Search found 255 matches

by TascoDLX
Thu Oct 02, 2014 2:45 am
Forum: Mega/SegaCD
Topic: Disassembling the Digital Pictures media codec
Replies: 15
Views: 7122

I totally missed this post. :oops: I don't think it would be too hard, but I never really had any desire to reverse engineer the player. It depends on how much experience you have doing that and how thorough you want to be about it. I don't know how much progress you've made, but I'll take a look at...
by TascoDLX
Thu Oct 02, 2014 1:56 am
Forum: Megadrive/Genesis
Topic: TMSS help.
Replies: 26
Views: 5203

Thanks for the useful information friend. I corrected the issues you mentioned, and now after reading some of those posts have a feeling there will be more even once this gets running on real hardware. Well... here goes nothing. https://www.mediafire.com/?l8dsi6pyiosyeqh You slightly missed the poi...
by TascoDLX
Wed Oct 01, 2014 4:17 am
Forum: Megadrive/Genesis
Topic: TMSS help.
Replies: 26
Views: 5203

Take a look at your VDP regs initialization. It's probably not a good thing that you're enabling DMA for no reason. Regardless of that, you can crash some systems by writing the DMA regs and NOT triggering DMA. If you really want to init the DMA regs (and you probably shouldn't touch them unless you...
by TascoDLX
Thu May 01, 2014 7:51 am
Forum: Mega/SegaCD
Topic: Reading subcode data on the MegaCD
Replies: 12
Views: 5891

There's no documentation on exactly when you should call the CDCSETMODE routine. I found the only time I could get it to do anything useful was if I called it for each sector, after CDCSTAT reported that a sector was available. Not to quote myself, but... "Calling CDCSETMODE doesn't change the CDC ...
by TascoDLX
Wed Apr 30, 2014 4:04 am
Forum: Mega/SegaCD
Topic: Reading subcode data on the MegaCD
Replies: 12
Views: 5891

I only skimmed your post. I'll come back to it, but this part... I also basically don't understand the way the BIOS reads, buffers, and sends sector data to my code, which doesn't help matters. What do CDCSTAT, CDCREAD, and CDCTRN actually do, in a nutshell, and where is the actual data at each stag...
by TascoDLX
Thu Feb 06, 2014 2:04 pm
Forum: Blabla
Topic: sega.doc legal issues
Replies: 2
Views: 2265

At best, the publication of so-called "confidential" information is a matter of trade secret law. The fact that the information has been public for so long (not to mention it concerns ancient hardware) effectively voids the confidentiality status and nullifies any claim to trade secret. Copyright la...
by TascoDLX
Wed Jan 08, 2014 6:25 am
Forum: Mega/SegaCD
Topic: Reading subcode data on the MegaCD
Replies: 12
Views: 5891

I finally managed to get something out of the hardware last night while testing this stuff, but I had limited time to work on it, so I wasn't able to verify my results, but still, I managed to initialize subcode reading and get something out of the SCDREAD and SCDPQ functions. I'm still not quite s...
by TascoDLX
Tue Jan 07, 2014 1:25 pm
Forum: Mega/SegaCD
Topic: Reading subcode data on the MegaCD
Replies: 12
Views: 5891

Re: Reading subcode data on the MegaCD

Well, the BIOS uses the subcode functions for CD+G. In fact, the R-W data delivered by the subcode functions is actually deinterleaved CD+G data, though that's not mentioned in the docs. If you want the full subcode data, you have to read it out yourself from the gate array buffer during the SCD-INT...
by TascoDLX
Mon Jan 06, 2014 4:12 am
Forum: Mega/SegaCD
Topic: Booting CD from Cart ?
Replies: 36
Views: 10372

Code: Select all

   move.l   $416000,a0
   lea   $420000,a1
   bsr   Kos_Decomp
Bad move. ;)
by TascoDLX
Sat Jan 04, 2014 1:04 pm
Forum: Mega/SegaCD
Topic: Testing boot from CARTRIDGE SLOT at 0x400000
Replies: 14
Views: 5947

This should give you a quick insight of where the boot check code is on each bios. After this detection is done, the next thing the BIOS do at that region is attempt detection "RAM_CARTRIDG" string at $400010. All CD BIOSes seem to do this regardless of region. Ah yes, I think I remember RAM_CARTRI...
by TascoDLX
Thu Nov 21, 2013 12:45 pm
Forum: Super 32X
Topic: Night Trap 32X video compression
Replies: 17
Views: 8393

Congrats! Source code release would be cool, I'd check that out. I might even look into decoding other SGA vid packets. Never really looked beyond Night Trap & Sewer Shark.
by TascoDLX
Wed Nov 20, 2013 2:40 am
Forum: Exodus
Topic: Problem with input
Replies: 6
Views: 2769

It's not very obvious, but you need to have the "Image" window selected right now in order for input to be captured. Just clicking on the menu will cause you to lose focus on the Image window, and input will no longer be captured by the emulator. I'd guess that's what's causing your problem. There ...
by TascoDLX
Fri Nov 15, 2013 5:53 am
Forum: Super 32X
Topic: Night Trap 32X video compression
Replies: 17
Views: 8393

Super cool! Thanks! I can't believe we (mostly you) were able cracked the code so quickly. No problem. To be fair, it could have been a lot more complicated if they decided to do more than just boost the colors of the Sega CD version. Luckily they settled for a relatively simple format, so it was p...
by TascoDLX
Wed Nov 13, 2013 6:46 am
Forum: Super 32X
Topic: Night Trap 32X video compression
Replies: 17
Views: 8393

Files: Night Trap 32X Video Codebook - 2013.11.12.txt NT32XVID-FIXED-OPS.PNG Opcode listing is at the end of the text doc -- pretty much all verified. PNG contains all the 2-color fixed patterns, some of which can be referred to by multiple opcodes (don't know how much of that is intentional). The c...
by TascoDLX
Tue Nov 12, 2013 7:08 am
Forum: Super 32X
Topic: Night Trap 32X video compression
Replies: 17
Views: 8393

This is great! I hope you're having fun working on this. I know my curiosity is piqued. :-) I suppose we could figure out all of the codes by disassembling the game code and finding the right routines, but it might actually be more interesting ths way. Oh definitely, this is very interesting. A lot...