Search found 82 matches
- Tue Dec 27, 2016 7:05 pm
- Forum: Megadrive/Genesis
- Topic: XBAND, Mega Net 2, and Mega Drive Keyboards
- Replies: 20
- Views: 15424
XBAND, Mega Net 2, and Mega Drive Keyboards
Hello, we are doing some research, and investigating if it would be possible to be able to acquire a keyboard and a ROM to verify it works, write few test ROMs and documentation, and in the end get it emulated on emulators that are currently being worked on (GPGX comes to mind first). The cool thing...
- Wed Dec 21, 2016 12:03 pm
- Forum: SGDK
- Topic: about sprites
- Replies: 16
- Views: 9848
Re: about sprites
if you use 32x8 sprites, its enough to just fill the entire 320px. I tried to do a fancy sprite scroller, and it would need exactly 1 more sprite being displayed (so you can't see the edges), but VDP could not handle it, so I instead had to do hacks with planew+planea to display both FG and the scro...
- Sat Nov 12, 2016 5:42 pm
- Forum: Megadrive/Genesis
- Topic: Fastest way to clear memory
- Replies: 8
- Views: 5774
Re: Fastest way to clear memory
Having the clear a huge chunk of memory each frame is terrible design, and you need to redesign your system to not require that. Otherwise what you are doing is not feasible
- Fri Nov 04, 2016 2:01 am
- Forum: Video Display Processor
- Topic: DMA failure on different consoles.
- Replies: 12
- Views: 13595
Re: DMA failure on different consoles.
Now, this may be completely crazy suggestion, but try clearing the RAM after init but before any other DMA. Don't bother making it efficient, you just want to waste time. This fixed major issues with a homebrew I wrote earlier. Without this, the graphics wouldn't look right, or just nothing loaded. ...
- Tue Nov 01, 2016 2:46 pm
- Forum: Video Display Processor
- Topic: DMA failure on different consoles.
- Replies: 12
- Views: 13595
Re: DMA failure on different consoles.
Sanity check; disable ints. Always disable ints when writing to VDP unless you can be sure there is no possibility of ints happening (like during VInt with no HInts). Or better yet, write better DMA code. This one here is terribly slow, and increases likelihood of ints happening during it. The best ...
- Thu Oct 27, 2016 8:00 pm
- Forum: Video Display Processor
- Topic: VDP Tools ? (calc)
- Replies: 4
- Views: 8581
Re: VDP Tools ? (calc)
Yes it is a mess, but it is also very versatile. You can replicate any possible combination of instructions and modifiers to do anything you like. You could do that or.w #$4000,d0 with the macro too, and make it "easier to edit"
- Thu Oct 27, 2016 2:23 pm
- Forum: Video Display Processor
- Topic: VDP Tools ? (calc)
- Replies: 4
- Views: 8581
Re: VDP Tools ? (calc)
A lot of the time I use this bot called DocScratch (also ChaosGamma) on irc.badnik.zone that has a !vdp command, to convert from and to VDP commands. I also have the following macros for laziness' sake; vdpComm macro ins,addr,type,rwd,end,end2 if narg=5 \ins #(((\type&\rwd)&3)<<30)|(((\addr)&$3FFF)<...
- Wed Oct 26, 2016 9:02 pm
- Forum: Demos
- Topic: Totino Challenge
- Replies: 1
- Views: 3415
Totino Challenge
So, since the topic for RAGE this year was Totinos , I present to you Totino Challenge! A quick homebrew I wrote in 24 hours for the contest. Even with the bad topic, I decided to take it on for the challenge. I think it turned out very well for the little time I had to write it in. In fact, I have ...
- Fri Sep 09, 2016 8:06 pm
- Forum: Megadrive/Genesis
- Topic: How to build a self-running demo?
- Replies: 11
- Views: 6894
Re: How to build a self-running demo?
Sik; You could also emulate pressed/held states on demo code you know
- Thu Sep 08, 2016 11:19 am
- Forum: Megadrive/Genesis
- Topic: How to build a self-running demo?
- Replies: 11
- Views: 6894
Re: How to build a self-running demo?
To be more specific, Sonic 1 has duplicate vaöues for button presses; one for players (Sonic), and one for controller (Ctrl 1). During demo, instead of reading input from ctrl 1 for Sonic, it reads from ROM. Start button is checked from ctrl 1 so it will still work (and by extension a demo cannot en...
- Wed Sep 07, 2016 5:48 am
- Forum: Megadrive/Genesis
- Topic: How to build a self-running demo?
- Replies: 11
- Views: 6894
Re: How to build a self-running demo?
oftentimes games would just override the controller input with data from a file. Games need to be programmed with this in mind, however, so the game correctly responds to held/pressed states and keeps in sync! The way Sonic 1 is precisely this, and the buttons are (thought to) be recorded via unused...
- Tue Aug 30, 2016 6:11 am
- Forum: Video Display Processor
- Topic: VDP access from Z80 questions
- Replies: 16
- Views: 19418
Re: VDP access from Z80 questions
Ive never had timing issues on v-int. Even with a lot of DMA's happening durint it, h-ints start at line 0. You should invest in fast and clean code durint v-int either way, or it could take a lot of unnecessary CPU time
- Sun Aug 28, 2016 5:23 pm
- Forum: Video Display Processor
- Topic: VDP access from Z80 questions
- Replies: 16
- Views: 19418
Re: VDP access from Z80 questions
Whenever I do anything on h-int each line, I load the code in RAM, then do this: move.l #vdpcommand,$C00004 HintAddr = *+2 move.w addr.w,$C00000 addq.w #2,HintAddr.w rte This is a very quick way to issue VDP commands and write to VRAM, CRAM, and VSRAM. As a bonus it uses no registers and uses only 2...
- Fri Aug 12, 2016 9:31 am
- Forum: Megadrive/Genesis
- Topic: Mega Everdrive USB programming
- Replies: 6
- Views: 6353
Re: Mega Everdrive USB programming
Ive done a server/client test sometime back. Although its hacky I can share some of the code if you wish. Server is written in C# and client in ASM. I used this to test streaming music files, but the connection is too slow or unreliable to work properly.
- Fri Aug 12, 2016 9:29 am
- Forum: Announcement
- Topic: Idea to help slow down spammers
- Replies: 8
- Views: 12759
Re: Idea to help slow down spammers
You probably could just use S3K's maze generation algorithm to figure out this problem. The good side is that just any non-Sonic geek or someone who doesnt understand 68000 wouldnt be able to so easily get this thing working.