to Din5.

 

@mytek If there is something that you want me to try out, I might have components handy.  When you refer to the color buffer circuit, are you talking about the 4050, or something else?  The UAV in my other machine has the UAV plugged into 4050 socket, with 4050 removed.  Given that I'm pulling the Color signal from top of R45 based in the install instructions, that seems to pull directly from Color pin on GTIA?  Is the UAV then doing some buffering itself, because now looking at 800XL schematics, the Color signal is being pulled before the three 2N3904 circuit.

[+mytek]

1 hour ago, wildstar87 said:

@mytek If there is something that you want me to try out, I might have components handy.

I might have some time this weekend to test a few things. Let me get back to you

 

1 hour ago, wildstar87 said:

When you refer to the color buffer circuit, are you talking about the 4050, or something else?  The UAV in my other machine has the UAV plugged into 4050 socket, with 4050 removed.  Given that I'm pulling the Color signal from top of R45 based in the install instructions, that seems to pull directly from Color pin on GTIA?  Is the UAV then doing some buffering itself, because now looking at 800XL schematics, the Color signal is being pulled before the three 2N3904 circuit.

No the 4050 does not buffer the color in any of the Atari 8-bit machines. it only buffers Luma and Csync coming from the GTIA.

 

Not sure what UAV does for the color, but it does sound like it might have onboard buffering of some kind for that signal.

[+mytek]

1 hour ago, wildstar87 said:

Yup, continuity checks out, and again works fine with normal GTIA.  All the grounds are already connected in the J1 header, seemed to me that running individual grounds was kind of redundant, as they all connect to the same spot anyway in the Din5.  I could see it being convenient if you had separate RCA jacks, or separate S-video connector, but I'm not doing that.  Mytek can correct me if I'm wrong, but DMM resistance/continuity checks, those are all connected together, should be electrically the same.

Opps missed this comment. Yep the extra grounds are mainly provided if individual jacks are being used, and it also adds a bit of shielding between signal wires when connected to the S-Video Mini-DIN4 interface board. However in some cases I've seen where using the additional ground wires can help keep the video noise-free by tying into existing ground points on the motherboard. here's an example of using the additional ground wires on a 65XE...

 

 

Full installation post...

 

[mimo]

Just want to say a big thanks to @mytek for making this available for people to produce.

I fitted one for a friend in his 800xl last night.

Despite the dim light and my rubbish eyesight the install is pretty simple and my friend was blown away with the improvement on his 800xl.

[Beeblebrox]

39 minutes ago, mimo said:

Just want to say a big thanks to @mytek for making this available for people to produce.

I fitted one for a friend in his 800xl last night.

Despite the dim light and my rubbish eyesight the install is pretty simple and my friend was blown away with the improvement on his 800xl.

I second that. Fantastic little board. Great image output and easier than a lot to install, (especially if your machine is already socketed). Makes a massive difference to XE machines in particular when compared to stock output. I buy them in the UK preassembled, off a very reputable seller on Ebay for a great price. I've installed them in XE A8s mainly, and a good few 800XLs.

 

For the most part for the likes of the PAL 600XL, I've not needed to add any video upgrade as the stock output of a 600XL on video, once chroma is installed and c109 cap removed, is pretty amazing. 

 

Edit: first time install in my 130xe earlier this year. BTW I always remove the 4050 chip when installing ugv in my a8s. Got a lil pile of em now.

 

Edited November 24, 2023 by Beeblebrox

[snicklin]

I really should wear my glasses when using my iPad, I initially read the title of this and thought someone was working on a version of GTA V. As crazy as that is.

[Beeblebrox]

6 hours ago, snicklin said:

I really should wear my glasses when using my iPad, I initially read the title of this and thought someone was working on a version of GTA V. As crazy as that is.

Heh Heh. Whatever next(?)... Doom on the Atari 8 bit....

[Overange]

The UGV is a great piece of work and a great credit to @mytek Hoping that Mytek does not mind 😇, I have taken the time and using the original design, recreated it in a Surface Mount option.

