+-^CrossBow^- Posted July 13, 2021 Share Posted July 13, 2021 9 hours ago, juansolo said: I'm a little concerned about heat with the speaker on the TIA & RIOT... I told you things get toasty in the 7800 LOL!. There is a reason I mount the UAVs on the BIOS or video ram chips after all if I'm keeping the RF intact. However, as I'm sure you have found out by now, the main heat generator is the 7805 followed by the 6502. The TIA and RIOT really start to get cooking when playing 2600 stuff. They get mildly warm when playing 7800 games. Also why I had expressed some concerns about the initial lack of ventilation on PMP's 7800 case design. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 14, 2021 Author Share Posted July 14, 2021 We used a 6k8 resistor and ran it to where the other two resistors are (done @-^CrossBow^- / UAV stylie). Volume seems pretty nicely balanced at about 1/2. Works really rather neatly and nicely. Not much else to say about this. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 15, 2021 Author Share Posted July 15, 2021 (edited) Let's play Spot The Difference! Above before, below after (ignore the colour inconsistency and it being a little out of focus, it's not that) Before above, after below. Details to follow when we've made it a bit nicerer. There's still some tweaking to do (we've gone slightly too far), but it proves the theory. We should be able to get it spot on. Scratch that, variable tweakage probably won't work. We'll just have to accept that it's a little bit of a compromise. Edited July 15, 2021 by juansolo Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 15, 2021 Author Share Posted July 15, 2021 (edited) So close! This might be as good as it gets... Edited July 15, 2021 by juansolo 2 Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 16, 2021 Author Share Posted July 16, 2021 (edited) What the above pics show is Cleggy proving his theory regarding the colour fringing. In that he was convinced it was a timing mis-match between the luma and the chroma. Initially we hard-wired the OR gate on the luma lines as the 74AHCT32 has a 5ns propogation time, essentially speeding that up to 0ns (we also tried a different IC that was 10ns). That made no noticable difference. So he went the other way and put a 4050 on the Maria chroma line and though a bit of experimentation, ran it through 6 of the gates on it. Each gate is 55ns so 330ns of shift. The actual perfect setting is somewhere between 5 gates and 6 on my machine (probably around 300ns), but it was better on the latter and we can only move in 55ns increments. It's a super simple circuit and I'll make it pretty at the weekend and take a picture of the installation. What it means is the colour fringing that was super apparent on Frenzy and Dungeon Stalker is pretty much eliminated. I can see it has gone fractionally the other way on some other colours on the colour chart above. But that's way less noticable in games. So this is a really rather lovely compromise. The picture is now insanely good. We'll mess with a PAL machine at some point also, but that's for the other thread. Edited July 16, 2021 by juansolo 5 Quote Link to comment Share on other sites More sharing options...
marauder666 Posted July 16, 2021 Share Posted July 16, 2021 Tried it in the PAL 7800, made no difference to the issues with the colours rolling. Although an old RCA 4050 from 1983 is so slow the monitor thought the colour signal was SECAM. Think this came out of Juansolo's 800XL. A Toshiba TC4050 from a 130XE and a "F" brand (Fairchild, Fujitsu?) 1982 CD4050 from my 600XL both work as expected. Quote Link to comment Share on other sites More sharing options...
+DrVenkman Posted July 16, 2021 Share Posted July 16, 2021 Wow, that's some great sleuthing! ? Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 16, 2021 Share Posted July 16, 2021 8 hours ago, juansolo said: What the above pics show is Cleggy proving his theory regarding the colour fringing. In that he was convinced it was a timing mis-match between the luma and the chroma. Initially we hard-wired the OR gate on the luma lines as the 74AHCT32 has a 5ns propogation time, essentially speeding that up to 0ns (we also tried a different IC that was 10ns). That made no noticable difference. So he went the other way and put a 4050 on the Maria chroma line and though a bit of experimentation, ran it through 6 of the gates on it. Each gate is 55ns so 330ns of shift. The actual perfect setting is somewhere between 5 gates and 6 on my machine (probably around 300ns), but it was better on the latter and we can only move in 55ns increments. It's a super simple circuit and I'll make it pretty at the weekend and take a picture of the installation. What it means is the colour fringing that was super apparent on Frenzy and Dungeon Stalker is pretty much eliminated. I can see it has gone fractionally the other way on some other colours on the colour chart above. But that's way less noticable in games. So this is a really rather lovely compromise. The picture is now insanely good. We'll mess with a PAL machine at some point also, but that's for the other thread. Hmm... I've these parts on hand to wire one of these up on mine. Now if only we could get the colors to look right for tower toppler through composite output... BTW it doesn't do any good to invert the UAV colors as you can with 5200s and 8-bits as that just results in no picture at all when you do that when I tried that last. Once this has been tested on a few more setups, it would be really ...like really good to forward this over to @MacRorie to see about it being implemented into the UAV. I know there are SMD variants of the 4050 as Bryan was looking into adding one anyway to the UAV to help with 5200 configurations. This would now give the 4050 more purpose than just the 5200 side since it could be used for the 7800 as well. To confirm, the Maria chroma out from this board goes into the maria chroma in on the UAV correct? Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 16, 2021 Author Share Posted July 16, 2021 (edited) 42 minutes ago, -^CrossBow^- said: To confirm, the Maria chroma out from this board goes into the maria chroma in on the UAV correct? Yup. If it goes too far, you can just tap the signal from the output of the 5th gate in the chain (just follow the links back from the output). We've only got one NTSC 7800 (for now...) to experiment with so no idea on how big a variance there will be between machines. You'd have to do some reshuffling on the UAV to implement it as the secondry colour input is the TIA colour. That said, I don't see any reason it couldn't just be renamed. Depends what the UAV is doing with the signals afterwards... But you wouldn't want it on the main colour input as that'd knock everything else out. EDIT: ...and re-looking that the IC, I could have done the vero layout with 2 links in total as there's no reason to use the gates in order. Bah! Edited July 16, 2021 by juansolo Quote Link to comment Share on other sites More sharing options...
