From what I've come to understand, it's not the envelope that's being done with. The envelope effects all three channels at once. What's going on supposedly is that the volume control is being manipulated to create the different waveforms and to produce PWM. Part of doing PWM is also by doing VERY rapid arpeggio, I think? The Atari ST had a pretty fast CPU when it came out (8Mhz I think), so it was possible to rapidly perform these tricks in ways that the ZX Spectrum, Amstrad CPC line and MSX computers just could not.
@@railsrust PWM is done by matching the square's frequency with an identical (but inverted) square wave, but offsetting it slightly, and outputting that to the volume register. The ZXS and CPC can do this but it takes a lot more available CPU time.
@@ashkirby8896 I guess it might be usable on an individual channel, but it looks like most programmers didn't use it, instead opting for manipulating the volume to create waveforms. From Wikipedia: "As there was only one envelope shared between all three channels, many programmers ignored it and programmed their own envelope controllers in software (controlling volume directly)."
![[Atari ST] !Cube - Blipblop Memories (Oscilloscope View)](http://i.ytimg.com/vi/Wl7914giLTI/mqdefault.jpg)
![[Atari ST] !Cube - Blipblop Memories (Oscilloscope View)](/img/tr.png)
I didn't realize I needed sawpulse in my life.
AY-YYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
Rather YM-MMMMmmmmmmm :-)
lmao
nice video
woah
I guess it's resetting the envelope really quickly
(and the square wave part is just a normal square wave playing on that channel)
Wow😄🤩😎👌, how is the envelope alternating between the square wave channels super fast, and how is the square channel doing PWM?
From what I've come to understand, it's not the envelope that's being done with. The envelope effects all three channels at once. What's going on supposedly is that the volume control is being manipulated to create the different waveforms and to produce PWM. Part of doing PWM is also by doing VERY rapid arpeggio, I think? The Atari ST had a pretty fast CPU when it came out (8Mhz I think), so it was possible to rapidly perform these tricks in ways that the ZX Spectrum, Amstrad CPC line and MSX computers just could not.
@@railsrust PWM is done by matching the square's frequency with an identical (but inverted) square wave, but offsetting it slightly, and outputting that to the volume register. The ZXS and CPC can do this but it takes a lot more available CPU time.
I thought the envelope could only be used on only 1 channel at a time.
@@ashkirby8896 I guess it might be usable on an individual channel, but it looks like most programmers didn't use it, instead opting for manipulating the volume to create waveforms. From Wikipedia: "As there was only one envelope shared between all three channels, many programmers ignored it and programmed their own envelope controllers in software (controlling volume directly)."
Rails & Rust Ah, I see.😄 So people used it to manipulate the volume of the squares to make PWM?