Search found 88 matches

by Gigasoft
Mon Oct 27, 2014 10:00 pm
Forum: Sound
Topic: SMPS status ?
Replies: 11
Views: 2585

Really? Same? In sonicretro there are three different tables for three different SMPS versions for coordination flags. What I mean is that within any one of these versions, the format for music and sound effects is the same (except for the extra byte in the track header for which channel to use). W...
by Gigasoft
Fri Oct 24, 2014 11:45 pm
Forum: Megadrive/Genesis
Topic: Interruption mask
Replies: 2
Views: 1018

IRQ6: vblank
IRQ4: hblank
IRQ2: controller port TH pin
by Gigasoft
Fri Oct 24, 2014 10:56 pm
Forum: Sound
Topic: SMPS status ?
Replies: 11
Views: 2585

Strange, no info about ASDR here. I see that there is coordination flag for changing volume of PSG channel, but it's not ASDR support. May be it's another custom modification of SMPS? Well, not exactly ADSR, but there's something they call the "flutter table" which is just an arbitrary curve. And, ...
by Gigasoft
Fri Oct 24, 2014 6:28 pm
Forum: Sound
Topic: SMPS status ?
Replies: 11
Views: 2585

All playing music keeped in Z80 memory, so you have restriction on size of sequence. No, most games that use SMPS keep the music in ROM. The only game that I know of that loads it into Z80 RAM is Sonic 2. 6) PSG ASDR emulation. (correct me, if it's implemented in SMPS) Yeah, SMPS supports volume en...
by Gigasoft
Wed Oct 22, 2014 8:38 pm
Forum: Sound
Topic: General guidelines on working with PSG/YM2612 natively
Replies: 49
Views: 7623

Sonic 1 uses the Z80 exclusively for playing DAC samples, as does Phantasy Star 4. You also don't need to be reading things from ROM. The 68000 could write data into Z80 RAM as needed. For example, Sonic 2 has all its music in compressed form, and decompresses each tune into Z80 RAM before playing i...
by Gigasoft
Sat Aug 16, 2014 8:23 am
Forum: Megadrive/Genesis
Topic: Sonic speed ?
Replies: 7
Views: 1865

And why would it be laid out like that? Usually your levels are made out of larger tiles, and you only generate rows and columns of VRAM tiles when needed. Otherwise you run out of space fast. In the rare event that you do have a tilemap in ROM or RAM, it's probably still better to get the column da...
by Gigasoft
Wed Aug 06, 2014 5:41 pm
Forum: Megadrive/Genesis
Topic: Emulator-dependant bug
Replies: 7
Views: 1491

Looks like you are failing to synchronize accesses to the VDP. Make sure that you don't get interrupted in the middle of accessing the VDP by code that also accesses the VDP. Data uploads should preferably happen during blanking.
by Gigasoft
Tue Jul 15, 2014 12:14 pm
Forum: Sound
Topic: Need help w/YM2413
Replies: 4
Views: 1627

I can't see any problem with the calculation. Could you be reading the VGM file wrong?
by Gigasoft
Thu May 01, 2014 1:50 pm
Forum: Tools
Topic: Gigasoft Sound Engine 2
Replies: 5
Views: 1859

At one point I was thinking of making a MIDI converter, but got stuck trying to think of how to optimize the use of the staccato command vs. rest notes while at the same time making the best use of loops. So, I went for a text-based input language instead, as a step up from writing my songs using .d...
by Gigasoft
Thu May 01, 2014 1:08 pm
Forum: Video Display Processor
Topic: Confused about VRAM nametables (tiletables) sizes
Replies: 6
Views: 2240

Obviously, Sonic 1 doesn't use 64x64 nametables, so there's no problem.
by Gigasoft
Sat Apr 26, 2014 8:48 pm
Forum: Megadrive/Genesis
Topic: Assemblers You Use
Replies: 31
Views: 5307

I use TASM (Telemark Assembler) for Z80. Generating an output that can be modified and then reassembled is extremely challenging, due to the need to locate all pointers. They can be in the immediate operand of an instruction, they could be in a table, they could be structure members in a table of st...
by Gigasoft
Thu Apr 24, 2014 5:33 pm
Forum: Demos
Topic: wolfenstein demo for sega genesis
Replies: 350
Views: 91853

Well, you're only clearing $ff0000-$ffe000 at the start. Any reason for that?
by Gigasoft
Tue Apr 15, 2014 3:09 pm
Forum: Demos
Topic: Hide the Baby for Sega CD
Replies: 7
Views: 2749

Or use GSE2, which I just released (see the Tools section).
by Gigasoft
Tue Apr 15, 2014 2:51 pm
Forum: Tools
Topic: Gigasoft Sound Engine 2
Replies: 5
Views: 1859

Update:
Added support for playing sound effects simultaneously with music. (Press Start in test program to hear)
Slightly adjusted the levels in the demo song.
by Gigasoft
Tue Apr 15, 2014 9:37 am
Forum: Sound
Topic: Dual-YM2612 hardware synthesizer
Replies: 53
Views: 17219

My suggestions: - Do not map MIDI channel numbers to FM channels. Any FM channel is as good as any other, and it's up to the synth to make good use of them all. If I press 12 keys on my keyboard I just want to hear 12 notes sounding. - Use two YM2612s rather than two slightly dissimilar chips. - You...