DMC channel

atari2600a · Post by **atari2600a** » Fri Nov 30, 2007 1:57 pm

Listen to Ms. Pacman's opening sound. But think about it, would 2 really offset tones really sound pleasant?

Post by **Memblers** » Fri Nov 30, 2007 3:02 pm

2600 has 2 channels, what I like about them is that they have this crazy-ass distortion setting (4-bit), one setting makes a square wave, the others range between noise and some combination of square + pseudo-random.

It's a shame the frequency range is horrible.

http://qotile.net/files/2600_music_guide.txt

DMC channel might do alright with some of them maybe, pulse channels would be pretty weak though for reproducing settings besides the square. The $4011 DAC would work good, of course.

Celius · Post by **Celius** » Fri Nov 30, 2007 5:27 pm

Ms. Pacman's intro song sounds like it could be easily replicated with the square waves. There are some really wierd sounds on 2600 games that could also be simulated with the noise channel.

BMF54123 · Post by **BMF54123** » Mon Dec 03, 2007 8:38 am

Trivia of the Day: Most of SMB2's DMC samples (Birdo hit, doors opening, etc.) are merely recordings of the original Doki Doki Panic FDS sounds.

[insert "The More You Know" logo here]

Bregalad · Post by **Bregalad** » Mon Dec 03, 2007 10:41 am

Same goes with Zelda (US/PAL) DPCM sound effects.

NotTheCommonDose · Post by **NotTheCommonDose** » Mon Dec 03, 2007 1:00 pm

BMF54123 wrote:Trivia of the Day: Most of SMB2's DMC samples (Birdo hit, doors opening, etc.) are merely recordings of the original Doki Doki Panic FDS sounds.

[insert "The More You Know" logo here]

Wow, that strikes me as more than surprised. How did you find that out?

Celius · Post by **Celius** » Mon Dec 03, 2007 6:34 pm

Celius wrote:EDIT: No, actually, I had a different ROM that was 1024k, and it had a DMC file in it, and it was really really nice sound. I remember that it was when I wasn't even into NESdev yet, and I was so blown away by the quality and I didn't know how it was even possible to do such a thing.

So yeah, I found what I was talking about in that post. It's some song spanned across multiple banks, I think it's about 2 minutes.

http://www.freewebs.com/the_bott/pcm.nes

Bregalad · Post by **Bregalad** » Tue Dec 04, 2007 9:07 am

I remember about that one. Of course playing a sample into $4011 is easy as long as it's not compressed and if the CPU does absolutely nothing during that time.

CKY-2K/Clay Man · Post by **CKY-2K/Clay Man** » Tue Dec 04, 2007 12:04 pm

atari2600a wrote:Curious, has anyone ever tried converting an entire song & slapping it into a ROM?

I've seen a PD ROM like this but the song was bleh.

BMF54123 wrote:Trivia of the Day: Most of SMB2's DMC samples (Birdo hit, doors opening, etc.) are merely recordings of the original Doki Doki Panic FDS sounds.

[insert "The More You Know" logo here]

Yeah, I've learned that when I played Zelda & Doki. Very simular.

NotTheCommonDose · Post by **NotTheCommonDose** » Tue Dec 04, 2007 1:22 pm

Bregalad wrote:I remember about that one. Of course playing a sample into $4011 is easy as long as it's not compressed and if the CPU does absolutely nothing during that time.

If I gave you a song could you make me a .NES rom out of it or can you make a program for that? It would be so 8) if you did!

Celius · Post by **Celius** » Tue Dec 04, 2007 2:04 pm

You should probably learn how to do that yourself. I would really like to see my game idea up and running, so I have to make it. So if you'd like to see a song sample of yours playing, I'd suggest making it yourself, because a lot of the people on this board don't have time to do their projects as well as someone else's.

Bregalad · Post by **Bregalad** » Tue Dec 04, 2007 2:22 pm

It's basically as simple as something like this :

Code: Select all

.org $8000
include "MySong.raw"

PlayDMC:
  ldy #$00
  sty Pointer
  lda #$80
  sta Pointer+1
- nop
  nop    (as many NOP as you want in function of the frequency)
  nop
  lda [Pointer],Y
((add potential decompressioon algorithm, format converting and end of sample checks here))
  sta $4011
  iny
  bne -
  inc Pointer+1
  bne -
etc....

NotTheCommonDose · Post by **NotTheCommonDose** » Tue Dec 04, 2007 2:27 pm

"etc...."? what? and what do I use to compile this? 6502.exe NESHLA? I''m very confused.

Post by **tepples** » Tue Dec 04, 2007 3:13 pm

NotTheCommonDose wrote:If I gave you a song could you make me a .NES rom out of it or can you make a program for that?

I could probably expand my $4011 demo to work with longer samples, but I can't fit more than 2 minutes into a 512 KiB (max mmc1/mmc3 size) file unless I use tricks like only storing the chorus once.

NotTheCommonDose · Post by **NotTheCommonDose** » Tue Dec 04, 2007 4:20 pm

I don't get what you mean now.