Heaven/TQA Posted January 2, 2019 Share Posted January 2, 2019 just some small test of my old 3d engine... does this work on real hardware? 3d1_7800.a78 8 Quote Link to comment Share on other sites More sharing options...
+SmittyB Posted January 2, 2019 Share Posted January 2, 2019 It works just fine on my PAL machine via a Mateos cart. Very nice! This sort of 3D always reminds me of the 'Artefacts' C64 demo. Quote Link to comment Share on other sites More sharing options...
LimitZer0 Posted January 3, 2019 Share Posted January 3, 2019 Very cool. I wish I had a flash cart to try this on. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 3, 2019 Author Share Posted January 3, 2019 Question: assuming the DLL and DLs remain static... why do I need to put them into RAM and not ROM? Quote Link to comment Share on other sites More sharing options...
+SmittyB Posted January 3, 2019 Share Posted January 3, 2019 I'd think it's just a question of different access times between the chips on the board. As far as I'm aware there's no real reason you couldn't put them in ROM, but somebody more technical might be able to say if there is. Quote Link to comment Share on other sites More sharing options...
Greg2600 Posted January 3, 2019 Share Posted January 3, 2019 Very cool. I wish I had a flash cart to try this on. Ditto Quote Link to comment Share on other sites More sharing options...
Trebor Posted January 3, 2019 Share Posted January 3, 2019 If trying under an NTSC console, keep in mind the demo is designed for a PAL system. Under an NTSC console, the display is shifted down, resulting in the bottom portion cut significantly. Additionally, under NTSC, the melody does not playback at the desired tempo. Here's some quick, raw, unedited footage: https://www.youtube.com/watch?v=cu2mWmuLQfY Thanks to CPUWiz and his MCP DevCart creation for the experience of trying it on hw. For those without the hardware to try, the demo plays as expected for the respective PAL and NTSC regions under the A7800 emulator. 3 Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 3, 2019 Author Share Posted January 3, 2019 thanks... holly shit... looks good on real metal . just some more testing... btw... does 7800 have a NTSC/PAL flag to test like GTIA? 2 Quote Link to comment Share on other sites More sharing options...
RevEng Posted January 4, 2019 Share Posted January 4, 2019 The DL/DLL RAM requirement is there, as SmittyB surmised, because the console RAM can be read by Maria quicker (in-spec) than ROM. If they allowed for ROM, we'd have worse DMA penalties. btw... does 7800 have a NTSC/PAL flag to test like GTIA? Nope. For PAL/NTSC detection in 7800basic, I basically count the number of lines in the visible screen. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 4, 2019 Author Share Posted January 4, 2019 but in A7800 I can put DLL and DL into ROM? so it's possible for static stuff... even I suffer more cycles DMA Maria is demanding? Quote Link to comment Share on other sites More sharing options...
RevEng Posted January 4, 2019 Share Posted January 4, 2019 a7800 (or any other emulator) isn't modelling the access speed limits for mask ROM/EPROM vs RAM. I don't believe Maria will actually adjust the DMA timing dynamically like that, it will just access ROM faster than spec. If you do it on real hardware, it might even work on some consoles, and fail on others. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 4, 2019 Author Share Posted January 4, 2019 Baaaah thats shit.... if thats true why does every emulator suffer??? I read it in your dev wiki but thought I test it in a7800.... and it worked... I mean putting every stuff into that small 4K ram is not good..... Quote Link to comment Share on other sites More sharing options...
RevEng Posted January 4, 2019 Share Posted January 4, 2019 I read it in your dev wiki but thought I test it in a7800.... Yeah, the dev wiki says that in the "7800 Software Guide" section, from Atari+GCC. I've updated and corrected parts of the guide, but that part is original. a7800 is good, but 7800 homebrew history is littered with ROMs that worked in an emulator, and not real hardware. Since Atari says it won't work, I'd do a lot of testing on a bunch of real hardware before I used it in a game or demo. Quote Link to comment Share on other sites More sharing options...
TailChao Posted January 4, 2019 Share Posted January 4, 2019 For PAL/NTSC detection in 7800basic, I basically count the number of lines in the visible screen. Another option is to put a DLI out of range on an NTSC console but within a PAL frame length and see if that gets fired. Since Atari says it won't work, I'd do a lot of testing on a bunch of real hardware before I used it in a game or demo. The remark about putting Display Lists in ROM is purely an access time thing. I have no idea how slow the Mask ROMs used by Atari or GCC were, but anything 120ns or faster should be okay. Any NOR Flash you're buying nowadays should be this fast or better. It only becomes an issue if you're using PHI2 to gate accesses, since Maria's reads aren't necessarily aligned with it. But in that case it's only a problem for the cartridge hardware designer. Quote Link to comment Share on other sites More sharing options...
RevEng Posted January 4, 2019 Share Posted January 4, 2019 Glad you agree about access times being the issue. A lot of homebrew boards are designed to use vintage eproms, rather than modern NOR flash. No idea on the access times, but I don't think they'd outshine the mask ROMs. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 4, 2019 Author Share Posted January 4, 2019 So DL and DLL in RAM, right? Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 4, 2019 Author Share Posted January 4, 2019 Another option is to put a DLI out of range on an NTSC console but within a PAL frame length and see if that gets fired. The remark about putting Display Lists in ROM is purely an access time thing. I have no idea how slow the Mask ROMs used by Atari or GCC were, but anything 120ns or faster should be okay. Any NOR Flash you're buying nowadays should be this fast or better. It only becomes an issue if you're using PHI2 to gate accesses, since Maria's reads aren't necessarily aligned with it. But in that case it's only a problem for the cartridge hardware designer. The DLI test sounds nice.... is Maria cutting off too long DLLs or like on A8 picture gets corrupt and rolling? Quote Link to comment Share on other sites More sharing options...
TailChao Posted January 4, 2019 Share Posted January 4, 2019 A lot of homebrew boards are designed to use vintage eproms, rather than modern NOR flash. No idea on the access times, but I don't think they'd outshine the mask ROMs.Depends upon how vintage . Once we get towards the late 1980s and early 1990s, 120ns and faster EPROMs become pretty common. The 200ns - 250ns dinosaurs would be a problem though. So DL and DLL in RAM, right?Assuming a the cartridge's design and components are "modern" then anywhere you like, RAM or ROM. Just absolutely not in the RIOT's RAM. If you want some good snow effects, have Maria read that as graphic data. The DLI test sounds nice.... is Maria cutting off too long DLLs or like on A8 picture gets corrupt and rolling?She'll stop at the end of the frame, so if your DLL is too long the extra lines get cut off. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted January 4, 2019 Author Share Posted January 4, 2019 Eg Mateos card? Quote Link to comment Share on other sites More sharing options...
TailChao Posted January 4, 2019 Share Posted January 4, 2019 Eg Mateos card?I don't own this one (or actually any of the available flash carts), so I can't say 100%. But it looks like the MCP is fine from Trebor's test. Quote Link to comment Share on other sites More sharing options...
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