Search found 188 matches

by Huge
Mon Apr 15, 2019 1:33 am
Forum: Megadrive/Genesis
Topic: Compiling an emulator for enhanced Megadrive
Replies: 42
Views: 767

Re: Compiling an emulator for enhanced Megadrive

There's little point to the "Tower of power" when a Saturn is better for all practical purposes. Still being a Genesis is part of the constraint. How about going backwards then: making something for the Saturn to run Megadrive games ? Obviously doing it in software alone would be near insanity, but...
by Huge
Tue Apr 09, 2019 7:55 pm
Forum: Megadrive/Genesis
Topic: Compiling an emulator for enhanced Megadrive
Replies: 42
Views: 767

Re: Compiling an emulator for enhanced Megadrive

How does the C2 have 15bit colour? I thought it just had the external palette hooked up to double the entries from four to eight.
by Huge
Tue Mar 26, 2019 1:54 pm
Forum: Megadrive/Genesis
Topic: Space Herrier II and The Sprite Scanline Limit
Replies: 11
Views: 538

Re: Space Herrier II and The Sprite Scanline Limit

Keio Flying Squadron does something like that, using sprites as a background. At one point (around stage 5 or 6?) it has a huge Ark that splashes onto the sea and you have to catch up with it. Normally the sea takes up all the backgrounds, and once you reach the ark, it's made up of sprites only. Th...
by Huge
Sun Oct 28, 2018 9:35 pm
Forum: MegaLD
Topic: MegaLD Dumping Project
Replies: 73
Views: 32401

Re: MegaLD Dumping Project

by Huge
Tue Sep 18, 2018 12:33 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

Yeah, 14.318 / 4 = 3.579545 MHz and 17.734 / 4 = 4.43361875 MHz, the NTSC and PAL colour bursts, respectively. The PLL outputs them to the video encoder.
by Huge
Mon Sep 17, 2018 10:05 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

Thanks for this complete answer ! So it could be possible to overclock the saturn but not without affecting video signal? No, the VDP2 generates the dot clock using the input clock / 4. If you over or underclock the system, it will display the wrong resolution and/or the wrong h/v sync and the imag...
by Huge
Mon Sep 17, 2018 1:04 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

The SH2/VDP1/VDP2/SCU clocks are generated by a PLL (IC20), which uses 14.318MHz * 2 = 28.6 MHz in 352px mode. In 320px mode, it runs the frequency through a 1708/1820 divider to get 26.8MHz. SCU DSP runs at half of that. In PAL units it uses a 17,734 MHz crystal and it is run through a 910/1135 div...
by Huge
Mon Sep 03, 2018 10:10 pm
Forum: Exodus
Topic: Exodus 2.1 release soon (Now available!)
Replies: 40
Views: 5478

Re: Exodus 2.1 release soon

awye wrote:
Mon Sep 03, 2018 9:23 am
Nemesis wrote:
Wed Aug 29, 2018 12:09 am
So, anything else? :)
Master System support possible? :roll:
This is actually a good question, since the Megadrive VDP has almost all the SMS functions, and Exodus is supposed to emulate the VDP perfectly.
by Huge
Fri Aug 31, 2018 2:56 am
Forum: Exodus
Topic: Exodus 2.1 release soon (Now available!)
Replies: 40
Views: 5478

Re: Exodus 2.1 release soon (Now available!)

If I may say, it is great to have you back developing stuff. The projects you are handling are all truly one of a kind in how advanced they are, and it is great to see them progressing even if I personally can't make any use of them.
by Huge
Wed Aug 29, 2018 3:19 am
Forum: Exodus
Topic: Exodus 2.1 release soon (Now available!)
Replies: 40
Views: 5478

Re: Exodus 2.1 release soon

Nemesis wrote:
Wed Aug 29, 2018 12:09 am
So, anything else? :)
Yeah, Saturn emulation :D
by Huge
Tue May 01, 2018 10:30 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

Actually... if the VDP1 is shrinking a texture, and there are transparent and opaque texels "overlapping" in a given place, does the opaque texel always get drawn? (i.e. does it write to the same pixel on the framebuffer multiple times within a line?) I think it is different in each mode. With Scal...
by Huge
Tue May 01, 2018 10:17 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

When reading doc and forums, I understand VDP1 will adapt texture to polygon. It polygon is 32x32 and texture 64x64, I understand will shrink texture to 32x32 and then change shape to adapt to polygon shape. But you wrote that will "show only 32x32 and then waste time checking pixels that don't end...
by Huge
Tue Apr 24, 2018 11:01 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

You'd need to do quite some magic to "defragment" your sprite table in a way like that, although I suppose it is possible, especially if you use very large sprites. But I don't think it's practical because for animation-heavy games, the VRAM is not enough and you need to load new sprites from low ra...
by Huge
Tue Apr 24, 2018 2:32 am
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

End codes are just Sega's idea of speed optimization. They tell the VDP1 to stop sampling the texture, so if large parts of the texture are transparent, you can get a potentially significant speedup at drawing.
by Huge
Sun Apr 22, 2018 8:58 pm
Forum: Hardware
Topic: Some questions about Saturn HW
Replies: 25
Views: 4576

Re: Some questions about Saturn HW

Though after working on some software polygon routines meant to draw Saturn-like quads I'm left baffled as to why it needs to go through all pixels (is bresenham-like interpolation that hard to do in hardware? serious question), not sure what it's doing internally on that respect. It goes through e...