En/na Marco van de Voort ha escrit:
Naturally, this is not possible: The PC speaker is simply controlled
by a timer, which creates a square wave (on/off). In ancient DOS times
there was a trick by doing a frequency modulation, i.e. you turn the
timer on and off quite fast. But on Linux etc. the drivers don't
support such cheats.
<scratches chin> Hmmm... could you use that old Turbo Pascal code to do
an inline of the ASM for it? (talking completely through my hat having
never attempted such a thing on a linux platform)
Not really. It is not the asm or not, it is simply no hardware access from
programs in principle, one program not being able to lock the entire CPU to
modulate the speaker.
Of course you can, but then you go into the realm of customizing linux.
There's also the "pc-speaker" driver (though I never used it) that
already does it:
http://www.geocities.com/stssppnn/pcsp.html
Bye
--
Luca
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