Search found 321 matches

by Shonumi
Sat Dec 02, 2017 5:29 pm
Forum: GBDev
Topic: GBC Marble Madness window position [solved]
Replies: 9
Views: 3686

Re: GBC Marble Madness window position

Does this mean that the window is always drawn row-by-row from top-to-bottom? Or, is there a way to actually hide or skip over a set of rows? Yes, the window appears to be line-by-line, top-to-bottom. I don't think it's possible to skip lines; you can only delay rendering them for a given frame. Wh...
by Shonumi
Sat Dec 02, 2017 1:28 pm
Forum: GBDev
Topic: GBC Marble Madness window position [solved]
Replies: 9
Views: 3686

Re: GBC Marble Madness window position

Alright, here's the test ROM you can use, along with a screen shot of the expected output. Top part is just standard BG rendering (WX = 0xA7), but the bottom part is the actual Window. It starts rendering by setting WX to 0x7, then sets it to 0xA7 a little later, then sets it back to 0x7 to resume r...
by Shonumi
Fri Dec 01, 2017 3:26 pm
Forum: GBDev
Topic: GBC Marble Madness window position [solved]
Replies: 9
Views: 3686

Re: GBC Marble Madness window position

I think I found a clue . The behavior in Marble Madness is the same as Star Trek: The 25th Anniversary in terms of Window graphics. The difference is that where Star Trek disables and re-enables the Window via the LCDC register, Marble Madness disables and re-enables the Window via WX. The end resu...
by Shonumi
Sun Nov 26, 2017 10:43 am
Forum: GBDev
Topic: Beast Fighter and Window Function, does it work on hardware?
Replies: 11
Views: 4415

Re: Beast Fighter and Window Function, does it work on hardw

Fwiw, I'm just assuming values of 1-6 of WX get translated to 0. I never got around to making a test ROM myself. I believe that garbage data is supposed to be drawn to the screen, but the window in SW EP1 - Racer is all black, so even when it ends up pulling "random" values, the BG/WIN data in VRAM ...
by Shonumi
Sun Nov 26, 2017 10:25 am
Forum: GBDev
Topic: Beast Fighter and Window Function, does it work on hardware?
Replies: 11
Views: 4415

Re: Beast Fighter and Window Function, does it work on hardw

If the WX, WY and window on flag conditions are all true at the same time, the PPU goes into window rendering mode. It then draws the window on each following line, starting at X position specified by WX, and the line counter is incremented for each consecutive line. (What I'm calling the line coun...
by Shonumi
Sat Sep 09, 2017 7:04 pm
Forum: GBDev
Topic: My EverDrive arrived. Now what GBC emulator in 2017?
Replies: 9
Views: 5852

Re: My EverDrive arrived. Now what GBC emulator in 2017?

AFAIK, the only open source DMG/GBC emulators that, in part, focus on debugging tools (especially GUI ones) are endrift's mGBA and my own GBE+. If you're looking for CLI debugging stuff, GBE+ is pretty advanced. I've been holding off on improving the debugging GUI (and expanding it to GBA stuff) unt...
by Shonumi
Wed Sep 06, 2017 6:50 am
Forum: GBDev
Topic: Can someone test games on real GB hardware?
Replies: 13
Views: 4922

Re: Can someone test games on real GB hardware?

If you're going to be writing your own tests, having (close to) 100% compatibility isn't really an issue. That is to say, if you want to do your own low-level tests of hardware behavior (the actual Game Boy, not the MBC itself) you often don't need anything much fancier than 32KB of ROM and maybe th...
by Shonumi
Tue Sep 05, 2017 6:50 pm
Forum: GBDev
Topic: Can someone test games on real GB hardware?
Replies: 13
Views: 4922

Re: Can someone test games on real GB hardware?

For the cart flasher, I got mine from BennVenn. He's based in Australia if I recall correctly, so for you it's international shipping regardless. There's this flasher from someone based in Spain, so that might be more favorable to you. Unfortunately, both BennVenn's and JRodrigo's flashers are sold ...
by Shonumi
Mon Sep 04, 2017 12:00 pm
Forum: GBDev
Topic: When it LY/LYC Coincidence checked?
Replies: 10
Views: 4685

Re: When it LY/LYC Coincidence checked?

Confused when you say you can put a ROM on the flashcart, and later you say if you don't have a flashcart reader you need to print visual statuses. How would i even get the ROM to the flashcart without a flashcart reader, isn't that what you use to R/W to it;o? Well, for me, I use Linux. There are ...
by Shonumi
Mon Sep 04, 2017 7:49 am
Forum: GBDev
Topic: When it LY/LYC Coincidence checked?
Replies: 10
Views: 4685

Re: When it LY/LYC Coincidence checked?

Btw why would i want several GameBoys, one expects them to break? You'll need at least two if you want to do hardware tests on multiplayer stuff (standard 2-player stuff e.g. Pokemon battles/trading). It's not necessary, but yes, having a backup is always a good idea. Game Boys are pretty durable a...
by Shonumi
Sun Sep 03, 2017 1:10 pm
Forum: GBDev
Topic: Game Boy display disable/enable and frame timing
Replies: 6
Views: 4422

Re: Game Boy display disable/enable and frame timing

In that case it LY also reset, cause otherwise it would go out of sync with that clock right? Already mentioned it here but yes, LY gets reset to 0 when the LCD is disabled. Otherwise weird things would happen. And also, when it's disabled, is the clock stopped, or does it run and it just resets wh...
by Shonumi
Sun Sep 03, 2017 12:25 pm
Forum: GBDev
Topic: When it LY/LYC Coincidence checked?
Replies: 10
Views: 4685

Re: When it LY/LYC Coincidence checked?

GB documentation is a mess. Stuff is scattered all over the place in different resources. And on top of that, we're still learning new things even today. Just look at gekkio, endrift, or LIJI32's work. I've been tackling lots of crazy accessories as well (Barcode Taisen Bargidun, the Barcode Boy, th...
by Shonumi
Sun Sep 03, 2017 9:22 am
Forum: GBDev
Topic: When it LY/LYC Coincidence checked?
Replies: 10
Views: 4685

Re: When it LY/LYC Coincidence checked?

Ah, but what if you write to LY so it resets? I think this is another famous example of how poor Game Boy documentation can be. That bit of info is from Pan Docs, which is incorrect. Any writes to LY while the LCD is enabled are ignored. When the LCD is disabled, LY is forcibly set to 0, and since ...
by Shonumi
Sat Sep 02, 2017 4:28 pm
Forum: GBDev
Topic: When it LY/LYC Coincidence checked?
Replies: 10
Views: 4685

Re: When it LY/LYC Coincidence checked?

but what happens when the actual flag to check is set, does a check occur at that moment, or will it wait till the next LY increment? When you write a new value to LYC, this forces an immediate comparison between LY and LYC. You can use this to manually fire a STAT interrupt via LYC. The game Sagai...
by Shonumi
Tue Aug 01, 2017 8:47 am
Forum: GBDev
Topic: Game Boy Color bug - Oracle of Ages transitions [fixed]
Replies: 14
Views: 5082

Re: Game Boy Color bug - Oracle of Ages transitions [fixed]

So to be clear, the entire time the LCD is warminig up again, LY is read back as zero, yes? Not sure. Maybe someone else knows. If you turn it on, I'm assuming that it functionally "works" in the sense that interrupts and DMAs and anything related to the LCD starts up again, just that the LCD won't...