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About DirtyHairy

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  • Birthday 08/19/1980

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    Music, Guitar, Coding, Retrocomputing & Emulation, Computers & Technology in general, Books, Food, Family

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  1. Hmmm, maybe I broke something when I added sqlite. Thanks, I'll investigate...
  2. This is decidedly weird. Maybe the file was corrupted during writing, and Stella doesn't read it properly. The next beta will store per-game settings in sqlite and will save them immediately after they are changed.
  3. I second Thomas: this is an impressive number. A big "thank you" from my end to everyone involved, too!
  4. No, you can't. The hardware of the R77 is very different.
  5. I think that you can safely ignore the frame count for now. There is no strict definition of the boundaries of frames for the 2600, especially during the initialization phase of a ROM where no valid TV signal is generated. Stella has a pretty elaborate algorithm for determining the boundaries between frames that is built to address many special cases, and I am not surprised that your counting differs. The cycle count that a section of code requires to execute is an exact number, though, and if you step instruction by instruction, you should be able to track down where your emulation gets it wrong.
  6. I would assume that you still have one or two opcodes whose timing is off, and this causes the cycle shift you are observing. You can try to track them down by stepping the affected code in your debugger (provided you have already implemented one ) and comparing the instruction timing to Stella instruction by instruction until you find the faulty opcode. I am not sure whether I understand your question about WSYNC. Strobing WSYNC will pull the RDY line of the CPU low until the next HBLANK phase starts. Pulling RDY low will halt the CPU in the next read cycle. Unless you are close the the 76th cycle, the number of clocks that the strobing instruction requires to execute is irrelevant. The only possible twist concerns instructions with two consecutive write cycles (i.e. RMW instruction); as the CPU stops at the next read cycle, those will still cause the CPU to be suspend until the next HBLANK only (as opposed to skipping a fill line because of writing WSYNC twice).
  7. This definitely sounds like individual frames are not displayed. There is no frame skipping in Stella at the emulation level (I don't think that there is even a meaningful way to do this); the only situation where Stella may skip frames is if the video hardware cannot keep up with the emulated frame rate (for example, running a NTSC game on a 50Hz display). However, if this type of skipping happens, frames don't even enter the phosphor processing either, so the fact that turning on phosphor "fixes" the issue suggests that the skipping must happen outside of the Stella core. Sorry, this lies out of the scope of Stella.
  8. I am not aware of any varying revisions of the R77. Maybe try another SD card.
  9. At least you've got FA implemented now
  10. I can't test on hardware right now, but it looks like you found a Stella bug. Stellerator (see the link in my signature) and Stella share the TIA core, and Stellerator looks correct. I can get Stella to display correctly if I enter the debugger while the demo is running, reset the demo in the debugger and hit "run" again. Opened a bug on the Stella tracke here.
  11. Not all banking types support the extra memory atm, though: http://atariage.com/forums/topic/251202-3e-does-not-work-with-larger-rom-sizes/
  12. Yep; currently, no games that use the melody ARM work on the Unocard (DPC+ and CDF). In principle, it would be possible to run the same ARM code on the STM32 CPU used on the Unocard, but the memory map is different. I'd like to look at this at some point (I have managed to get DPC+ games running on the modified memory map in emulation by patching the binary), but I don't know if and when this will happen
  13. Galaga uses a new variant of the CDF banking scheme (CDFJ). The only emulators that currently support it are Stella 6.0.1 (and later) and 6502.ts / Stellerator. The R77 is based on the current Stella 6.1 codebase and will run it fine; the same holds true for the recently updated libretro core. As for cartridge emulators, only the Harmony cart can currently run the ROM (the necessary Harmony CDFJ driver is part of the ROM image).
  14. I've got a few The mega bitmap demo. This is very sensitive to the timing details of HMOVE. Meltdown is sensitive to the effects of changing NUSIZ during or close to drawing a sprite. I checked your emulator, and although all four rows of circles are drawn correctly, the half-images of the right two columns are off by a pixel or so (resulting in a "wobbling" effect). Both Realsports Boxing and Activision Grand Prix are sensitive to similar effects of NUSIZ. Watch for stray lines in the sprites that may appear depending on sprite placement. Mr. Roboto (a Bezerk hack by Paul Slocum) is sensitive to the precise timing of the RIOT Pole Position is sensitive to the exact timing of BRK. Failure to emulate it correctly will result in a shift of the road Snoopy and the Red Baron: many emulators have trouble with the landscape and clouds Edtris will work correctly on if reads from invalid addresses are emulated sufficiently well. Eshu's 32 char demos are very sensitive to RESP during draw. This Stella issue on github contains several test programs that test the accuracy of RIOT timer emulation This Stella issue has test code for the details of changing NUSIZ while drawing There's even more of this stuff here on AAge There's a bunch of tests that go into the details of collision handling during HBLANK here Even though there are some minor kinks, you already have pretty accurate TIA emulation Do you have the source of your emulator somewhere on the web?
  15. A pity about the performance, but still pretty cool.... Now Tesla should add at note not to play VCS games while on autopilot
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