Search found 102 matches

by Alyosha_TAS
Sun Nov 18, 2018 8:21 am
Forum: GBDev
Topic: Telling LYs? (test ROM)
Replies: 11
Views: 14010

Re: Telling LYs? (test ROM)

Ha! That's clever. I like trickery like this.
by Alyosha_TAS
Sat Oct 13, 2018 7:17 am
Forum: GBDev
Topic: GB Emulator - Issues with cpu_instrs
Replies: 1
Views: 6473

Re: GB Emulator - Issues with cpu_instrs

I find the fastest way to do this is to log all executing instructions to a text file and then just compare against a log from a working emulator. If your emulator can't already do this I strongly suggest it as it has saved me countless hours.
by Alyosha_TAS
Sat Oct 06, 2018 6:36 am
Forum: GBDev
Topic: GBC Compatibility Register
Replies: 1
Views: 5070

GBC Compatibility Register

Hi, I am wondering if anyone has any information on the register at $FF4C. This seems to be the location where the game compatibility information at $0143 is written to from the game ROM. Does anyone know what this is doing? I am particularly curious if this has any effect on test ROMs which run wit...
by Alyosha_TAS
Mon Apr 02, 2018 7:22 pm
Forum: GBDev
Topic: GBC Warriors of Might and Magic
Replies: 2
Views: 4346

Re: GBC Warriors of Might and Magic

Cool, thank you for testing tobiasvl!

I would have bet that the complete border would have been correct but hardware wins. I would think the border was intended based on how it’s stored in the window, I wonder what went wrong ?
by Alyosha_TAS
Thu Mar 29, 2018 6:47 am
Forum: GBDev
Topic: GBC Warriors of Might and Magic
Replies: 2
Views: 4346

GBC Warriors of Might and Magic

Hi all, I have a question regarding this game and am wondering if anyone has this game on console to do a quick test. In pictures I see online and in Gambatte, the screen looks like this: https://image.ibb.co/mPeMs7/mm_gam.png Notice that at the split between the playfield and the status bar, ex 'HP...
by Alyosha_TAS
Fri Jan 19, 2018 8:23 am
Forum: GBDev
Topic: Passing Gekkio's intr_2_mode0_timing_sprites test ROM
Replies: 1
Views: 3223

Passing Gekkio's intr_2_mode0_timing_sprites test ROM

Hi All, I recently managed to pass Gekkio's sprite timing test rom in my emulator. This test seemed pretty intimidating at first, but it turned out that a fairly simple algorithm can be used to correctly account for the ppu cycles that are used to evaluate the sprites. I thought I would share this h...
by Alyosha_TAS
Tue Dec 19, 2017 12:55 pm
Forum: GBDev
Topic: [Homebrew] My first game... yet another Snake!
Replies: 20
Views: 14592

Re: [Homebrew] My first game... yet another Snake!

New version... Not much did change, but I added a cherry, which gives 5 points. Also, I did put in the animations. As it turned out, the game goes too fast for them to be any good :shock: (specially on my ultra-blurry gbpocket :lol: ), but the one with the eating head also appears when you eat your...
by Alyosha_TAS
Fri Dec 08, 2017 8:11 am
Forum: GBDev
Topic: [Homebrew] My first game... yet another Snake!
Replies: 20
Views: 14592

Re: [Homebrew] My first game... yet another Snake!

much more fun to play now with the softer toned music.

I think it could us some more animations though, like one for eating the egg, or the snakes belly segments expeanding as he swallows it.
by Alyosha_TAS
Wed Dec 06, 2017 8:45 am
Forum: GBDev
Topic: Naughtyemu, what is it doing? [solved]
Replies: 4
Views: 2795

Re: Naughtyemu, what is it doing?

Ahhh ok that makes sense. So the fundamental behaviour I was missing was the OAM DMA is halted when the CPU is halted, got it. The bus conflict this causes makes OAM unreadable/glitchy mess to the ppu when it's processing sprites. Cool, implementing that was enough to get the blank screen in naughty...
by Alyosha_TAS
Wed Dec 06, 2017 6:16 am
Forum: GBDev
Topic: Naughtyemu, what is it doing? [solved]
Replies: 4
Views: 2795

Re: Naughtyemu, what is it doing?

I can post further details and the source if you're interested :) However, I have to warn that emulating the behaviour correctly right now is probably not possible because we don't understand it well enough. IIRC the behaviour wasn't even the same on all models...I think even MGB and DMG were diffe...
by Alyosha_TAS
Tue Dec 05, 2017 6:45 pm
Forum: GBDev
Topic: Naughtyemu, what is it doing? [solved]
Replies: 4
Views: 2795

Naughtyemu, what is it doing? [solved]

I see this ROM as part of Gekkio's files, but I can't seem to find a lot of information about it. So far every emulator I test it on prints the message "Naughty emulator! No presents for you!" I'm guessing that means it's a failure. It looks like the what it's doing is using the timer and some midfr...
by Alyosha_TAS
Mon Dec 04, 2017 12:36 pm
Forum: GBDev
Topic: Prehistorik Man intro music [solved]
Replies: 6
Views: 3281

Re: Prehistorik Man intro music

I had the exact same problem with my emulator. It is fixed via the effects described in the 'obscure behaviour' section here: "Zombie" mode: the volume can be manually altered while a channel is playing by writing to NRx2. Behavior depends on the old and new values of NRx2, and whether the envlope h...
by Alyosha_TAS
Mon Dec 04, 2017 7:37 am
Forum: GBDev
Topic: [Homebrew] My first game... yet another Snake!
Replies: 20
Views: 14592

Re: [Homebrew] My first game... yet another Snake!

The nintendo logo scrolling off the bottom of the screen was a clever touch :) When the snake goes off the top of the screen the last tail section glitches out. It looks like it's getting flipped before scrolling off. I also agree that the music is a bit harsh sounding. Impressive for only a couple ...
by Alyosha_TAS
Sun Dec 03, 2017 4:47 pm
Forum: GBDev
Topic: Kirby's Dreamland, broken Startup Screen [solved]
Replies: 3
Views: 2286

Re: Kirby's Dreamland, broken Startup Screen

That screen is from before the intro screen. It pops up a few frames after the boot rom is complete (frame 333 on my emulator.) Gambatte also has SY getting set to 8 at this time, in 2 seperate places: 018E: 3E 08 LD A,#08h A:e4 B:00 C:00 D:de E:42 F:80 H:ff L:23 LY:91 SP:fffe Cy:531140 0190: E0 42 ...
by Alyosha_TAS
Sun Dec 03, 2017 1:46 pm
Forum: GBDev
Topic: Kirby's Dreamland, broken Startup Screen [solved]
Replies: 3
Views: 2286

Kirby's Dreamland, broken Startup Screen [solved]

Hi all, I've got another graphical glitch that I can't seem to find the resolution to. On Kirby's Dreamland, for one frame while loading, before the main intro draws, I get this screen: https://image.ibb.co/jaxQfG/kirby_glitch.png Here are the states of relevent registers when the drawing occurs: LC...