Path: utzoo!attcan!uunet!lll-winken!claris!scott
From: scott@claris.com (Scott Lindsey)
Newsgroups: comp.sys.apple
Subject: Re: GS SysBeep/border flash
Message-ID: <8220@claris.com>
Date: 20 Jan 89 20:58:21 GMT
References: <8901191217.aa11784@SMOKE.BRL.MIL>
Organization: Claris Corporation, Mountain View CA
Lines: 43

From article <8901191217.aa11784@SMOKE.BRL.MIL>, by AWCTTYPA@UIAMVS.BITNET ("David A. Lyons"):
 
> Not quite true--I don't want to be _too_ picky, but the difference
> is important.  The patch is actually to the Bell vector (get/set
> with GetVector and SetVector), as I said in another message.  The
> SysBeep toolbox call is at a higher level; it uses FWEntry to call
> the old Bell entry point at $FBDD, which eventually gets around to
> calling the bell vector and making the default "Bonk" if the routine
> returns with the carry flag set.  (At power-on, the bell vector just
> points at SEC RTL.)

OK, you're right about that... I responded without really thinking.

Here's some information that might be useful to people writing their own
bell routines:

It is possible to have a digitized beep that uses the pitch and volume
settings in the control panel.

You should be able to call _GetBParam to get these two values,
where 1E (User volume) is the bell volume and 1F (Bell volume) is the pitch.
This is the officially sanctioned method of doing this.  If your code is
particularly time dependant and you can't face the overhead of the _GetBParam
call (which is an expensive call), you might try these high memory locations
which are used by the beep in ROM, so they should be _fairly_ safe.  Note
that they are not documented and are presumably subject to change.

Pitch: $E102DF ($0..E) where 0 is low & $E is high
Volume:$E102DE ($0..E) where 0 is off & $E is loud

I have a beep routine (using speaker toggling) that uses these memory
locations without any problem under all of the system software (including 4.0)

If you want to retain the border flashing, you should be able to _GetVector
to get the current beep (which is the flash or nothing) and call it yourself
from your beep routine.


-- 
Scott Lindsey, wombat    | UUCP: {ames,apple,portal,sun,voder}!claris!scott
Product Development      | Internet:  scott@claris.com  |  AppleLink: LINDSEY1
Claris Corp.             | Disclaimer: These are not the opinions of Claris,
(415) 960-4070           | Apple, the author, or anyone else living or dead.