SpritesMind.Net

Now, that's much better isn't it. :)

http://i44.tinypic.com/fw7rsn.jpg

I see now that the Sonic 2 character sprites are still written to the same place in VRAM in double-res mode (around 0xF000), but they are also now two tiles high.

(I used Exodus to have a peek at the memory - such a useful ...

Ahhaaaaa.... fixed the backgrounds!! :D

Funny how a fresh look at things can often help...

when BGAC_CALC_Y =>
BGA_COLINFO_WE_A <= '0';
if WIN_H = '1' or WIN_V = '1' then
BGA_Y <= "00" & Y;
else
if BGA_POS(9) = '1' then
BGA_Y <= (VSRAM(0)(9 downto 0) + Y) and (VSIZE & "11111111");
else ...

I spoke too soon with the results of the last code change.
Looks like the scroll values are still messed up or something?

The nametable addresses look like they're wrapping as well, as if I need to divide some values by two (limit the scroll range, due to using half the screen height?

The lower ...

This is an interesting interview.

I'm sure the theoretical Super MegaDrive could actually be made to run on the FPGA, but it sounds like they will be using the original sources of the games to compile as 3DS code?

So, it's not likely that we'd be able to easily extract the 3D modified versions of ...

No problem at all. :)

It's been good to use my brain and try to work it out.

Not done yet though, looks like the scroll values will need changing too?

Just compiling and trying the sprite address as well, but I'm not sure quite how the sprite engine works yet. I've added the interlace stuff like ...

Ahaaaa!!

Got it now. :D

Tiles in background mode are properly displayed now....

The scroll values and sprites still need to be fixed, but it's a lot better.

Just needed that one sentence from Nemesis...

"When you specify a block number in your mapping data for each layer, you're specifying the ...

LOL

Surprised that people wanted to poke the YM chip first?
Maybe it was due to it's sexy tones?

I only just found this thread - Nemesis to the rescue again!...

viewtopic.php?p=15708

Having a read through now.

OzOnE.

Interesting.

I may have to make up some diagrams then, just to try to visualize some stuff better.

Has the VDP been decapped yet?

I was looking at the huge photos of the YM2612 last night. It's fantastic stuff, but the VDP would be even better.

Just seen your edit, Jorge....

The fpgagen core ...

OK, just to get this clear in my limited brain. LOL

When using the double-res interlaced mode, the tiles are accessed as 8x16 instead of 8x8, correct?

Does that mean that there is the same amount of tile data, it's just the way it "pairs" the tiles together that makes the difference?

Ohhhh, hang ...

I tried those code changes on the background A and background B stages, but it didn't appear to make any difference?

But, the software is still acting up, because with those relatively minor changes, it had some glitches on the normal graphics (nothing major), but also the audio wasn't working ...

Here's an example of where the VDP code grabs the tile base address (not including the testbench / debug stuff)...

when BGAC_BASE_RD =>
if BGA_DTACK_N = '0' then
BGA_SEL <= '0';
T_BGA_PRI <= BGA_VRAM_DO(15);
T_BGA_PAL <= BGA_VRAM_DO(14 downto 13);
BGA_HF <= BGA_VRAM_DO(11);
if BGA_VRAM_DO(12 ...

Thanks, Jorge,

I'm not sure why something like a direct assignment would normally work fine in Verilog?

Maybe it's something specific to VHDL?
I was looking all over the Web last night to see if I was doing the assignment right, and it seemed to be fine?

In verilog, the same sort of assignment ...

btw, the part at the bottom of that code was my attempt at starting to add the interlaced stuff....

HV <= HV_VCNT(8 downto 1) & HV_HCNT(8 downto 1) when IM = '0' else -- IM bit is 0 in Non-interlace modes.
HV_VCNT(8 downto 2) & HV_VCNT(9) & HV_HCNT(8 downto 1) when IM = '1'; -- Note: IM bit ...

Ok, thanks guys.

I've been going through the code today and trying to figure things out.

The tech manual says that Name Table entries (addr part) are normally 10-bits wide, but 11-bits wide in Interlaced mode...

http://emu-docs.org/Genesis/sega2f.htm

I've also put comments in the code for the ...

Here's an example of two player split-screen mode...

http://i41.tinypic.com/2wpthtt.jpg

Sorry it's a bit blurry due to the movement.

Also, the stupid camera battery ran out just afterwards (as you can see by the date on the photo, it's an OLD camera. lol)

Does anyone know how the interlaced ...