• Apx 3.5mm narrower to allow better clearance to a stacked ANTIC on the XE models, mainly the XEGS.
• SW1 replaced with 1.27mm jumper headers.
• Tried to keep component layout the same as the original version and tried not to deviate to much from that version, the only main changes are, U2 is now fully SM only and rotated 90 Degrees, U1 Moved over and rotated, D1 and R14 moved nearer U2
• Screen Print now shows Connection labels on the top side.

 

 

Tested has been done and the V Gate still works great  

 

However going back over this post, I have noticed some other improvements that could be made to this SM version.

 

600XL - Clearance from U24, cut out could be made, will need the video header moving to the right slightly.

Sophia Clearance, may need to rethink as to provide clearance from the Video and SW1 Headers. if some one can send me dimensions of the Sophia that would be great.

 

 

[+mytek]

12 minutes ago, Overange said:

The UGV is a great piece of work and a great credit to @mytek Hoping that Mytek does not mind 😇, I have taken the time and using the original design, recreated it in a Surface Mount option.

I don't mind at all. In fact that's the whole purpose of releasing the designs into the public - to give others ideas that they can build upon.

 

You definitely made it even smaller, while still having a very similar layout. Nice 👍

 

15 minutes ago, Overange said:

Tested has been done and the V Gate still works great  

Good to hear. Always nice when something works out as planned.

 

15 minutes ago, Overange said:

 

However going back over this post, I have noticed some other improvements that could be made to this SM version.

 

600XL - Clearance from U24, cut out could be made, will need the video header moving to the right slightly.

Sophia Clearance, may need to rethink as to provide clearance from the Video and SW1 Headers. if some one can send me dimensions of the Sophia that would be great.

When you get this into a form that you are happy with, are you going to release the gerbers? I hope so, and I would also like to add it and some of your pics to my UGV page.

[Overange]

41 minutes ago, mytek said:

I don't mind at all. In fact that's the whole purpose of releasing the designs into the public - to give others ideas that they can build upon.

 

You definitely made it even smaller, while still having a very similar layout. Nice 👍

 

Good to hear. Always nice when something works out as planned.

 

When you get this into a form that you are happy with, are you going to release the gerbers? I hope so, and I would also like to add it and some of your pics to my UGV page.

@mytekThanks  your work is defiantly a big inspiration to the community.

 

Technically it could be made smaller, but for those of us who can SM solder by hand, you do not want it to small.

 

Yes, as soon as the finished design is done, I will issue you the Gerber's, along with some nice looking photos.

 

Some other options I am thinking about??

 

• On completion and after is programmed, does it need to have the ICP header installed, This may help with 400/800 installations and if someone wants to switch the V-Gate, they can just fit there own switch cabling?

• With 600XL installations as well as chop the corner off, how about, chop the corner and change the Video Header from a 6 Pin header to a 5 Pin header, in the format of :-  CVBS - GND - C - GND - Y   Therefore if someone uses a ribbon style cable and it can still have a ground separating the cores?

 

Edited January 13 by Overange
Typo

[+mytek]

12 hours ago, Overange said:

@mytekThanks  your work is defiantly a big inspiration to the community.

 

Technically it could be made smaller, but for those of us who can SM solder by hand, you do not want it to small.

 

Yes, as soon as the finished design is done, I will issue you the Gerber's, along with some nice looking photos.

Thanks I have something else that I got quite sometime ago that i keep meaning to put on my site, the STLs from an AtariAge member for printing a case for the last MIDI board I made. So when I get those from you I'll try to get both things taken care of.

 

Of course I'll be sure to credit you guys on both creations

 

12 hours ago, Overange said:

Some other options I am thinking about??

• On completion and after is programmed, does it need to have the ICP header installed, This may help with 400/800 installations and if someone wants to switch the V-Gate, they can just fit there own switch cabling?

