Jump to content
stephena

Testing the new Stella TIA core

Recommended Posts

Small regression in the new core. Keystone Kapers shows some problems (ball positioning, I guess), resulting in black lines on the left edge.
post-10599-0-83374300-1483208482_thumb.pngpost-10599-0-11000800-1483208484_thumb.png

Edited by alex_79
  • Like 1

Share this post


Link to post
Share on other sites

Good catch. The code looks like this:

    sta RESBL     ; ends @00
    sta HMOVE     ; ends @03, HMBL = 22 

Share this post


Link to post
Share on other sites

That was a funny little bug. Actually, it wasn't so much a ball positioning issue, but an issue with the draw triggered by RESBL. According to Andrew Tower's notes, a draw is triggered immediatelly on hitting RESBL (while the other sprites will only draw when the counter wraps on the next line). The timing of RESBL is different during hblank, and it seems that the draw delay must be adjusted accordingly in this case. I had suspected so much before, but I wanted to wait for an actual testcase before implementing it.

  • Like 1

Share this post


Link to post
Share on other sites

Hi Eshu!

 

Ok - I think this one is a regression from the old core, but I've never run the binary on a real machine - someone might be able to now with a harmony encore? it's an EFSC rom, the menu pointer is made up of a missle, and is supposed to be two pixels wide, I think NUSIZ1 should get changed just in time.....on old Stella it shows up 2 pixels wide, but just 1 on the test release.

My harmony encore has arrived, and I have finally find time to check this on real hardware (I had to pad the image with two bytes in order to get it to run). You can find some pictures attached to to the github issue here: https://github.com/stella-emu/stella/issues/24

 

The new core seems to display this correctly. I am not sure about the additional dark pixels at the right edges of the objects; I think they are artifacts of HF (de)modulation, color bleeding and of our LCD's image processing; I'll recheck once I have my composite mod complete :)

Share this post


Link to post
Share on other sites

I haven't tried exotic switching formats yet on my Harmony Encore, but if it fails to auto-detect a format, I think you can name the file with the bank switch extension?

One of those things that Harmony does great is to detect all the bank switch formats that older cards had to use extensions or text lists, but I think it still retains the ability to set a bank switch from a file extension.

Share this post


Link to post
Share on other sites

I haven't tried exotic switching formats yet on my Harmony Encore, but if it fails to auto-detect a format, I think you can name the file with the bank switch extension?

One of those things that Harmony does great is to detect all the bank switch formats that older cards had to use extensions or text lists, but I think it still retains the ability to set a bank switch from a file extension.

Afaik, renaming the file indeed allows to override auto-detect. However, this didn't work here either. The cartridge image is two bytes short, and I guess that the driver checks the image length and refuses to load.

Share this post


Link to post
Share on other sites

The 4th test build is now available. This one basically brings parity to Stella 4.7.3 wrt the TIA. Of course is also improves things immensely, but there should be no further ROMs that worked in the old core and do not work in the new core. Please test and report !

  • Like 2

Share this post


Link to post
Share on other sites

Thanks for the update!

I just compiled it and will test in the next days.

 

A small note: it still says "stella 5.0.0-pre3" in the window title and selecting "about" in the menu!

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the update!

I just compiled it and will test in the next days.

 

A small note: it still says "stella 5.0.0-pre3" in the window title and selecting "about" in the menu!

 

Yep, we forgot to update the version in the tagged release source (the binary builds contain 'pre4').

 

Also, there is now an OSX build for pre4.

  • Like 1

Share this post


Link to post
Share on other sites

Thanks for the update!

I just compiled it and will test in the next days.

 

A small note: it still says "stella 5.0.0-pre3" in the window title and selecting "about" in the menu!

I have moved tag; if you refetch the tag and rebuild, you should get the correct version ;-)

  • Like 1

Share this post


Link to post
Share on other sites

I wonder whether the absence of feedback signals the absence of testers or the absence of bugs :) If you test and don't encounter any issues, would you mind a short post that all is well?

Edited by DirtyHairy

Share this post


Link to post
Share on other sites

Absence of testers.. unless reports come flooding in that say I've tested! I've tested!

 

I myself have run about 40 or so randomly chosen games in casual play. I have nothing to report.

