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Everything posted by alex_79

  1. Mhmm... Something's not quite right. I erroneously got credit for "Playfield Timing" which is by Micheal Rideout (@SeaGtGruff) instead. And, there's no need to credit me at all. I feel that might cause people to refrain from correcting, editing or rewrite that page, which is the point of a wiki. There's always the page history if someone wants to see who contributed.
  2. I added a brief description about the Vertical Delay. I always found the Stella Programmer's Guide a bit confusing about this. Maybe it could be referenced when pages about the VDELxx registers are done. Perhaps my bad english will be an incentive for someone to register and fix it, and then add content to the tiki...
  3. Thank you! Compiling right now...
  4. The download links don't seem to work here. I get a 404 error for all of them except for the R77 one.
  5. related to this: https://atariage.com/forums/topic/167173-what-does-the-game-select-switch-actually-do/ https://atariage.com/forums/topic/192031-stella-35-released/?do=findComment&comment=2435332
  6. I think it would be better to also set SWCHA and SWCHB to 0, because, as i wrote in the other thread, those registers will keep the last value stored to them and use it when set to output. It's unlikely that this would cause issues, but in theory a game might (rightfully) rely on the fact that they're zero.
  7. You can write to SWCHA and SWCHB even if they're set as input and the RIOT "remembers" the value when you set them as output. That's one of those occurrences where the "Stella Programmer's Guide" describes the intended usage rather than the actual behaviour. In the 2600, port B is connected to the console switches, so it was meant to be used as input only. But that's a standard 6532, and the port is fully configurable. The 3 unused bits can be safely set as output and used as 3 bits of memory. "Combat" does that for example. Technically, you can set also the other bits as output, and reading them will always return the programmed value and not the position of the switches, but it has not been determined if it's safe for the chip in case you set a bit "high" while the connected switch is closed, that means the pin is shorted to ground. I remember this was discussed a few years ago in the forums.
  8. No, the reset sequence requires to pull RIOT pin 34 (/RES) low: On a 2600 this only happens when powering on the console. E.g.: this is from the 6-switch console schematic: After turning on the console, the /RES pin will initially be "low" until the capacitor (C220, charged through the resistor R217), will reach the voltage for a logic "1". Then it will just stay "high" as long as the console is powered on.
  9. Seems like there's no "search" function for non logged in users? What about a place for discussing improvements and ideas for the wiki pages and post or link documentation to be used as reference? I think a club here on AA ("behind the woodgrain"? 😄) would work perfectly for this.
  10. You need to initialize SWCHA, SWACNT, SWCHB and SWBCNT to 0 in the PlusCart menu. Those registers are automatically zeroed by the reset sequence of the 6532, so usually initialization isn't needed unless you need a different behaviour (e.g. for keyboard controllers, atarivox and other peripherals). But when using the "emulation exit" function instead of power cycling the console, the 6532 reset sequence doesn't take place, so there could be issues with the controllers and/or console switches if the rom that was running before set the RIOT ports to output.
  11. New Pluscart owner here! I've received today my DIY kit and it's up and running now! Very easy to assemble, the instructions are very detailed. I successfully connected to my WIFI using the joystick with the on-screen keyboard, and registered to the PlusStore. I modified an original case as per instructions and also did the "hotglue led lens" as suggested by @vitoco a few posts above (thanks for the tip!) Wonderful device! 👍
  12. Yes, you can remove all the 7 "extra" wires if you don't use that function.
  13. The problem is due to the "extra" button functionality of the RGB mod, intended to have an additional button on a modified joystick for remote "RESET" and "SELECT" switch. The way this is implemented interferes with some controllers (e.g. trackballs) and also with games that use the controller ports as output, as is the case with "Track and Field" (the game in fact briefly pulses the I/O pins low on each frame). The Testcart also uses the pins as output (to read the keyboard controllers), that's why you see the spurious "reset" switch presses there. The solution is to disable that functionality of the RGB mod, as suggested in this post: https://atariage.com/forums/topic/243453-atari-2600-trak-ball-games/?do=findComment&comment=4268807
  14. That's something I felt it was needed for quite some time, as there's so much info resulting from the last over two decades of homebrew scene that is hard to find because it is scattered all over the place. I hope many people will participate to add contents. 👍
  15. That's just because it was never officially released in PAL format. The slightly smaller palette isn't a big issue. You find a PAL60 version in the thread linked a few posts above and it looks like this:
  16. Is the problem with any game or just Spider-man? You need to press the fire button and then move the joystick up, left of right while still keeping the button pressed to shoot the web. The manuals for the games can be found on AtariAge (here's the on for spider-man), Atarimania, The Internet Archive and other places.
