That's pretty cool. The USA guys might not be familiar with the original Sinclair ZX Spectrum, but that had a 1 voice beeper, but musicians/coders did some amazing things with it. This guy does a detailed analysis on what they did
https://hackaday.com/2022/01/20/when-a-single-bit-was-enough-into-the-sound-of-the-zx-spectrum/?fbclid=IwAR2-g9QsikuuFz2eGhmPVT-p1KhYFZuXLaivcnafhtW__O9Sie1qU9a5YbM On Thu, Apr 7, 2022, 9:27 AM Stephen Adolph <[email protected]> wrote: > When I have looked at the buzzer circuit circuit in the past, I was always > wondering - could you drive 2 audio signals into the buzzer? > > > There are 3 signals that drive the buzzer. > > Port BA pin 5 - direct drive > Port BA pin 2 - on/off control for the "sound" tone > Timer signal - tone generator > > So, you can make sound 3 ways > 1) by enabling a single tone, enabling pin 2 and disabling pin 5 > 2) by enabling a single tone, and modulating pin 2, and disabling pin 5 > 3) by disabling single tone, disabling pin 2, and modulating pin 5. > > I ran a simple program to prove that you can generate extra sounds. > > 5 sound1000,1 > 10 out186,233 > 15 fori=1to1000:next > 20 call30326:goto20 > > (hit reset to get back to normal!!) > line 5 sets a tone > line 10 turns on pin 2; you hear the tone > line 15... some delay > line 20 rapidly toggles the direct drive at pin 5. new sounds! > > you can distinctly hear the two separate sounds. > In fact you can hear the timer interrupt as well, every second. > you can also hear keyboard inputs > > so, this little test shows that you could separately set up a single tone, > as well as driving modulated signal directly. that's 2 sounds > > A third sound could be mixed in by modulating pin 2 (turning the tone on > and off). > > I don't know of any M100 software that has taken advantage of these extra > ways to make sounds. Anyone else? > > Seems like an interesting area to explore. Some supporting machine code > routines would be interesting to think about. > > need to think of a clever way to demonstrate 3 sounds mixed. > > Steve > >
