Search found 52 matches

by Orion_
Mon May 13, 2013 5:14 pm
Forum: Blabla
Topic: PS1 Homebrew Development
Replies: 10
Views: 11606

I have been coding my library for the Playstation since 2004, how old is your psxsdk open source project ? Plus, I didn't have enough low level knowledge of the Playstation back then, and understanding the PsyQ sdk was already hard for me. There is a lots of stuff I can't do with your sdk and that I...
by Orion_
Sun May 12, 2013 8:34 am
Forum: Blabla
Topic: PS1 Homebrew Development
Replies: 10
Views: 11606

If you get the official sony sdk, you can do everything for the psx, there are C library for that. I really love the psx and the genesis, but it seems that the homebrew community is way bigger for the genesis. I think the psx is much more powerful once you get how the system works (and if you are no...
by Orion_
Wed May 08, 2013 12:32 pm
Forum: Demos
Topic: Direct Color Demo using DMA
Replies: 91
Views: 122407

I tried to do some simulation with Direct Color DMA mode, but I get better result with 4 palettes tile mode. Direct DMA RGB:333 160x224 -> 320x224 simulation http://onorisoft.free.fr/extern/titledma.png Tile mode 4 palettes RGB:333 320x224 (Fusion emu screenshot) http://onorisoft.free.fr/extern/titl...
by Orion_
Wed May 08, 2013 8:42 am
Forum: Video Display Processor
Topic: Freeze the screen while updating the VRAM
Replies: 8
Views: 7387

For my first test I used the everdrive sdk which seems based on sgdk, but I have the sgdk too :) I think I got it :) NTSC 262 lines total PAL 312 lines total 224 lines of active display dma speed during vblank 205 bytes per line NTSC vblank total (262-224)*205=7790 PAL vblank total (312-224)*205=180...
by Orion_
Tue May 07, 2013 5:27 pm
Forum: Video Display Processor
Topic: Freeze the screen while updating the VRAM
Replies: 8
Views: 7387

Thanks for the details, so, I understand now, if it can only transfer 18 bytes per line during active display, while holding the 68k, it's not really useful. I thought you could transfer at fullspeed during active display, so transferring a complete screen for example.. but It's just logical, the vr...
by Orion_
Tue May 07, 2013 2:53 pm
Forum: Video Display Processor
Topic: Freeze the screen while updating the VRAM
Replies: 8
Views: 7387

Hello, This is something I'm curious about, I'm just starting genesis coding, and didn't tried DMA yet, but I always read on tech docs and forum that DMA can only transfer 7kb of datas during vblank. What's happening if we transfer data during screen rendering ? Does this make glitch appearing on sc...
by Orion_
Mon May 02, 2011 2:36 pm
Forum: Mega/SegaCD
Topic: Mega Drive to Mega CD?
Replies: 29
Views: 33343

lukeusher123 > I was searching info on sega cd dev, and couldn't find a lot's of infos apart retrodev.com sources, and then I saw your dev kit, very understandable with lots of comments and working perfect, thanks a lot for your work on this !