use speakers
in [ASM]
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From: Alexei A. Frounze on 8 Feb 2010 00:02 On Feb 7, 4:47 pm, "wolfgang kern" <nowh...(a)never.at> wrote: > Alexei A. Frounze wrote: > > <q> > > >>>> for more 'musical' notes there is need to break them > >>>> in the way they are understendable. > >> there someone hear notes melody noises etc? > > this digital produced square-waves became distorted by the > > inductivity of a 'real' magnet-type speaker, so for a very > > small frequency-range it may even sound like sine-wave. > > newer machines got just cristal-beepers, so the square-wave > > will reach your ears almost unfiltered. > > Don't newest notebooks simply use the same speakers for both > functions? > </q> > > I haven't checked on details yet, but when I hear BIOS beep > this sound quite different than the usual stereo-'notify.wav'. > > Even possible, I daubt that a mobile BIOS emulate > port 61h+42h or use the onboard soundchip or direct gate the > speaker(s) just for a beep. > > The 'BIOS'-Beep got a meaning and it's direct gated, > ie: permanent sound if fatal mainboard errors like missing > clock or no CPU, or no ROM or no RAM inserted ... Yes, they could either use the sound chip's input or connect directly to the speaker(s). Either way, I don't think a dedicated beep speaker is needed in notebooks. Alex
From: wolfgang kern on 8 Feb 2010 14:23 Alexei A. Frounze wrote: <q> >>>>> for more 'musical' notes there is need to break them >>>>> in the way they are understendable. >>> there someone hear notes melody noises etc? >> this digital produced square-waves became distorted by the >> inductivity of a 'real' magnet-type speaker, so for a very >> small frequency-range it may even sound like sine-wave. >> newer machines got just cristal-beepers, so the square-wave >> will reach your ears almost unfiltered. > Don't newest notebooks simply use the same speakers for both > functions? > I haven't checked on details yet, but when I hear BIOS beep > this sound quite different than the usual stereo-'notify.wav'. > Even possible, I daubt that a mobile BIOS emulate > port 61h+42h or use the onboard soundchip or direct gate the > speaker(s) just for a beep. > The 'BIOS'-Beep got a meaning and it's direct gated, > ie: permanent sound if fatal mainboard errors like missing > clock or no CPU, or no ROM or no RAM inserted ... Yes, they could either use the sound chip's input or connect directly to the speaker(s). Either way, I don't think a dedicated beep speaker is needed in notebooks. </q> Ok, next time when I have one in hand I'll take it as apart, just to see the truth :) __ wolfgang
From: Nathan Baker on 26 Feb 2010 15:00
"wolfgang kern" <nowhere(a)never.at> wrote in message news:hkhthq$d3p$1(a)newsreader2.utanet.at... > > TYhe story of PC-Music is quite old, and the very first attempts > to produce music and aslso good understandable voice-streams by > passing it to the PC-speaker were really astonishing. > >> i have no study music but it seems to me that there is something of kind >> >> |-------|---|--------|-------| > > the sound of computer music always were: > > attack/decay/pause/ > > OLDe Standard Sound worked with 'attack'/'decay'-commands > like the well know C64-sound. > I remember it being 4 parts: attack/decay/sustain/release. This was a rudimentary (but effective) method of allowing the programmer to determine the shape of an individual note. I'd imagine that to simulate a sawtooth-like hum, you'd set a relatively gradual attack, a sharp decay and release, and a 0 amplitude sustain. Then you'd probably fire-off several of these same-shaped notes in rapid succession to obtain the 'hum' effect. There is a cross-platform library that seems to provide a different approach to shaping the waveform: http://www.portaudio.com/ Also, for fans of the old 'built-in' PC-speaker, the is a library for specifically playing chiptune sounds ("beep the beeper" as Betov would say): http://github.com/whymirror/bloopsaphone#readme Nathan. |