C0pperdragon GTIAdigitizer (for Atari 8bit)

[Beeblebrox]

26 minutes ago, scorpio_ny said:

Also, C0pperdragon is based in Austria, not Australia

Heh Heh, my bad.

 

Yeah, I am not blaming the vendor and that was not my intention. Scaled up I see the benefits. 

 

I've just got very confused as I am used to standalone, internal and basically straightforward video upgrades. 

 

I think it's great this is another option for a great digital video output. 

 

I just think it's mounting up cost wise. 

 

Generally I run most of my a8s off S-video, (majority), VBXE rgb, (x2), Sophia 2, (x1), ugv, (x3), or SpectreAV, (2x). I wanted to try each new upgrade out when they became available. I don't have any a8s running off composite and it goes without saying rf doesnt get a look in. 

 

Thanks everyone for your help and input. As I say normally I work these things out. I think I rushed I to buying a lot of the kit for this one without fully understanding things. My bad. 

 

 

Edited December 2, 2023 by Beeblebrox
Adding extra info

[+mytek]

3 minutes ago, Beeblebrox said:

Thanks everyone for your help and input. As I say normally I work these things out. I think I rushed I to buying a lot of the kit for this one without fully understanding things. My bad.

Actually I almost did the same thing as you, but decided to put the brakes on and start asking more questions. Otherwise I know I would have ended up with the wrong Pi Hat for one

[Beeblebrox]

Yeah this multifaceted LumaCode system is not exactly easy to comprehend

 

I have to agree with Mytek.. I must admit it's all a little confusing. (And if someone like Mytek can find it confusing, that's saying something as he's not exactly new to all this.

 

 

[+mytek]

This is the main problem that caused my confusion. Notice that both products use the terminology of 'RGBtoHDMI' to describe what are very different boards, but both work as a 'Hat' for a Pi. The difference is that one's LumaCode specific, whereas the other is not. in some of the videos that have been posted demoing the LumaCode system they don't show much if any detail what the Pi side of things really looks like, and many times just use the term 'Pi with RGBtoHDMI Hat' to describe it. A lot of times no mention is made about a LumaCode specific version of that Hat.

 

 

 

Notice also that the LumaCode specific Hat has what appears to be an integral RCA cable, but wait they also sell this...

 

 

What's this cable for? Certainly it's not for the LumaCode specific Hat which already comes with an integrated RCA cable.

 

So the best I can figure is that it's meant to be used with maybe what I show below, that being a separate analog board meant to mate up with the first RGBtoHDMI Pi Hat I showed at the top of this post?

 

Yeah there's absolutely no reason for any confusion

 

 

EDIT: If you pay very good attention, you'll see that the top of post RGBtoHDMI adapter mentions that it converts Digital RGB to HDMI. Because LumaCode is actually an analog coded signal with different voltage levels representing different data bits, it requires an Analog input

[+mytek]

Based on what I've learned, I went back and edited a previous post that breaks down all that is needed to put this LumaCode system together. I linked the COpperdragon related items required pointing to his tindie site, and named the other parts appropriately so that they can be easily searched for and independently purchased. Once you understand the system it's actually pretty straight forward.

 

 

I also created a LumaCode System diagram that hopefully helps people to understand what is required.

 

 

If this looks accurate, feel free to copy and post it elsewhere. If I made a mistake, let me know and I'll correct and re-post the diagram.

 

EDIT: a lot of HDTV sets come with at least one USB connection, so likely the Raspberry PI ZERO could get its power from that.

[+mytek]

And from the Retro Hack Shack video "Crystal Clear HDMI For The Commodore 64 In 60 Seconds" I captured this image showing a diagram of the Atari 8-Bit LumaCode output revealing it's analog coded nature. Starting at the 4 minute mark, he describes the LumaCode concept for both the C64 and the Atari 8-BIT systems.

 

 

EDIT: Keep in mind that the video shows the separate analog board+the digital RGBtoHDMI board in use. This is not the same as COperdragon's RGBtoHDMI-LumaCode Pi Hat, which combines what is being done in 2 boards into one where LumaCode is concerned.

[macsonny]

Hi All,

 

Previously installed one of these in an Atari 800XL and I was super impressed with the image quality. So much so that I purchased another GTIAdigitizer for my Atari 130XE.

 

I previously had a VBXE and SAVO in my 130XE but we never 100% satisfied with the image quality. Removed those units and then installed the GTIAdigitizer by desoldering with GTIA, putting in a 40 pin socket, then replacing the GTIA into the GTIA digitizer and then soldering in a simple RCA female jack. All the exact same as I did for my 800XL.

 

Issue is the 130XE doesn't boot now - blank screen and doesn't even make the bumble bee startup noise. I actually swapped the whole GTIA chip and GTIAdigitizer across from my Atari 800XL just in case it was a faulty board or chip but nope, 130XE still fails to boot. I put eh GTIA digitizer and the GTIA from the 130XE into the 800XL and it worked fine, so not a faulty GTIA or GTIAdigitizer.

 

The only thing I can think is that I completely removed the RF modulator from the 130XE. Would that be the potential cause of the problem. I removed it when installing the VBXE/SAVO combination and the Atari worked fine but wondering if that might have something to do with it?

