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TheProgrammerIncarnate

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About TheProgrammerIncarnate

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  1. The MARIA-related thread was last bumped in 2010 while this one was more recently active so I posted it here. The GTIA, MARIA, TIA are all in the same vein of Atari custom graphics chips. No biggie. I heard somewhere that Curt was hesitant to release files because he gave them to someone in the past who used them in something closed in proprietary. No idea if that is true or not. Anyway, he shared them with me and Alan S. (not on AA forums) because Alan was wanting to improve the 7800 core for the MiSTer project (an open FPGA emulation system) and because I've been working on automatically turning layout information into schematics/verilog in my own project. I agree 100% that they should be freely available, but I'll wait till Curt decides that they should be. Perhaps a GPL-esque license would ensure they are only used in open projects.
  2. Curt just released the schematics here. He also shared the GDS files with me in hope that I could help convert them to verilog. Unfortunately I've been unable to open them as they're an older format of GDSII files.
  3. Got the AY-3-8605 "Sea Battle" chip in a simulation and generating screenshots. I don't think there's been any form of emulation prior to this. https://nerdstuffbycole.blogspot.com/2019/10/shooter-game-in-silicon-inside-ay-3.html
  4. Hmm... The Odyssey 4000 apparently uses a AY-3-8600 game chip, with color from a AY-3-8615 chip. According to the databook (page 486) video out on the 8615 is pin #5, you tested this one, right? Besides that there are a few traces between the two chips, and the clock signal circuitry (if the game plays then the clock circuitry should be fine.) Also, what thread did you base your composite mod on? It may be that the 8615's outputs need amplification or adjustment before the TV can process them.
  5. Interesting observation! Perhaps one of the pins on the 10 game chip served to downgrade it to a regular Super Pong chip. So they could sell Super Pong & Super Pong 10 systems with the one chip once it came out.
  6. Here's the picture of the upper-right corner. I think I labeled all hidden/obscured parts. Also, the speakers are 0.2W, 8 Ohm for the record. Unfortunately I'm going to be away from home again so I won't be able to properly inspect those pots or inductors. Just mark them with "untested" for the time being. Also, I'm going to store the schematics in my 1st gen game system REing git repo, you won't mind as long as I credit you?
  7. Ok I confirmed the values of everything except stuff in the far upper-right. There's a close-up of that region, so I'll mark that picture instead as this one is blurry and has things in the way. A few things I wasn't able to confirm/find out values on: the two inducters/coils inside the modulator, the two inductors to the left of the power switch, and "L1" which appears to be a ferrite choke. None of these had values on or near them. Two of the dark brown film capacitors & a transistor inside the modulator were too tightly packed for me to read their values. The transistor is probably a standard or video-specific NPN, while the capacitors are probably "39" (nanofarads?) like all of the others of that type. Lastly the two blue pots don't have values on them and appear to have been set at the factory, as they've been glued in place. I also found the manual in slydc's archive, cleaned the controllers, and took some notes on the gameplay. That'll be useful for whenever I start looking at the AY-3-8700's die.
  8. Second picture? There's only one up there. I'll get back to you on the trim pot.
  9. Here's your picture with the values filled in. I just noticed that all of the green capacitors (except the small one in the upper right) are 0.1uF. Sorry for the late reply, I've been busy.
  10. The components are currently on a breadboard, so I used an alligator clip connected to the unmodulated video (blue circle), along with a pair connected to power/ground lines. I forgot to mention it earlier, but a decoupling capacitor should be added to the mod. Without it, the brightness fluctuates whenever the sounds play.
  11. Ok I messed around with the composite mod again and here's the results. I used a 470+100ohm voltage divider, plus a 100ohm resistor to match impedance (75ohm might be better, but I don't have any.) Schematic is below. On the digital TV it looks great, except for some noticeable vertical lines which are based on the clock frequency. On the CRT TV, the black components (right tank + mines) and grey background are hard to tell apart, the white areas also are not maximum brightness. But when I set the CRT's brightness to 100 (instead of 50) it looks perfect. Which is making wonder if the composite mod is good but the TV isn't.
  12. R71 is 100 ohms The capacitor under C50 is C38, I can't see anything except 33/16 & "Tracon" on them. They look like pre-speaker filters, which should limit their possible values. R7 is correct The transistor near Q3 is Q4, across from it is Q5 Q5 says "1702M P731" on it, while Q3 & Q4 say "MPS A13" Google says the 1702M is an audio transistor which would make sense. The mylar capacitors only say "1.50V" on them, so I'll have to test them along with the Tracon ones
  13. Here I added some more pictures to the ones I already took: https://drive.google.com/drive/folders/1wT2uEGUd0Weu8t7w5Pnv5nfFAgAe3Tmx?usp=sharing Just tell me which components you can't see properly and I'll look at them closer
  14. Huh, I wonder if someone tried repairing this unit before... Anyway, I'm back home now and can look at my Combat! unit + take pictures if that helps either of you.
  15. Sorry about that. A composite mod should still be pretty simple. This isn't night mode, the background appears black instead of grey (or maybe the white areas are "too white".) It actually looked fine when I plugged it into a modern TV. Again, I'm pretty sure this can be fixed with the correct resistor values.
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