Dionoid Posted June 17 Share Posted June 17 I've heard something about CDFJ++, which apparently can be dumped by the Atari 2600+ and can play on that device. @batari @SpiceWare @johnnywc Anyone got more details on CDFJ++? Link to comment Share on other sites More sharing options...
+batari Posted June 18 Share Posted June 18 No more details yet - the conversation is ongoing. 1 2 Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 18 Share Posted June 18 Why '++'? Does '+' exist already? Link to comment Share on other sites More sharing options...
+wavemotion Posted June 18 Share Posted June 18 40 minutes ago, Thomas Jentzsch said: Why '++'? Does '+' exist already? Yes. And it's the bane of StellaDS mainly due to the optional features of LDX # and LDY # as fast fetchers (less so due to the much larger ROM/RAM space). But you must have known that as Stella implements CDFJ+ 1 Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 18 Share Posted June 18 6 minutes ago, wavemotion said: But you must have known that as Stella implements CDFJ+ Looks like I lost track of all the versions. 1 Link to comment Share on other sites More sharing options...
+Nathan Strum Posted June 18 Share Posted June 18 2 hours ago, Thomas Jentzsch said: Looks like I lost track of all the versions. I'm waiting for CDFJ+ Platinum. 1 Link to comment Share on other sites More sharing options...
+johnnywc Posted June 18 Share Posted June 18 On 6/17/2024 at 4:36 PM, Dionoid said: I've heard something about CDFJ++, which apparently can be dumped by the Atari 2600+ and can play on that device. @batari @SpiceWare @johnnywc Anyone got more details on CDFJ++? The "CDFJ++" is something I came up with, but it really is meant to be CDFJ+ rev2 or something like that. I proposed that we modify the existing CDFJ+ driver to support the copy memory feature that is in DPC+ that @batari leveraged to allow the 2600+ to dump DPC+ games. I am releasing Tutankham Arcade in a few months and it uses CDFJ+ and my hope was that some sort of update to the driver could be made before it's released so it can be more easily dumped by the 2600+. 3 hours ago, Thomas Jentzsch said: Looks like I lost track of all the versions. In your defense TJ, it was myself and @SpiceWare that made the changes to Stella to support CDFJ+ LDX/LDY fastfetch and the configurable data stream offset so that's probably why it didn't ring any bells. 🔔 Link to comment Share on other sites More sharing options...
+johnnywc Posted June 18 Share Posted June 18 13 hours ago, batari said: No more details yet - the conversation is ongoing. Hey Fred - we should touch base and see if we can figure out a way to get Tutankham Arcade running on a 2600+ *before* I release it and if there is anything we can do to the driver/source code to make it easier. Let me know if there's anything I can do to help! I have a 2600+ and Tutankham Arcade ROMs; the only thing I lack is the knowledge of how to change the CDFJ+ driver. 2 Link to comment Share on other sites More sharing options...
+SpiceWare Posted June 19 Share Posted June 19 I'd like to finally get the 60 Hz / 70 Hz issue resolved. We're also looking into rereleasing Draconian, and I'd love to have it support the 2600+. Considering the larger ROM size, I could see increasing the size of the CDFJ driver if we need to, doesn't need to be a full 1K, could be 256 or 512 bytes. 2 Link to comment Share on other sites More sharing options...
+batari Posted June 19 Share Posted June 19 Well, without revealing confidential information that I am privy to, I can say the following: Although current CDFJ carts can be supported, there is no way to dump arbitrary CDFJ carts. Basically, every individual CDFJ ROM needs its own individual implementation in the dumper. While this can theoretically be done in many cases, it is certainly not sustainable going forward. So as John said, we are looking at changing the CDFJ driver(s) to allow them to be supportable using a general method, so all future carts will work without having to expressly add each and every one. Sorry if I am being vague, but y'know, confidential information Anyway, I may have figured out a way to modify the CDFJ driver(s) to be supportable without using up any extra space. I'm doing some experiments with it now. 3 Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 19 Share Posted June 19 2 hours ago, batari said: Sorry if I am being vague, but y'know, confidential information Huh? Can you tell who is forcing you to act like this? BTW: I do not like more of this creeping into our hobby. 1 Link to comment Share on other sites More sharing options...
