Merge pull request #1962 from marianodominguez/feature_add_sound_command

add sound command

include/atari.h

@@ -235,6 +235,12 @@ extern void __fastcall__ _scroll (signed char numlines);
                                           /* numlines < 0  scrolls down */
 
 
+/*****************************************************************************/
+/*    Sound function                                                         */
+/*****************************************************************************/
+
+extern void  __fastcall__ _sound (unsigned char voice, unsigned char frequency, unsigned char distortion, unsigned char volume);
+
 /*****************************************************************************/
 /* Misc. functions                                                           */
 /*****************************************************************************/

libsrc/atari/sound.s

@@ -0,0 +1,37 @@
+;
+; Mariano Domínguez
+; 2022-12-4
+;
+; atari lib
+;
+        .include "atari.inc"
+        .export         __sound
+        .import         popa
+        .importzp       tmp1,tmp2
+
+; play sound, arguments: voice, pitch, distortion, volume. same as BASIC
+.proc   __sound
+        sta tmp2        ;save volume
+        jsr popa        ;get distortion
+        sta tmp1        ;save distortion
+        jsr popa        ;get pitch
+        pha             ;save in stack
+        jsr popa        ;get voice
+        asl a           ;adjust voice *2 for offset in x
+        tax
+        pla             ;get pitch from stack
+        sta AUDF1,x     ;store pitch
+        lda #0
+        sta AUDCTL
+        lda #3
+        sta SKCTL       ;init sound
+        lda tmp1        ;get distortion
+        asl a           ;ignore the high nibble
+        asl a
+        asl a
+        asl a
+        clc             ;setup for adding volume
+        adc tmp2      ;add volume
+        sta AUDC1,x     ;volume + distortion in control channel
+        rts
+.endproc

targettest/atari/Makefile

@@ -39,6 +39,7 @@ EXELIST_atari = \
         multi.xex \
         ostype.xex \
         scrcode.com \
+        sound.xex \
         sys.xex
 
 ifneq ($(EXELIST_$(SYS)),)
@@ -74,7 +75,8 @@ scrcode.com: scrcode.s
 	$(CL) -t atari -C atari-asm.cfg -o scrcode.com scrcode.s
 sys.xex: sys.c
 	$(CL) -t atari -o sys.xex sys.c
-
+sound.xex: sound.c
+	$(CL) -t atari -o sound.xex sound.c
 clean:
 	@$(DEL) charmapping.xex 2>$(NULLDEV)
 	@$(DEL) defdev.xex 2>$(NULLDEV)
@@ -85,3 +87,4 @@ clean:
 	@$(DEL) scrcode.o 2>$(NULLDEV)
 	@$(DEL) scrcode.com 2>$(NULLDEV)
 	@$(DEL) sys.xex 2>$(NULLDEV)
+	@$(DEL) sound.xex 2>$(NULLDEV)

targettest/atari/sound.c

@@ -0,0 +1,20 @@
+/*
+** Test program for _sound for atari
+**
+**  January 6 2023 Mariano Domínguez
+*/
+
+#include <stdio.h>
+#include <conio.h>
+#include <atari.h>
+#include <cc65.h>
+
+int main(void)
+{
+    int i=0;
+    printf("playing sound \n");
+    _sound(1,121,10,15); //voice, pitch, distortion, volume
+    for(i=0;i<9000;i++);
+    _sound(1,0,0,0); //silencing, same as Atari Basic
+    return 0;
+}