Search found 58 matches

by twosixonetwo
Wed Sep 10, 2014 9:52 am
Forum: Megadrive/Genesis
Topic: Emulator and TMSS
Replies: 13
Views: 3385

Are you sure your bios rom is working?
I tested the behaviour in Fusion with a bios rom and it worked like it should:

Original game:
Shows TMSS screen, then plays game.

Hacked rom without "SEGA" at 0x100:
Black screen

(Without the bios rom both versions ran)
by twosixonetwo
Wed Sep 10, 2014 8:57 am
Forum: Megadrive/Genesis
Topic: Emulator and TMSS
Replies: 13
Views: 3385

I'm not quite sure I understand what you want: Do you want it to hang, or to not hang? Either way, I am quite sure that TMSS is well researched so you should be safe by doing what toe segaretro article says if you want it NOT to hang on TMSS machines, or to make sure your rom does not comply with th...
by twosixonetwo
Sun Aug 31, 2014 1:40 pm
Forum: Sound
Topic: Complete beginner on sound programming
Replies: 4
Views: 2239

What tools would you recommend in making basic sine waves? The Mega Drive :D The Mega Drive gives zou access to two sound chips: The YM2612 and the PSG SN76489. The first gives you 6 voices (channels), so without further trickery you can play 6 notes on the YM2612 at the same time. The way these no...
by twosixonetwo
Sat Aug 30, 2014 6:11 pm
Forum: Sound
Topic: Complete beginner on sound programming
Replies: 4
Views: 2239

Can you name some specific things that made you trouble understanding? I guess recreating sounds with FM synthesis is one of the most unintuitive thing in sound programming for the mega drive, but for your first tests you could limit yourself to basic sine-waves. Also sample output is not so easy to...
by twosixonetwo
Tue Aug 26, 2014 8:43 am
Forum: Demos
Topic: Rom dumping over audio
Replies: 5
Views: 1993

I think this might work on the Sega CD (so you wouldn't need a flash cartridge). Insert cartridge after Sega CD is running from RAM, would also need to use the modify the catridge address since different starting address with the Sega CD in use, and if you are already using the 68k for the audio po...
by twosixonetwo
Mon Aug 25, 2014 7:50 am
Forum: Demos
Topic: Rom dumping over audio
Replies: 5
Views: 1993

Rom dumping over audio

Let me begin by stating that this is isn't a finished product and I wouldn't advice anyone to use this in its current state to create a backup archive of their games. What I want to show here is a mess that I hacked together until it finally worked. Link to the files What is it? It's a method to dum...
by twosixonetwo
Sun Aug 10, 2014 11:12 am
Forum: Megadrive/Genesis
Topic: Cycle counting on real hardware
Replies: 8
Views: 2235

Could you post the code for cases 3,4 and 8? Test 3/7: |Test 3 move.l #7000, %d0 move.b #0x00,0xA04001 | set TL countCycles_l5: move.l 0x000000, %d1 sub.l #1, %d0 bne countCycles_l5 move.b #0x7F,0xA04001 | set TL Test 4/8: |Test 4 move.l #7000, %d0 move.b #0x00,0xA04001 | set TL countCycles_l7: mov...
by twosixonetwo
Sat Aug 09, 2014 7:20 am
Forum: SGDK
Topic: Sega Genesis Dev Kit (SGDK)
Replies: 773
Views: 328083

IIRC the transparent color on the mega drive is always the first in the palette. Try reordering the colors in the bitmap and it might solve that issue.
by twosixonetwo
Fri Aug 08, 2014 11:36 am
Forum: Megadrive/Genesis
Topic: Cycle counting on real hardware
Replies: 8
Views: 2235

Okay, so refresh cycles might very well be the reason why the code execution from ram is slower than from rom. However is the Z80 stealing cycles even when it does nothing? I don't transfer anything to the Z80, and Exodus doesn't show any execution there (it doesn't run through the NOPs so it should...
by twosixonetwo
Thu Aug 07, 2014 3:45 pm
Forum: Megadrive/Genesis
Topic: Cycle counting on real hardware
Replies: 8
Views: 2235

Cycle counting on real hardware

So I have been running some tests because I had concerns that my code ran in the time it should on real hardware and timed some loops. To time my loops i made a sinewave, which I recorded with 96000 hz samplerate. So I basically set the volume to max, run my loop, and set the volume to min again: mo...
by twosixonetwo
Wed Aug 06, 2014 10:21 am
Forum: SGDK
Topic: Strange compiler errors [solved]
Replies: 8
Views: 1741

Case closed. Updated sgdk from 0.95 to 0.96d and the strange errors went away. Sorry for the confusion caused. :oops:
by twosixonetwo
Mon Aug 04, 2014 11:35 am
Forum: SGDK
Topic: Strange compiler errors [solved]
Replies: 8
Views: 1741

Ahh... well now I realize what your change meant. I have never written a makefile from scratch and wasn't really aware of how the change was supposed to work. So, I now use the newest makefile ( https://code.google.com/p/sgdk/source/browse/trunk/makefile.gen?spec=svn194&r=194 ) and the strange compi...
by twosixonetwo
Mon Aug 04, 2014 11:24 am
Forum: Blabla
Topic: Forum rules regarding rom dumping topics
Replies: 1
Views: 1785

Forum rules regarding rom dumping topics

I am currently developing a method with which one can dump roms without the need of an extra rom-dumping device. I thought this might be of interest to some of the users here but as the subtitle for the hardware forum says "For hardware talk only (please avoid ROM dumper stuff)". I don't think that ...
by twosixonetwo
Sat Aug 02, 2014 7:25 pm
Forum: SGDK
Topic: Strange compiler errors [solved]
Replies: 8
Views: 1741

Yes, that's unnecessary, doesn't create any problems though. (IIRC) it's merely an empty statement.
I removed it and the strange compiler message remains...
by twosixonetwo
Sat Aug 02, 2014 12:50 pm
Forum: SGDK
Topic: Strange compiler errors [solved]
Replies: 8
Views: 1741

Well, the newest makefile doesn't work for me since I've got the sega.s and the rom_head.c in my src folder: C:\sgdk\projects\SVPDemo>%GDK_WIN%\bin\make -f makefile.gen make: *** No rule to make target `C:/sgdk/src/boot/sega.s', needed by `src/boot/sega.s'. Stop. If I change $(SRC)/boot/sega.s: $(LI...