After flashing the chip the ICSP header is no longer needed, except for one thing, and only if someone wishes to disable the V-Gate function. The PIC12F1572 PDAT pin which is normally available as pin-5 on the ICSP header when taken to GND will do that. Probably be nice to still have that be there in some fashion perhaps as just a solder pad to connect a wire to.

 

12 hours ago, Overange said:

• With 600XL installations as well as chop the corner off, how about, chop the corner and change the Video Header from a 6 Pin header to a 5 Pin header, in the format of :-  CVBS - GND - C - GND - Y   Therefore if someone uses a ribbon style cable and it can still have a ground separating the cores?

 

Well that works for me, and that should still work for the Mini-DIN4 interface board as well if someone wishes to use that too.

[Overange]

10 hours ago, mytek said:

After flashing the chip the ICSP header is no longer needed, except for one thing, and only if someone wishes to disable the V-Gate function. The PIC12F1572 PDAT pin which is normally available as pin-5 on the ICSP header when taken to GND will do that. Probably be nice to still have that be there in some fashion perhaps as just a solder pad to connect a wire to.

 

Well that works for me, and that should still work for the Mini-DIN4 interface board as well if someone wishes to use that too.

Update:-

 

 

ISCP Has been moved up with silk screen to show V Gate link from the top.

Video Out connector is now 5 pin, in the format as mentioned before.

And some nice curved edges just to finish off the look  

Notch made in top left to provide clearance from U24 on the 600XL, photos below show how close it is.

and some slight track moves.

 

 

I will keep it as V1.3 on the finished design, to keep it in line with the originals Schematic version.

 

[+mytek]

9 hours ago, Overange said:

 

 

That looks very sexy

[Overange]

On 1/15/2024 at 2:17 AM, mytek said:

That looks very sexy

Sure is  

 

Here it is in the flesh 😆

 

You can see the size difference from the original TH design

 

I accidently snapped the Front part of the IC socket...

Here it is in an 800XL, I have to go and get my 600XL from storage to check the clearance from U24, but TBH it should be well clear.

 

All testing has been done and there does not appear to be any visible difference in performance from the original.

 

To really tighten up the tolerances, I am considering making it with 1% Resistors as the price difference is pennys.

 

 

 

[pseudografx]

Can the UGV be used in conjunction with UAV? While I'd like to have V-Gate, I also like UAV's fix to the GTIA timing.

[Overange]

UGV SM edition fitted in a 600XL - plenty of clearance from U24.

 

 

[+mytek]

3 hours ago, Overange said:

Wow that's a precision fit if I ever saw one

 

Looking very nice.

 

On 2/3/2024 at 1:15 PM, pseudografx said:

Can the UGV be used in conjunction with UAV?

I think it can work, although for UAV operation it'll most certainly require VGATE to be OFF since it can cause downstream issues with the original video circuitry, and the UAV ties into that. However no guarantees since I had absolutely no need to do something like this myself and thus never tested the idea of doing so.

 

On 2/3/2024 at 1:15 PM, pseudografx said:

While I'd like to have V-Gate, I also like UAV's fix to the GTIA timing.

I guess you are referring to the artifact adjustment on the UAV ?

 

Being primarily an S-Video guy, I never saw any need for that in the UGV design, even though it does produce very good quality composite in addition to the S-Video. I guess people want their artifacts to be correct

[pseudografx]

18 minutes ago, mytek said:

Wow that's a precision fit if I ever saw one

 

Looking very nice.

 

I think it can work, although for UAV operation it'll most certainly require VGATE to be OFF since it can cause downstream issues with the original video circuitry, and the UAV ties into that. However no guarantees since I had absolutely no need to do something like this myself and thus never tested the idea of doing so.

 

I guess you are referring to the artifact adjustment on the UAV ?

 

Being primarily an S-Video guy, I never saw any need for that in the UGV design, even though it does produce very good quality composite in addition to the S-Video. I guess people want their artifacts to be correct

I'm referring to this GTIA9-related issue, with dark lines in between certain luminances.

Left one is stock 130XE, right one is my UAV-modified 800XE. Both connected using S-Video.