I'm trying several different ways, but there are problems. I tried "Scope~" but the resolution is not good enough. Things look blocky at ~20Hz frequencies, nevermind higher frequencies. I tried ScopeXYZ~ in GEM, with a sawtooth wave for the x-coordinate and a sine wave for the y-coordinate, but it's flickering too much and there's no simple way to have a triggering mechanism. (I was thinking about just using a table with tabsend~, but I don't know how I'd get it to refresh fast enough or to select only the 64 points after the signal crosses the trigger level.)

I've attached a file with my two attempts. Any suggestions?

http://www.pdpatchrepo.info/hurleur/oscilloscope_test.pd

I was looking at the Chebychev polynomials mentioned in one of the tutorial patches, which can double, triple, etc. the frequency of a pure sine wave of amplitude 1. I wondered what would happen if I were to do this over and over again in a delay loop, so I created this patch. If you have the input frequency low (say, <1Hz) and the delay time low (I made it as low as possible, about 1-2ms) and if you use the higher-order Chebychev polynomials, then you get really weird, chaotic behavior.

http://www.pdpatchrepo.info/hurleur/FX_74a_-_iterative_chebyshev.pd

The pdpedia main page keeps getting spam. Could someone with the power to do so protect this page?

http://users.wpi.edu/~joausc/T2sounds.wav

This is a sound clip from a game boy game. I'm trying to figure out how I would make these sounds from scratch, but so far I don't have much luck. From the waveform (here's a part of it: http://users.wpi.edu/~joausc/waveform.bmp ) I can see that it's a pulse wave which varies randomly, decaying over time. I've tried creating a signal that oscillates randomly between the values of -1 and +1, but this sounds indistinguishable from white noise. Does anyone know how I could recreate the sounds I linked to above from scratch?

Didn't load here either. I use Pd version 0.40.3-extended-20080721 in Windows XP. Windows Task Manager showed that it was using around 100 MB ram and virtual ram, and that the CPU for pd was about 100%.

@arif said:

begs to ask, if one must have their oscilloscope presented by Pd?

If you can think of a good, free oscilloscope program, let me know. I'm choosing pd since it seems like a basic enough thing for someone to have created it.

Thank you all for your help. The samphold~ thing seems to do the trick, producing a sound that sounds much closer to the clip I posted than white noise. It sounds a little bit shakier than the clip, though, but this is a good start.

@nestor said:

I think what you're looking at IS the noise function, which seems to be the largest portion of the sample you posted. Perhaps the noise function is just as you described it, a random "flip-flop."

Near the end of the clip, there are some noise hi-hat sounds which seem to be actual noise, varying randomly within a range as opposed to most of the sounds which oscillate between two values. It seems strange that sounds in a "noise channel" can either be actual noise or just a random pulse wave. With 44100 Hz white noise I can't tell the difference, though at a lower sampling rate the pulse wave sounds a bit sharper.