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--- sd:getting_stuff_done_in_assembly_language [2026/06/01 05:45] – appledog
+++ sd:getting_stuff_done_in_assembly_language [2026/06/01 14:44] (current) – appledog
@@ Line 127: / Line 127: @@
 <codify armasm>
+; Example 4: Random Numbers
 .address $C000
@@ Line 208: / Line 210: @@
 <codify armasm>
+; Example 5: Menus and Colored Text
 .address $C000
@@ Line 221: / Line 225: @@
     INT $10
-    LDAH $50
+    LDAH $50    ; Set teletype text default color
     LDAL $2F    ; color data in AL: BG=2, FG=F (here, orange)
     INT $10
@@ Line 229: / Line 233: @@
     INT 0x05
-    LDAH $50
+    LDAH $50    ; Set teletype text default color
     LDAL $29    ; color data default for mode 1
     INT $10
@@ Line 269: / Line 273: @@
 <codify armasm>
+; Example 6: The Cursor
 .address $C000
@@ Line 320: / Line 326: @@
 <codify armasm>
+; Example 7: put_ccxy
 .address $C000
@@ Line 351: / Line 359: @@
     RET
 </codify>
 == DEFCHAR Graphics
 Mode 1 Graphics is the first step in our graphics adventure. Mode 1 Graphics has two limitations. One, since you are redefining the character set to do graphics, everything must be drawn using 8x8 monocolor stamps (like characters). Two, you can only have 256 of them.
@@ Line 378: / Line 387: @@
 <codify armasm>
+; Example 8: DEFCHAR
 .address $C000
@@ Line 401: / Line 412: @@
 Unfortunately, the conversion to a smiley is permanent! At least, until you reboot the system (or change it back).
-=== put_ccxy
-Let's make a combo function that puts a character and a color on the screen at the same time. We'll use the non-cursor version of these functions:
-.address $C000
-start:
-    LDB #'A'
-    LDC $03
-    LDX #39
-    LDY #24
-    CALL @put_ccxy
-    RET
-; put_ccxy(B, X, Y, C)
-; Put Character and Color at X, T
-; INPUT:
-;     B -- ascii code
-;     X -- x location on screen
-;     Y -- y location on screen
-;     C -- hi nibble (BG) and low niblle (FG)
-;
-put_ccxy:
-    LDAH $11    ; Write character in B at X, Y
-    INT $10
-    LDAH $13    ; Set color in C at X, Y
-    INT $10
-    RET
-</codify>
-It's really a toss-up if you want to make two INT calls or just call put_ccxy. This is more about learning how those two functions can work.
 === Using this concept in Mode 3
@@ Line 453: / Line 429: @@
 <codify armasm>
+; Example 9: stamp_char
 .address $C000
@@ Line 543: / Line 521: @@
 The way to do multicolor graphics is to use different tiles for each color component. For example, you can have one tile with the blue pixels and the other tile with the yellow pixels. When you draw the tiles on top of each other, it will produce a multicolor effect.
+== Music
+Randomly, in the middle of nowhere, we will explain to you; yes, you can play music in your game. Our PLAY statement is multi-voice; please see the relevant documentation for more information. For now, here's a short little ditty reminiscent of England in the summer of the 1600's.
+<codify BASIC>
+PLAY "XV1 MN W5 XP3000 O4 L4 T180"
+PLAY "XV2 MN W5 XP3500 O3 L4 T180"
+PLAY "XV1 F1"
+PLAY "XV2 R1"
+PLAY "XV1 A4. B-8 > C4 C4 <"
+PLAY "XV2 R1"
+PLAY "XV1 B-4 A4 G4 F4"
+PLAY "XV2 R1"
+PLAY "XV1 > C2 C4. C8 <"
+PLAY "XV2 R2 F4. F8"
+PLAY "XV1 > C4 D2 C4 <"
+PLAY "XV2 F4 < B-2 A4"
+PLAY "XV1 B-4 A4 G4 G4"
+PLAY "XV2 B-4 F4 > C4 C4"
+PLAY "XV1 A1"
+PLAY "XV2 < F1"
+</codify>
+Now you may wonder, why incorporate a BASIC example? Here, we can use BASIC to quickly test musical ideas. When it's time to put them into a game, we do this:
+<codify armasm>
+; Example 10: Music
+.address $C000
+    LDELM @fair_phyllis
+    LDAH $52        ; Play Song
+    INT $11
+    RET
+fair_phyllis:
+    .bytes "XV1 MN W5 XP3000 O4 L4 T180"
+    .bytes "XV2 MN W5 XP3500 O3 L4 T180"
+    .bytes "XV1 F1 "
+    .bytes "XV2 R1 "
+    .bytes "XV1 A4. B-8 > C4 C4 < "
+    .bytes "XV2 R1 "
+    .bytes "XV1 B-4 A4 G4 F4 "
+    .bytes "XV2 R1 "
+    .bytes "XV1 > C2 C4. C8 < "
+    .bytes "XV2 R2 F4. F8 "
+    .bytes "XV1 > C4 D2 C4 < "
+    .bytes "XV2 F4 < B-2 A4 "
+    .bytes "XV1 B-4 A4 G4 G4 "
+    .bytes "XV2 B-4 F4 > C4 C4 "
+    .bytes "XV1 A1 "
+    .bytes "XV2 < F1", 0
+</codify>