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PC speaker
Hi--
I'm running version 3 of RTLinux and it works great. The only minor nit
I have is that the beep on my IBM compatible pc speaker is just a low
buzzing sound instead of the usual 750Hz. I've tried using the console
escape sequences to raise the frequency of the beep, but although this
works fine when not running RTLinux, it doesn't appear to change the
frequency with RTLinux. Trying the same thing with the beep duration
works fine.
From what I understand of how the pc speaker circuitry works, a timer is
programmed with the frequency, and the connection to the speaker is then
enabled and later disabled, producing a beep. Is this timer being used
internally by RTLinux??
My application is a loop that gets control every 10ms for about 1-2ms.
Anyone know how I can get the beep back?
Andy
----------------- XOLD(K,IC,I)=
Andy Vaught .... DO ITERS=1, 10 XOLD(K,IC,I)
andy@xena.eas.asu.edu | | /CALLMSOLVE(A,B,X,I,ITERS,TOL)+(RANNYU(0)
Arizona State University ======|WRITE(6,'(I5,2X,F12.6)')ITERS,TOL -HALF)
Tempe, Arizona USA OOOOOO \ENDDORETURN PARAMETER(ZERO=1.D0)*TENTH*DELTA