+batari Posted June 19 Share Posted June 19 Yes, I know who, and their initials are N.D.A... and I guess it's less of a "who" and more of a "what"... Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 19 Share Posted June 19 Well, some "who" requested you to sign the "what", right? And these requests are what worries me. Why would there be an NDA for homebrew drivers? I can only think of monetary interests (correct me if I am wrong). And again it would be money that spoils the fun (at least for me). Link to comment Share on other sites More sharing options...
+batari Posted June 19 Share Posted June 19 34 minutes ago, Thomas Jentzsch said: Well, some "who" requested you to sign the "what", right? And these requests are what worries me. Why would there be an NDA for homebrew drivers? I can only think of monetary interests (correct me if I am wrong). And again it would be money that spoils the fun (at least for me). It's for the 2600+, not CDFJ drivers. Of course I can talk about the new CDFJ driver itself. All I am doing with that is making essentially the entire ROM "visible" to the console so that future carts can easily be read by the 2600+. As for how existing CDFJ games will work on the 2600+, that gets into the algorithms in the 2600+ firmware and I think discussing that publicly may be verboten. 1 Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted June 19 Share Posted June 19 1 hour ago, batari said: It's for the 2600+, not CDFJ drivers. Of course I can talk about the new CDFJ driver itself. All I am doing with that is making essentially the entire ROM "visible" to the console so that future carts can easily be read by the 2600+. OK, as long as no NDA based secrets are creeping into Stella, this should be fine. 1 hour ago, batari said: As for how existing CDFJ games will work on the 2600+, that gets into the algorithms in the 2600+ firmware and I think discussing that publicly may be verboten. Well, if you make the entire ROM "visible", then there is not much secret left. 1 Link to comment Share on other sites More sharing options...
+Nathan Strum Posted June 26 Share Posted June 26 On 6/18/2024 at 7:34 PM, SpiceWare said: I'd like to finally get the 60 Hz / 70 Hz issue resolved. We're also looking into rereleasing Draconian, and I'd love to have it support the 2600+. Considering the larger ROM size, I could see increasing the size of the CDFJ driver if we need to, doesn't need to be a full 1K, could be 256 or 512 bytes. I'm still not exactly clear what the issue is with this - is it that we need to run certain games on the Melody board at 70MHz, but it doesn't work? Or doesn't work on some carts? Is this a chip issue? A driver issue? Is it even a solvable issue? I know this is holding up Zeviouz at the moment too, and I think it had an impact on some of the Turbo carts John shipped (but he could better speak to that). I'm not a developer (and I don't even play one on TV), but I'm actively involved in helping to get some of the affected games published, and I feel there's a mounting sense of frustration over this. Respectfully, - Nathan Link to comment Share on other sites More sharing options...
+SpiceWare Posted June 26 Share Posted June 26 2 hours ago, Nathan Strum said: I'm still not exactly clear what the issue is with this - is it that we need to run certain games on the Melody board at 70MHz, but it doesn't work? Or doesn't work on some carts? Is this a chip issue? A driver issue? RL's kept me busy so I still need to review the CDFJ+ discussions, but if I recall correctly: There's 2 startup routines in CDFJ+: Launched via Harmony Menu Flashed onto Melody board The Menu startup routine does not do anything to the MHz, so it's left at the 70 MHz that the Harmony Menu boots up at. When flashed to a Melody board, the CDFJ+ driver specifically sets it to 60 MHz. Routines will take about 16% longer time to execute at 60 MHz vs 70 MHz. For some games that's OK, but for others Vertical Blank and/or Overscan routines will take too long to run, resulting in screen jitter and/or roll. I think there was a chip issue that limited it to 60 MHz, but other chips are now available that can handle 70 MHz. The existing supply of 60 MHz chips can be used for batari BASIC DPC+ games, as they don't need the extra 10 MHz. If this is correct, then the Melody startup sequence needs to set the board for 70 MHz. If that's not correct then the Menu startup sequence should set the board to 60 MHz so we have proper results when people test play on a Harmony Cart. 1 Link to comment Share on other sites More sharing options...
+batari Posted June 28 Share Posted June 28 You are correct on most of these points. However, in practice the speed difference in 70 vs 60 is smaller because when running at 60 Mhz I've been successfully using fewer flash wait states so the actual difference is less than 16%. Link to comment Share on other sites More sharing options...
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