+MrZarniwoop Posted July 16, 2021 Share Posted July 16, 2021 1 hour ago, -^CrossBow^- said: Now if only we could get the colors to look right for tower toppler through composite output For what it's worth, the UAV 7800s you did for me play Tower Toppler with proper colors over composite video to a couple different TVs with composite and with a RetroTink 2X-MINI. Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 16, 2021 Share Posted July 16, 2021 (edited) 9 minutes ago, MrZarniwoop said: For what it's worth, the UAV 7800s you did for me play Tower Toppler with proper colors over composite video to a couple different TVs with composite and with a RetroTink 2X-MINI. Are you sure about that? If they do, then it must only work on CRTs because composite on Tower Toppler with UAVs on an LCD looks all kinds of wrong. I'm not talking about the stripes you get using s-video, I'm talking about the artifacting effect not working properly through composite on this game. No amount of adjustments that I've been able to do, have been able to correct it on mine at least. 51 minutes ago, juansolo said: Yup. EDIT: ...and re-looking that the IC, I could have done the vero layout with 2 links in total as there's no reason to use the gates in order. Bah! So then technically, only the +5 on pin 1 is needed, a link on pin 3&4, GND on pin 8, Link on pin2 & 14, Maria out on pin 15, and Maria in on pin 9? Plus the 100nf cap on +5 and gnd (Bypass). Edited July 16, 2021 by -^CrossBow^- Corrected my pin counts Quote Link to comment Share on other sites More sharing options...
+MrZarniwoop Posted July 16, 2021 Share Posted July 16, 2021 1 minute ago, -^CrossBow^- said: Are you sure about that? If they do, then it must only work on CRTs because composite on Tower Toppler with UAVs on an LCD looks all kinds of wrong. I'm not talking about the stripes you get using s-video, I'm talking about the artifacting effect not working properly through composite on this game. No amount of adjustments that I've been able to do, have been able to correct it on mine at least. I'll take pics over the weekend and you can tell me if it's right. I don't have easy access to a CRT. Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 16, 2021 Share Posted July 16, 2021 5 minutes ago, MrZarniwoop said: I'll take pics over the weekend and you can tell me if it's right. I don't have easy access to a CRT. Just compare it with emulation screen shots captured here. I recall those being pretty accurate to what I remember through RF. Or...just compare how it looks through RF on a CRT vs the composite from the UAV on a CRT or LCD. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 16, 2021 Author Share Posted July 16, 2021 (edited) 45 minutes ago, -^CrossBow^- said: So then technically, only the +5 on pin 1 is needed, a link on pin 3&4, GND on pin 8, Link on pin2 & 14, Maria out on pin 15, and Maria in on pin 9? Plus the 100nf cap on +5 and gnd (Bypass). The layout above is because I tend to proto on vero so think in rows, links and cuts. So if you just want to wire it up to the IC (how we tested it) you'd need to do the following: Power on pin 1, ground pin 8. 100n cap between pin 1 and 8. Chroma in on pin 9. Link pin 7 to pin 10. Link pin 6 to pin 11. Link pin 5 to pin 12. Link pin 3 to pin 4. Link pin 2 to pin 14. Chroma out on pin 15. Edited July 16, 2021 by juansolo 1 Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 16, 2021 Share Posted July 16, 2021 32 minutes ago, juansolo said: The layout above is because I tend to proto on vero so think in rows, links and cuts. So if you just want to wire it up to the IC (how we tested it) you'd need to do the following: Power on pin 1, ground pin 8. 100n cap between pin 1 and 8. Chroma in on pin 9. Link pin 7 to pin 10. Link pin 6 to pin 11. Link pin 5 to pin 12. Link pin 3 to pin 4. Link pin 2 to pin 14. Chroma out on pin 15. Got it. The perfboards I use are all separate vias so I have to wire in cut leads for my traces, usually on the bottom solder side when I do this kind of stuff. But I think I have thin enough leads to put into the vias and still be able to press the IC legs into the vias along with them from the top side. That way my leads would be under the IC package between the PCB and the IC and be hidden in that case. Eitherway, you have quite curious to check this out on my 7800 soon. After that, it might give me a reason to learn Kicad or something to have a proper PCB made up for this and start adding it as a default option in 7800 UAVs going forward, or to retrofit into other 7800s I've done in the past. