Search found 92 matches

by foobat
Fri Dec 14, 2012 1:26 am
Forum: Cartridge
Topic: custom co-processor chips like the SVP?
Replies: 94
Views: 28273

What's the point of all that nonsense? At what point are you not really using the Megadrive/Genesis anymore? IMO this is just like taking a perfectly good gun and strapping plastic "modern warfare" crap to it
by foobat
Tue Dec 04, 2012 10:04 am
Forum: Sound
Topic: SN76489 Hardware Question - Can't get this to work
Replies: 6
Views: 3437

Looks like you need to press the button on the right at 3.57mhz. You're probably not pressing it fast enough lol edit: Aww it's upside down well that's a lot less funny now :( I guess I can try to be helpful absolute maximum rating for output current @5.5V is 2mA on pin 4 for the SN76489, is 2mA eno...
by foobat
Fri Nov 30, 2012 3:52 am
Forum: Sound
Topic: Convert Yamaha DX7 Patches to YM2612 format?
Replies: 18
Views: 6326

What do you do with the 2 extra operators? Ignore them? An Operator can be used or not. It's entirely up to the Musician what he does with each Operator. However, having more Operators gives the Musician the Potential to create more sonically rich Sounds. With FM one must be very very careful as it...
by foobat
Thu Nov 29, 2012 3:04 am
Forum: Sound
Topic: YM2612 output buffer
Replies: 11
Views: 4542

From http://code.google.com/p/bizhawk/source/browse/trunk/BizHawk.Emulation/Sound/YM2612.Timers.cs?r=2235 The master clock on the genesis is 53,693,175 MCLK / sec (NTSC) 53,203,424 MCLK / sec (PAL) 7,670,454 68K cycles / sec (7 MCLK divisor) 3,579,545 Z80 cycles / sec (15 MCLK divisor) YM2612 is fed...
by foobat
Thu Nov 29, 2012 2:39 am
Forum: Sound
Topic: Convert Yamaha DX7 Patches to YM2612 format?
Replies: 18
Views: 6326

What do you do with the 2 extra operators? Ignore them?
by foobat
Wed Nov 28, 2012 1:19 am
Forum: Sound
Topic: Convert Yamaha DX7 Patches to YM2612 format?
Replies: 18
Views: 6326

Don't even try to aproximate. You can go from ym2612->DX7 but not the other way around, it just can't happen.
by foobat
Tue Nov 27, 2012 3:17 am
Forum: Sound
Topic: YM2612 output buffer
Replies: 11
Views: 4542

The YM2612 has an integrated DAC so it's hard to tell exactly what's going on in-between the signal generator and the DAC. The YM2612 does operate at a fraction of its input clock (it's scaled down internally somewhere from 7.67... mhz). The input clock of the DAC is the internal clock of the ym2612...
by foobat
Mon Nov 26, 2012 4:12 am
Forum: Sound
Topic: YM2612 write/read/register select
Replies: 33
Views: 10833

Try http://depositfiles.com/files/3s7w4dyks for now. I'm in #spoon on irc.quakenet.org if you want to ask anything, but I might be afk. I'm doing midi semi-wrong (a big case statement instead of callbacks) edit: oh, also, this uses two YM2612s, hence the 12 channels. It keeps the data bus for the ym...
by foobat
Mon Nov 26, 2012 3:34 am
Forum: Sound
Topic: YM2612 write/read/register select
Replies: 33
Views: 10833

my code is whoa nasty now, it's a full-on VGM player and MIDI synthesizer that alters registers based on midi control codes so it might not be too useful to you anymore. I also had a power supply failure that took down my file server so those links will be dead until I get it back in order. I think ...
by foobat
Fri Nov 16, 2012 8:50 am
Forum: Blabla
Topic: Spartan-3 Board
Replies: 8
Views: 2567

time to learn verilog

good luck soldier
by foobat
Fri Nov 16, 2012 1:33 am
Forum: SGDK
Topic: Is there a SGDK suite? What would it look like?
Replies: 35
Views: 9015

I didn't mean to derail the thread, I'm just bikeshedding. But I do think Windows is a dying platform and I wouldn't tie a tutorial tool to it. Your target audience is either already experimenting with Linux or will be soon. Having to deal with make for windows and environment variables and mingw is...
by foobat
Thu Nov 15, 2012 8:36 pm
Forum: SGDK
Topic: Is there a SGDK suite? What would it look like?
Replies: 35
Views: 9015

Setting up a development environment in Windows is like pulling teeth. Some IDEs might do it acceptably (Code::Blocks does a good enough job) but if you need to teach someone how to use a dev kit do you want them learning a new IDE at the same time? It's easier to just stop thinking about the Window...
by foobat
Thu Nov 15, 2012 9:51 am
Forum: SGDK
Topic: Is there a SGDK suite? What would it look like?
Replies: 35
Views: 9015

Windows is holding you back, man. You gotta leave it behind
by foobat
Wed Oct 31, 2012 8:11 pm
Forum: Sound
Topic: z80 vgm player
Replies: 34
Views: 13193

The main cpu hog in VGM seems to be the wait instructions and PCM commands. If you can combine 3 or more consecutive 1-nibble wait instructions (0x7n commands in the VGM file) into one 2-byte wait instruction (0x61) you might be able to get much better performance. You can also usually combine conse...