Thanks TmEE co.(TM)!
Already done! Currently 15 colors are transferred per a scanline (with not substantial artifacts at the borders of the screen).
I hope it will be enough for my purposes.
Search found 158 matches
- Sun Nov 22, 2015 12:18 pm
- Forum: Megadrive/Genesis
- Topic: DMA transfer to CRAM visible however the screen is off.
- Replies: 28
- Views: 25883
- Sun Nov 22, 2015 7:52 am
- Forum: Megadrive/Genesis
- Topic: DMA transfer to CRAM visible however the screen is off.
- Replies: 28
- Views: 25883
Re: DMA transfer to CRAM visible however the screen is off.
I guessed that it was so but thanks a lot Mask of Destiny for the confirmation! I just hoped that there maybe would be any trick to overcome that. I wanted to turn off one per two scanlines and reload a full set of new 64 colors for each 2 scanlines but unfortunately there was too much CRAM artifact...
- Sun Nov 22, 2015 3:52 am
- Forum: Megadrive/Genesis
- Topic: DMA transfer to CRAM visible however the screen is off.
- Replies: 28
- Views: 25883
DMA transfer to CRAM visible however the screen is off.
I turn off the screen.
Then do a DMA transfer to CRAM.
And I see artifacts on the screen.
Why it happens? Is it possible to fix?
I thought if the screen is off then nothing must be visible.
Then do a DMA transfer to CRAM.
And I see artifacts on the screen.
Why it happens? Is it possible to fix?
I thought if the screen is off then nothing must be visible.
- Thu Nov 19, 2015 10:00 am
- Forum: Megadrive/Genesis
- Topic: Artifacts of the direct color DMA
- Replies: 4
- Views: 4417
Re: Artifacts of the direct color DMA
I know Stef but I hoped maybe there was a miracle (: It's very likely that it is impossible to turn off DRAM refresh. And if it would be possible very likely DRAM would lose its data and wouldn't be too much sense to do that. As far I know DRAM must refresh its content about that time that it's done...
- Thu Nov 19, 2015 6:48 am
- Forum: Megadrive/Genesis
- Topic: Artifacts of the direct color DMA
- Replies: 4
- Views: 4417
Artifacts of the direct color DMA
The direct color DMA has a drawback: 5 columns of doubled pixels.
As far I know the artifacts are caused by the need to refresh DRAM memory used in VDP's CRAM.
Does anyone know how to fix them?
Any suggestions are welcomed!
Thanks!
As far I know the artifacts are caused by the need to refresh DRAM memory used in VDP's CRAM.
Does anyone know how to fix them?
Any suggestions are welcomed!
Thanks!
- Tue Nov 17, 2015 3:13 pm
- Forum: Megadrive/Genesis
- Topic: More Interesting Code Snippets
- Replies: 1
- Views: 2795
Re: More Interesting Code Snippets
Sad there is not like-button as Facebook has.
I would use it with a pleasure.
LIKE VERY MUCH.
I would use it with a pleasure.
LIKE VERY MUCH.
- Thu Jul 23, 2015 2:20 pm
- Forum: Megadrive/Genesis
- Topic: Please help to fix the problem with screen on/off
- Replies: 3
- Views: 3231
You need to turn it back on at the correct time, so you should check for a specific H counter value before turning it ON again. Now I have another problem: how to make the synchronization stable? Few frames everything is excellent but some frame the screen shakes and then everything is ok. I only d...
- Wed Jul 22, 2015 5:59 pm
- Forum: Megadrive/Genesis
- Topic: Please help to fix the problem with screen on/off
- Replies: 3
- Views: 3231
- Wed Jul 22, 2015 3:04 pm
- Forum: Megadrive/Genesis
- Topic: Please help to fix the problem with screen on/off
- Replies: 3
- Views: 3231
Please help to fix the problem with screen on/off
Please help to fix the problem with screen on/off I am trying to turn off the screen in the first 16 lines of the screen in the top and the last 16 lines in the bottom to increase amount of data transferred in DMA with max speed. There are no problems in the top with it but in the bottom the black l...
- Sun Apr 05, 2015 6:46 am
- Forum: Blabla
- Topic: Revision 2015
- Replies: 3
- Views: 10163
- Thu Mar 12, 2015 2:11 pm
- Forum: Demos
- Topic: Please help to decide!
- Replies: 13
- Views: 8722
Steve Snake made the frist CRAM DMA demo. Actually, there are some words from a former Sega producer in Genesis Collective Works implying that the "blast processing" term was invented after seeing an internal demo using a DMA trick, which, done "at exactly the right time", let you "blast data onto ...
- Thu Mar 12, 2015 2:08 pm
- Forum: Demos
- Topic: Please help to decide!
- Replies: 13
- Views: 8722
You don't have to be sorry. I have a netbook and weak eyes, it doesn't help either :) I think I've seen the columns, but not sure (there's one that goes through the left structure ?) Interesting. How does it work eaxctly (a link is sufficient) ? And what causes the doubled columns ? Search this for...
- Thu Mar 12, 2015 4:02 am
- Forum: Megadrive/Genesis
- Topic: Help with compilation on Linux
- Replies: 3
- Views: 4002
For Linux I prefer this one: http://gendev.spritesmind.net/forum/viewtopic.php?t=889 And the sources of the library you can add from sgdk. Linux is more suitable for Sega development. I do it only on Linux but currently I am tied to some Windows software that works very bad in emulation on Linux and...
- Wed Mar 11, 2015 7:18 pm
- Forum: Demos
- Topic: Please help to decide!
- Replies: 13
- Views: 8722
I'm sorry but the video is very blurred. What am I supposed to see good and bad ? And what is this CRAM DMA trick ? Sorry for a phone camera. it is crabby. Even the blur of a phone camera cannot hide the artifacts. You should have seen them. 5 vertical columns of doubled pixels. The trick is called...
- Wed Mar 11, 2015 6:24 pm
- Forum: Demos
- Topic: Please help to decide!
- Replies: 13
- Views: 8722
thanks a lot guys for your help and participation! I think the same as Morden. It's ok for some fun but in my opinion unfortunately rather not suitable for a serious product than suitable. Very sad that Sega didn't make possibility to render RGB array directly to video output in a normal way. Howeve...