Q: Setting pitch in speech-manager

[Michael O'Donnell <mick@ee.su.oz.au>]

I am trying to write a function to set the default-voice pitch for the 
speech-manager. However, lacking experience with traps and pointers,
I am horribly confused.  The following are the trap definitions
from the library source 'speech.lisp':

(deftrap _GETSPEECHPITCH ((CHAN (:POINTER :SIGNED-LONG)) (PITCH :POINTER))
   (:STACK :SIGNED-INTEGER)
   (:STACK-TRAP #xA800 :D0 (+ (ASH 1104 16) 12) CHAN PITCH))

(deftrap _SETSPEECHPITCH ((CHAN (:POINTER :SIGNED-LONG)) (PITCH :SIGNED-LONG))
   (:STACK :SIGNED-INTEGER)
   (:STACK-TRAP #xA800 :D0 (+ (ASH 1100 16) 12) CHAN PITCH))


 The first trap is easy to code for: the following seems to work:

(in-package :speech)

(defun get-speech-pitch nil
  (rlet ((Pitch :SIGNED-LONG))
     (traps::_GETSPEECHPITCH speech::*Default-Speech-Channel* Pitch)
     (%get-signed-word Pitch)))

;(get-speech-pitch) => 43 (male voice) 64 (feamle voice)


  I can't get a set-speech-pitch function to work. I tried many variations
on the following:

(defun set-speech-pitch (pitch)
  (traps::_SETSPEECHPITCH  *Default-Speech-Channel*  Pitch))

;(set-speech-pitch 55)
;(get-speech-pitch) => 1

 Can someone tell me what I am doing wrong? Thanks for any help,

Mick O'Donnell
University of Sydney