 

Any other ideas?

 

Picture of install attached. Ignore the wires hanging lose - they are from the SAVO install and not connected to anything.

 

Thanks

 

macsonny

 

 

[Beeblebrox]

53 minutes ago, macsonny said:

The only thing I can think is that I completely removed the RF modulator from the 130XE. Would that be the potential cause of the problem. I removed it when installing the VBXE/SAVO combination and the Atari worked fine but wondering if that might have something to do with it?

Unike the 800XL - which can still output a stock video output when the rf modulator is totally removed - when you remove it from the XE range you'll lose composite out for sure. I also thought you lost chroma and luma but that apparently isn't the case. 

 

With the gtiadigitizer I'd not expect you to have a problem. 

 

Have you followed the XE install here:

 

 

[macsonny]

16 minutes ago, Beeblebrox said:

Unike the 800XL - which can still output a stock video output when the rf modulator is totally removed - when you remove it from the XE range you'll lose composite out for sure. I also thought you lost chroma and luma but that apparently isn't the case. 

 

With the gtiadigitizer I'd not expect you to have a problem. 

 

Have you followed the XE install here:

 

 

Thanks for the info. I did follow that link other than I have completely removed the RF modulator but as you say, it shouldn't be a problem.

 

I'm staring to wonder if I have a failed SALLY chip as I swapped the GTIA and ANTIC into a working 800XL and they both showed working. I'm going to socket the SALLY tomorrow and try the SALLY from my working 800XL to see if that's the issue.

 

Any other ideas which I'm firing up the desolder machine?

 

[Beeblebrox]

11 minutes ago, macsonny said:

Thanks for the info. I did follow that link other than I have completely removed the RF modulator but as you say, it shouldn't be a problem.

 

I'm staring to wonder if I have a failed SALLY chip as I swapped the GTIA and ANTIC into a working 800XL and they both showed working. I'm going to socket the SALLY tomorrow and try the SALLY from my working 800XL to see if that's the issue.

 

Any other ideas which I'm firing up the desolder machine?

 

No worries.

 

A bad cpu would exhibit the issue you are experiencing so go for it. 

 

Don't put the known working cpu into the XE, do it the other way around. Just in case there is something with the XE that caused the cpu to die. Don't want to potentially damage the working cpu. 

[macsonny]

11 hours ago, Beeblebrox said:

No worries.

 

A bad cpu would exhibit the issue you are experiencing so go for it. 

 

Don't put the known working cpu into the XE, do it the other way around. Just in case there is something with the XE that caused the cpu to die. Don't want to potentially damage the working cpu. 

Ok. So after some more testing the CPU, ANTIC and GTIA are all working fine.

 

WHat's the next chip I should be testing?

[Beeblebrox]

2 minutes ago, macsonny said:

Ok. So after some more testing the CPU, ANTIC and GTIA are all working fine.

 

What's the next chip I should be testing?

Maybe it's the sockets, solder points vias and or traces to one or more of these chips. A magnifying glass, torch, multimeter continuity test are your next step IMHO, with all the socketed chips removed. 

 

I often shine a bright torch from the back of the pcb to see traces. 

 

Also, just to ask, when you power up with all chips in place, do you still get no indication of any audio? Not even any pops? Turn the volume right up. 

 

Are you also happy the is rom and or mmu are fine along with the ram? 

 

Anything can go at any time with these. Was the gtia socketing OK in terms of minimising the stressing of the board, vias, traces, etc. 

 

 

 

 

 

 

 

 

 

[macsonny]

25 minutes ago, Beeblebrox said:

Maybe it's the sockets, solder points vias and or traces to one or more of these chips. A magnifying glass, torch, multimeter continuity test are your next step IMHO, with all the socketed chips removed. 

 

I often shine a bright torch from the back of the pcb to see traces. 

 

Also, just to ask, when you power up with all chips in place, do you still get no indication of any audio? Not even any pops? Turn the volume right up. 

 

Are you also happy the is rom and or mmu are fine along with the ram? 

 

Anything can go at any time with these. Was the gtia socketing OK in terms of minimising the stressing of the board, vias, traces, etc. 

 

 

 

 

 

 

 

 

 

I've now tested both the POKEY and PIA as well. Both good. Desolder machine is getting a great workout!

 

Going to have a good look over the board to see if there is anything obvious.

 

Not getting any sound or video flicker but the GTIAdigitizer does take a few seconds to synch.

 

I'm fairly sure the RAM is ok because I replaced it a little while back to take the machine from a 64k to 128k machine and also replaced the GAL to allow the memory expansion.

 

GTIA was socketing ok. Did a bit of double checking and seems to be ok.

 

A few photos of the board to see of anyone can spot an obvious issue.

 

 

 

 

[macsonny]

Just to make things really weird, I get this screen even when the 130XE is powered down. Applying a little bit of pressure around the FREDDY causes the pattern to change.

 

What I want to stress is that POWER is turned OFF!!! However, I think there might be power applied to the board as the chips are getting warm. A short maybe?

 

Also getting a "click" on sound when powering up.

