Re: MIDISynth tool programming questions

[chuckie@sage.cc.purdue.edu (Gunn, C Stephen)]

In article <9301202146.AA15488@physics.wm.edu> 
           wrh@PHYSICS.WM.EDU (William Hall) writes:


>1. In order to use a MIDI driver, it must be loaded into memory (by me).  By
>  looking through the synthLab code, I found that this must be done by a 
>  system loader call.  Where can I find the documentation for the system
>  loader?  (Possibly GS/OS Ref?)

Yes. The documentation on the System Loader is in the GS/OS Reference. The 
call that you probably want to use is _InitilLoad2.
 
>2. In synthLab, there are volume settings for each individual instrument, set
>  by sliders in the volume setup screen.  What do these settings change?
>  (i.e., what call can I make in my program to set these levels?)

I don't know offhand. Let me check in the System 6.0 ref...

Ok.. From a quick glance I believe it is probably setting the volumeA and
volumeB entries in the wavelist record for the wave-range you have selected.
This "record" is defined on Page 129 of the System 6.0 Reference.

>3. According to the SetTempo call, the tempo range is 10-265 BPM with the
>  parameter to the call ranging from 0 to 255 (BPM-10).  So how come synthLAB
>  takes the tempo value stored in a song file, subtracts 5, and then multiplies
>  the result by 2?

Dont know on this one. However maybee synthlab stores the value /2 for some
reason. Perhaps it only wants you to do tempo's in increments of two. Or maybee
it is because you have the "Half Note" Set to be One Beat....

>4. How exactly do I check whether AppleTalk is enabled before I start the
>  MIDISynth tool?  The MIDISynth ERS and Programmer's Ref. for System 6.0 both
>  mention that my program must check to make sure AppleTalk is not enabled.

Check out Technical Note #18. "SCC Access" It presents a method for finding
out of the AppleTalk Main Driver is loaded, and what Serial Port it is using.
Since you don't need to clear a serial port for use, you just need to do a
_DINFOGS call on all devices, and look for the device type of "AppleTalk Main
Driver" If you find it, then appletalk is running.


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