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 16, 2021 Author Share Posted July 16, 2021 49 minutes ago, -^CrossBow^- said: Got it. The perfboards I use are all separate vias so I have to wire in cut leads for my traces, usually on the bottom solder side when I do this kind of stuff. But I think I have thin enough leads to put into the vias and still be able to press the IC legs into the vias along with them from the top side. That way my leads would be under the IC package between the PCB and the IC and be hidden in that case. Eitherway, you have quite curious to check this out on my 7800 soon. After that, it might give me a reason to learn Kicad or something to have a proper PCB made up for this and start adding it as a default option in 7800 UAVs going forward, or to retrofit into other 7800s I've done in the past. Will be interesting to see how it does on yours. Obv we've only got the one and analogue being analogue, they're not all going to be the same. FWIW the 330ns delay, even though if I'm being hyper critical isn't quite spot on, in games, it looks damn near perfect. It'd certainly be a nice easy starter project for KiCad in terms of simplicity if you decide it's worth doing (it absolutely is IMO, but then I'm a bit of a PQ obsessive). Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 17, 2021 Author Share Posted July 17, 2021 Well it's a little busy in this corner now I will do a layout for the DIY board that will essentially be the chroma shift + chroma switching into our S-Video/Composite out. We're trying to get some more NTSC 7800s for more experimentage in that regard. With regard to the UAV the switching just isn't required and you could add the simple chroma shift between the Maria chroma out and the colour in of the UAV. I was going to say this machine is done, but it's going to get a BIOS swap at some point, so not quite yet... I've taken a lot of pics of output on CRT and LCD panel. The CRT looks incredible, it's borderline RGB good looking. Via Composite through an adapter rather than using the UAV's Composite out (just easier to do with this install), it obviously softens things but still looks surprisingly good. On the LCD you can tell it's S-Video, it's pretty good, but it's not a patch on the CRT image. 7800 NTSC Colour on 14" PVM CRT We're set a little bit off on colour because it looks more like PAL colours (it's kinda like the 'warm' setting on Mister) 7800 NTSC Colour 14" Sony LCD 2600 NTSC Colour 14" PVM CRT 2600 NTSC Colour 14" Sony LCD Now the 2600 is also a fraction out and I know we could fix that going through either one or two gates on the TIA chroma line. But it's nowhere near as annoying as it was on the 7800 so I'm not going to bother. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 17, 2021 Author Share Posted July 17, 2021 (edited) Some better quality CRT photos: Galaxian on CRT via Composite adapter: Edited July 17, 2021 by juansolo 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 17, 2021 Author Share Posted July 17, 2021 Lastly we've got LCD, which is not as good, but here for comparison: Galaxian via Composite adapter on LCD: Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 17, 2021 Share Posted July 17, 2021 @juansolo Mr. Solo... Impressive... very impressive work! I need to learn Kicad and get a batch of PCBs made up and order up some 4050s for UAVs in 7800 going forward. Direct capture: 7800_demo.mp4 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 18, 2021 Author Share Posted July 18, 2021 That's good that the shift seems to be about the same on two machines so it might be in the same ballpark across the board. Means this is a likely fix to the seemingly inherent drift. Gotta give all the kudos to Cleggy though (@marauder666) as it was him that had the theory that it was a timing mismatch and indeed did all the testing on this. I just supplied the test system, did a couple of vero layouts and made it pretty. Also need to address that at one point I said that I thought the chroma out was analogue when @SainT mentioned it was digital. He is of course quite correct otherwise the above wouldn't have worked! Quote Link to comment Share on other sites More sharing options...
marauder666 Posted July 18, 2021 Share Posted July 18, 2021 @-^CrossBow^- is that a current production TI CD4050, if so that's good. Easily available. Quote Link to comment Share on other sites More sharing options...
+-^CrossBow^- Posted July 18, 2021 Share Posted July 18, 2021 Yes it is new production. I just bought some from console5 I believe sometime last year. So yes, they are available. Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 18, 2021 Author Share Posted July 18, 2021 (edited) ...and this thread may continue as the flukey get that is Cleggy, has managed to snag two more NTSC 7800's for less than I paid for my one. Usual fun and games to ensue: will they make it intact? do they work? etc. I guess I'd better get my finger out and do that vero layout for the full NTSC mod. At least one of them will get that, the other probably a UAV+ChromaShift. EDIT: well this is unverified currently, and I'll likely have made a mistake, but it's probably pretty damn close to being right... Edited July 18, 2021 by juansolo 1 Quote Link to comment Share on other sites More sharing options...
juansolo Posted July 18, 2021 Author Share Posted July 18, 2021 (edited) Yep, there's a big chunk of it missing... I'm a plonker! I'll get back to this another day when it's not so hot. Edited July 18, 2021 by juansolo 1 Quote Link to comment Share on other sites More sharing options...
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