 

 

 

Edited December 31, 2023 by macsonny

[+Stephen]

15 hours ago, macsonny said:

Removed those units and then installed the GTIAdigitizer by desoldering with GTIA, putting in a 40 pin socket, then replacing the GTIA into the GTIA digitizer and then soldering in a simple RCA female jack. All the exact same as I did for my 800XL.

 

Issue is the 130XE doesn't boot now

The answer lies here.  The machine worked before you desoldered the GTIA.  You proved the GTIA works in another machine.  The problem lies in either the socket or the PCB.  Go over everything twice, three times, four times if necessary.  Use a magnifier and a lot of light.  The best way of testing, is to use a multi-meter on top of the socket, and trace it out to not the bottom of the PCB, but the other "end" of the trace.  This will test continuity through the PCB and socket.

 

I never like to think I mess up when desoldering.  I am usually great, but every now and then, there will be a hairline fracture, a busted pad, etc.

[+scorpio_ny]

I had a similar experience working with an 800XL. In my case, I simply removed the PCB from the case to do some additions. As part of the process, I powered it on before I begin making any changes. It did not boot up. After checking it, I discovered that by putting some pressure on the OS ROM chip, the computer would boot. What happened there was a bad/broken solder joint that was barely visible that had probably occurred because I flexed the motherboard PCB.

 

[macsonny]

Happy New Year everyone!

 

So did a bit more testing today. Full board inspection and found a few questionably joints which I reflowed.

 

Got the multimeter out and did a lot of continuity testing - all seemed ok.

 

Then I checked the voltage input leg of all the chips on the board. All of them getting 5VDC.

 

I checked the Vin and it's a good 5.1VDC.

 

Should I consider taking out the ROM to test?

 

 

 

 

[macsonny]

OS and BASIC chips removed and tested in 800XL. Both work fine.

 

I really don't want to desolder the FREDDY if I can avoid. Could it be the source of my issues?

[dabone]

Grab the schematics for the 130xe.

 

Check every leg of the gtia on BOTH sides. i.e. where it comes from and goes to.

I had a similar issue where I thought every thing was fine, and it was, from one side of the chip.

 

 

[macsonny]

On 1/1/2024 at 4:20 PM, dabone said:

Grab the schematics for the 130xe.

 

Check every leg of the gtia on BOTH sides. i.e. where it comes from and goes to.

I had a similar issue where I thought every thing was fine, and it was, from one side of the chip.

 

 

I started doing some track buzzing starting from the GTIA. I'll track seem to be fine but there is one labeled O2 (PIN 30) that does'n seem to have connectivity to another O2 point on the board. Even more interesting, when I check the O2 from FREDDIE (PIN 5) to the SALLY O2 pin (PIN 39) there is also no continuity.

 

This seems very odd to me.

 

FYI my mono assy no is CA200519.

 

Any thoughts?

 

[dabone]

Just run a jumper to the next place it needs to go.

 

And check every chip you have socketed / replaced

 

Edited January 4 by dabone

[Beeblebrox]

Have a quick question.

 

I have an Ntsc Chelco made 600xl. I am UK based and have been meaning to convert it to PAL.

 

Given the ntsc 600xl boards are missing the din5 monitor jack,  I added that in 2022. At the time I'd added some crude passive components just to get a stock video and audio signal out on the din5, albeit with the machine still running as an ntsc.

 

I had plans to convert to pal (usual process of swapping out the system clock chip, Gita and antic for pal versions of each, and adding in the pal colourburst.

 

For various reasons I didn't complete it and I've since removed the passive components involved in hooking up the din5, so it's been sitting around gathering dust.

 

Then with the arrival of the gtiadigitizer, and all the required pi equipment, etc, which I've bought to test in other A8, I wondered if I could use it in this 600xl, where I do the following:

 

swap out the ntsc sys clock, Gita and antic for pal versions

add in the gtiadigitizer and hook up the usual with the pi equipment, etc

 

Where my understanding is lacking is the following. Because I don't need the pal video circuit, I am assuming there is no need to add in passive components usually present in a pal 600xl for the video circuit, and also no need for the pal colourburst crystal....since the video signal is being taken directly from the gtia chip via the gtiadigitizer?

 

 

 

 

Edited January 7 by Beeblebrox

[+mytek]

15 hours ago, Beeblebrox said:

Where my understanding is lacking is the following. Because I don't need the pal video circuit, I am assuming there is no need to add in passive components usually present in a pal 600xl for the video circuit, and also no need for the pal colourburst crystal....since the video signal is being taken directly from the gtia chip via the gtiadigitizer?

Hmm... that does need to be determined. Keep in mind that the PAL colorburst is present on one of the GTIA pins. I don't know if the GTIAdigitizer references that or not as part of its conversion process.

[+scorpio_ny]

Hi @Beeblebrox,

 

I do not know if you recall, it seems that @dabone did what you are looking to achieve. See the thread Swapping ANTIC in NTSC to run PAL software, using Lumacode

[dabone]

I converted my NTSC 800XL to PAL by swapping the ANTIC/GTIA/and main crystal, Color works using the GTIADigitizer with only those components swapped.