Search found 2757 matches

by Chilly Willy
Tue Apr 30, 2019 4:19 pm
Forum: Super 32X
Topic: Using 32x as a 3rd plane, possible?
Replies: 28
Views: 3892

Re: Using 32x as a 3rd plane, possible?

Anyway, the boot rom of the 32x at the end jumps at whatever is in 0x24000020, what happens if there is nothing written there? I think you're misinterpreting the boot code. The boot code looks for a header in the rom that tells it things like where the data segment in the rom is, how big it is, whe...
by Chilly Willy
Fri Apr 26, 2019 2:37 pm
Forum: Super 32X
Topic: Using 32x as a 3rd plane, possible?
Replies: 28
Views: 3892

Re: Using 32x as a 3rd plane, possible?

Yes, there is... it's called - "SLEEP". :wink: SLEEP puts the SH2 in power down mode until an (enabled) interrupt arrives, which will wake the processor. Pretty standard stuff here. Oh, be sure you put the routine that sleeps in sdram as rom won't be available when RV = 0. And no one made dual carts...
by Chilly Willy
Tue Apr 23, 2019 3:46 pm
Forum: SGDK
Topic: MEM_alloc
Replies: 7
Views: 840

Re: MEM_alloc

In SGDK, a hard reset clears the work ram, then copies the data segment from rom into work ram (taking care of all those preset variables). A soft reset skips both those steps, so preset variables won't have their preset value, and the rest of memory won't be clear. Calling SYS_hardReset() forces a ...
by Chilly Willy
Tue Apr 23, 2019 3:34 pm
Forum: Sound
Topic: Some beginner questions concerning YM2612
Replies: 24
Views: 2664

Re: Some beginner questions concerning YM2612

1) Start here: https://en.wikipedia.org/wiki/Musical_note#12-tone_chromatic_scale Keep reading past the section on 'Note frequency (hertz)'. 2) Yes, those numbers are clearly wrong. The 372 should 672, and the 392 should be 713. The last two numbers are also clearly wrong. The first line are the maj...
by Chilly Willy
Mon Apr 22, 2019 7:41 pm
Forum: Demos
Topic: MD-NICCC - a 3D Mega Drive experience by TiTAN
Replies: 56
Views: 4952

Re: MD-NICCC - a 3D Mega Drive experience by TiTAN

Awesome demo! You guys really kick butt when pushing the MD. :D
by Chilly Willy
Wed Apr 17, 2019 1:19 pm
Forum: Cartridge
Topic: Size limits
Replies: 35
Views: 7313

Re: Size limits

128MB (1Gbit) of flash, and 2MB of save ram, IIRC. It uses the standard SEGA mapper with all 8 bits of the bank registers implemented. It uses level shifters to interface with the 3V parts. And that's it. Just a straightforward BIG flash cart. Jorge has a special box he made to flash carts like this...
by Chilly Willy
Tue Apr 16, 2019 11:58 pm
Forum: Cartridge
Topic: Size limits
Replies: 35
Views: 7313

Re: Size limits

Jorge is making a few Giga carts sometime this year. I've arranged to get two from him when he does.
by Chilly Willy
Sat Apr 13, 2019 9:37 pm
Forum: Tools
Topic: Update your Genesis/32X Toolchain!
Replies: 108
Views: 44728

Re: Update your Genesis/32X Toolchain!

Yes, the 32X doesn't have anything like SGDK. My 32X stuff is aimed more at mostly running off the 32X with the MD side just providing controller inputs and access to save ram/rom bank control. If that's fine for the game you want, the example code I provide for the 32X should be enough to get your ...
by Chilly Willy
Sat Apr 13, 2019 9:27 pm
Forum: Blabla
Topic: Where is your very first Megadrive/Genesis now?
Replies: 4
Views: 1004

Re: Where is your very first Megadrive/Genesis now?

I bought a Gen2 + CD2 back in 1992. It's sitting on a TV stand not 5 feet away from me. In 1994, I got a 32X for it, and it's all still working fine. I use it for most of my dev checking. The sound isn't as good as a CDX I got later, but it's good enough for testing.
by Chilly Willy
Fri Apr 12, 2019 12:31 pm
Forum: Tools
Topic: Update your Genesis/32X Toolchain!
Replies: 108
Views: 44728

Re: Update your Genesis/32X Toolchain!

My toolchain isn't designed around other devkits, it's designed around my own examples. I don't know the extent you would have to go to to make it work with something like code blocks, though it should be possible. My toolchain is more low-level and geared towards people who already know what they'r...
by Chilly Willy
Thu Apr 11, 2019 5:54 pm
Forum: Tools
Topic: Update your Genesis/32X Toolchain!
Replies: 108
Views: 44728

Re: Update your Genesis/32X Toolchain!

There isn't a binary arc of a pre-built version of this toolchain (I don't think there is), so you have to build it yourself. People have done this in Windows using minGW + msys as mentioned here: http://gendev.spritesmind.net/forum/viewtopic.php?p=12858#p12858 Once you have the toolchain built, you...
by Chilly Willy
Tue Apr 09, 2019 11:08 pm
Forum: Exodus
Topic: Active Disassembly - Post Processor
Replies: 14
Views: 981

Re: Active Disassembly - Post Processor

The manual is online here: http://www.pusher.dk/amiga/resource/manual/ It's not exactly a tutorial, but it does show you how to get started, and isn't hard to follow. There's also a python 680x0 disassembler someone is making to replace ReSource found here: https://github.com/rmtew/peasauce Haven't ...
by Chilly Willy
Tue Apr 09, 2019 3:58 pm
Forum: Exodus
Topic: Active Disassembly - Post Processor
Replies: 14
Views: 981

Re: Active Disassembly - Post Processor

Sounds like I should stick with ReSource for MD disassembly. :D

It handles all that rather well. You can't disassemble Z80 in it, but it does 680x0 like a charm. You'd have to make the Z80 parts binary blobs.
by Chilly Willy
Mon Apr 08, 2019 1:05 am
Forum: SGDK
Topic: Dummy question on button handling
Replies: 9
Views: 933

Re: Dummy question on button handling

The more the compiled code can keep commonly used variables in a cpu register, the faster the code will be. Small functions may only use a few registers, so the code that calls that function can leave common variables in registers not touched by the function and hence run faster. In the case of your...
by Chilly Willy
Sun Apr 07, 2019 9:12 pm
Forum: SGDK
Topic: Dummy question on button handling
Replies: 9
Views: 933

Re: Dummy question on button handling

It doesn't use all the registers. Look at the code void VDP_waitVSync() { vu16 *pw; pw = (u16 *) GFX_CTRL_PORT; while (*pw & VDP_VBLANK_FLAG); while (!(*pw & VDP_VBLANK_FLAG)); } That simply isn't going to clobber more than a couple registers. Also note the vu16 - that's a volatile unsigned 16 bit i...