 

---

 

I really hate to say it but the novelty of emulation like we had in the 1990's, the magic of running your old games on the PC, has toned down these past years. Or so it would seem if you listen to the vocal minority. And yet, today, we have some of the best efforts and results to date. Many of today's emu's are viable console replacements - and them some - with all their side tricks and amenities.

 

PC emulators picked up a stigma along the way of being hard to configure, not accurate, not fully compatible, "just off", frustrating, and in general not a nostalgic experience. And just "because PC." But that hasn't been true of the better ones for a long time.

 

Yet, emulation is actually becoming a premier way to play the classics today. The tide is turning. In a sleeper kind of way. The advantages that emulation offers both consumer and corporation *are* becoming evident. But enough of this for now. It'll all be in a book I just started called Principia Emulata.

  • Like 2

Share this post


Link to post
Share on other sites
Issue which occurs under Stella 5.0.0-pre4, but does not occur under real hardware or Stella 4.7.3:


Activision Grand Prix - Momentary scanline corruption, left side of screen, same row and color of opponent car:


post-18-0-91796100-1484789657_thumb.pngpost-18-0-17460100-1484789659_thumb.pngpost-18-0-66019000-1484789659_thumb.png

  • Like 1

Share this post


Link to post
Share on other sites

...ah! Another of the games in my personal library!

 

Oh, and nice Icon, Treb; you a Nostalgia Critic fan? Musta gotten that from his latest Commercial Special.

 

"YOU'RE RUNNING OUT OF FLU-WEED!!!!111"

 

;)

Share this post


Link to post
Share on other sites

Issue which occurs under Stella 5.0.0-pre4, but does not occur under real hardware or Stella 4.7.3:

Activision Ice Hockey - Occasional 'dot' appears on the left side of screen when puck is in the upper half of the rink; appears on the right side of the screen when puck is in the lower half of the rink. Imitates movement of puck momentarily then disappears:

post-18-0-67000800-1484795516_thumb.pngpost-18-0-20371300-1484795517_thumb.png
post-18-0-76354000-1484795517_thumb.pngpost-18-0-25481600-1484795518_thumb.png

Oh, and nice Icon, Treb; you a Nostalgia Critic fan? Musta gotten that from his latest Commercial Special.


Reminiscing of my younger years, did a search for Spider-man Atari commercial, and located it, took a capture. I remember the video details mentioning it was posted several years ago; don't recall the poster's name though.

  • Like 1

Share this post


Link to post
Share on other sites

I noticed Video Chess no longer has that black mark on the left side.

Good catch!

 

On my PAL TV I can see a ~2 pixel blue line which extends from the right into the black (HMOVE) area on the left. I cannot see the blue line on the left and the black line.

Share this post


Link to post
Share on other sites

M-Network games seem to reset differently.

 

Example: Space Attack (1982) (Mattel).BIN

Older versions of Stella blank the screen to black while the reset key is held.

Pre-release 4 chops the top 1/4th of the screen off, makes the other 3/4th's flicker, and upon release of the reset key restores the image and makes it bounce 1 time. Don't know which the correct behavior or if this is important or not.

 

Seems different M-Network games behave differently when resetting them.

 

Maybe this is not a problem?

Share this post


Link to post
Share on other sites
Issue which occurs under Stella 5.0.0-pre4, but does not occur under real hardware or Stella 4.7.3:


Atari's Midnight Magic - Vertical line glitch near the lower left side of the pinball machine:


post-18-0-02161300-1484864708_thumb.png

  • Like 2

Share this post


Link to post
Share on other sites

Oops, that's what we get for asking for more bug reports; the list of bugs doubled in 2 days ;-)

Share this post


Link to post
Share on other sites

Oops, that's what we get for asking for more bug reports; the list of bugs doubled in 2 days ;-)

:-D I wouldn't have dared to hope that there are none left...

 

M-Network games seem to reset differently.

 

Example: Space Attack (1982) (Mattel).BIN

Older versions of Stella blank the screen to black while the reset key is held.

Pre-release 4 chops the top 1/4th of the screen off, makes the other 3/4th's flicker, and upon release of the reset key restores the image and makes it bounce 1 time. Don't know which the correct behavior or if this is important or not.

 

Seems different M-Network games behave differently when resetting them.

 

Maybe this is not a problem?

The new core comes with an algorithm to autodetect the first visible scanline. The effects you describe are a side effect. I've got a change in the pipeline that will remove most of thise.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...