  17. I had some pictures of one of my Jr board on my PC (PAL-B, board CO21503, rev. F1). I've highlighted the traces going from the luma and Sync TIA pins to the CD4050, and they match J.Sobola's schematic: board (top) bord (bottom) You might be able to fix the mod with minor modifications, by removing all the jumper plugs and soldering short pieces of wire to connect the pins as in this picture. There's still the problem that with the CD4050 removed, the gate in the CPU reset circuit (circled in blue in the schematic) is missing. Since your console is still working without it, I guess it's not strictly necessary, but if it was me I'd follow @DrVenkman suggestion and I would remove the mod board, reinstall the CD4050, and then simply connect the mod using wires to the needed signals (those pullup resistors connected to the TIA pins are perfect for this). Verify that your board matches the one shown here by checking continuity between pins marked with the same colors. If it differs trace it to find the right spots where to pick the signals. Note that I'm not familiar with the UAV board as I never installed one myself, so use these info at your own risk!
  18. Load "Air Sea Battle", press reset to start the game and flip the TV type switch to B&W. The sky will show all 8 luma values in order from black to white. If there are less than 8 shades and/or if they out of order then the luma pins are not conencted correctly. BTW, is the CD4050 still on the board, with the mod pcb mounted on top of it, or has it been removed?
  19. Work perfectly on all my PAL consoles. Thanks for sharing!
  20. Check if a new serial port is detected when you plug the usb cable (you should see a new device, e.g. /dev/ttyUSB0). Also, try running the software as root. If it works that way, it's a permission issue. You need write access to the serial port.
  21. Yes, Jerzy Sobola's schematics are not official, so you should always verify the connections on the actual board you're working on, but they're a great reference noneless. There are different revisions of the schematics, too: I think those posted above are more recent than the ones in the AtariAge site. Also note that official PAL schematics for the 6 switch console can be found in the PAL service manual. Atari_2600_PAL_Service_Manual.pdf Anyway, (many) years ago I did a s-video mod on one of my junior consoles, and later on moved that same mod into a 6-switch (link). In both cases I tapped the signals from the CD4050 and the pinout matched Jerzy Sobola's schematics. Of course it's always best to double check, as there might be different board revisions. If you compare with the youtube video above, then yes, there are hues differences, but the video shows the color of the NTSC game running on a NTSC console. The PAL game on PAL console looks like this: It seems to me that colors are correct (considering a little variance due to the color pot adjustement) and the differences are indeed due to wrong luma connections. I don't know how this specific mod works, but if the LUM and SYNC are connected to a resistor ladder like in the Atari board, then I think swapping sync with one of the luma inputs could still produce a stable picture (the resistor value would be wrong, but the resulting signal might still be within tolerances).
  22. No, that adapter just connects two ranger controllers to provide both paddles in one port (just like standard paddles). There's not electronics inside, just wires.
  23. Is there a single jumpers configuration for use with any 2600 console? No surprise that it doesn't work. I don't know about NTSC versions, but the cd4050 is surely NOT wired the same in PAL 6-switch and PAL jr consoles. The inputs for the lum and sync signals are on different pins, and the remaining 2 inputs are used for different functions: on the 6 switch they buffer the joystick fire buttos, while on the Jr (PAL-B) one is part of the cpu reset circuit, while the other one is connected to the 4.43 Mhz oscillator circuit (but the relative output is unused). There's also a PAL-I jr that uses a different board and the pinout might be different there too. 2600-2600A-2600jr_PAL.pdf I would not power on that console until after tracing the board and fixing the connections, as there's the risk of damaging the mod board and/or the console itself.
  24. James is @ZeroPage Homebrew, and the RGB mod installed on the 6-switch consoles used for playing the games during the show on Twitch seems to introduce some glitches:
  25. Just to complicate things a bit, a few years ago when testing the early bus stuffing demos, I tried swapping the TIAs between my 6-switch and vader consoles but I still got the positioning issue on the 6-switch and not on the vader. So the TIA variation is not the (only) variable. Someday I should try installing one of the later TIA from my Jr or 7800 units into an older console. I don't know if anyone tried this before, as the later models have the IC which are soldered to the board, so removing them is not as easy as with older ones.
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