continuing with serial driver in dsa.

dsa_resources/animation.dsa

@@ -1,11 +1,20 @@
 dw DISPLAY: 0x30000
 dw stack: 0x10000
 
+// colour table — AABBGGRR format
+dw COL0: 0xFFFFFFFF   // white
+dw COL1: 0xFF0000FF   // red
+dw COL2: 0xFF00FF00   // green
+dw COL3: 0xFFFF0000   // blue
+dw COL4: 0xFF00FFFF   // yellow
+dw COL_IDX: 0
+
 // registers:
 // rg0 = x position
 // rg1 = y position
 // rg2 = x direction (1 = right, 0 = left)
 // rg3 = y direction (1 = down,  0 = up)
+// rg5 = current colour
 
 _init:
     ldw stack, bpr
@@ -16,17 +25,20 @@ start:
     lli 0, rg1
     lli 1, rg2
     lli 1, rg3
+    lli 0, rg8
+    stw rg8, COL_IDX
+    ldw COL0, rg5
 
 frame_loop:
     // --- clear display ---
     ldw DISPLAY, rg4
-    lwi 76800, rg5
+    lwi 76800, rga
 
 clear_loop:
     stw zero, rg4
     addi rg4, 4, rg4
-    subi rg5, 1, rg5
-    jnz rg5, clear_loop
+    subi rga, 1, rga
+    jnz rga, clear_loop
 
     // --- draw square ---
     mov rg1, rg6
@@ -36,7 +48,6 @@ draw_y_loop:
     add rg1, rg8, rg8
     ilt rg6, rg8, rg9
     jez rg9, draw_done
-
     mov rg0, rg7
 
 draw_x_loop:
@@ -44,7 +55,6 @@ draw_x_loop:
     add rg0, rg8, rg8
     ilt rg7, rg8, rg9
     jez rg9, draw_x_done
-
     shl rg6, 8, rg8
     shl rg6, 6, rg9
     add rg8, rg9, rg8
@@ -52,11 +62,7 @@ draw_x_loop:
     shl rg8, 2, rg8
     ldw DISPLAY, rg9
     add rg9, rg8, rg8
-
-    lli 0xFFFF, rg9
-    lui 0xFFFF, rg9
-    stw rg9, rg8
-
+    stw rg5, rg8
     addi rg7, 1, rg7
     jmp draw_x_loop
 
@@ -65,24 +71,28 @@ draw_x_done:
     jmp draw_y_loop
 
 draw_done:
-    // --- check x walls before moving ---
+    // --- track bounces this frame ---
+    lli 0, rgb
+    lli 0, rgc
+
+    // --- check x walls ---
     lli 1, rg8
     ieq rg2, rg8, rg9
     jez rg9, check_x_left_wall
 
 check_x_right_wall:
-    // moving right: if x >= 300 flip direction
     lli 300, rg8
     ige rg0, rg8, rg9
     jez rg9, move_x
     lli 0, rg2
+    lli 1, rgb
     jmp move_x
 
 check_x_left_wall:
-    // moving left: if x == 0 flip direction
     ieq rg0, zero, rg9
     jez rg9, move_x
     lli 1, rg2
+    lli 1, rgb
 
 move_x:
     lli 1, rg8
@@ -94,40 +104,59 @@ do_x_left:
     subi rg0, 1, rg0
 
 check_y_walls:
-    // --- check y walls before moving ---
     lli 1, rg8
     ieq rg3, rg8, rg9
     jez rg9, check_y_up_wall
 
 check_y_down_wall:
-    // moving down: if y >= 220 flip direction
     lli 220, rg8
     ige rg1, rg8, rg9
     jez rg9, move_y
     lli 0, rg3
+    lli 1, rgc
     jmp move_y
 
 check_y_up_wall:
-    // moving up: if y == 0 flip direction
     ieq rg1, zero, rg9
     jez rg9, move_y
     lli 1, rg3
+    lli 1, rgc
 
 move_y:
     lli 1, rg8
     ieq rg3, rg8, rg9
     jez rg9, do_y_up
     addi rg1, 1, rg1
-    jmp delay
+    jmp check_corner
 do_y_up:
     subi rg1, 1, rg1
 
+check_corner:
+    and rgb, rgc, rg8
+    jez rg8, delay
+
+    // advance colour index
+    ldw COL_IDX, rg8
+    addi rg8, 1, rg8
+    lli 5, rg9
+    ige rg8, rg9, rg9
+    jez rg9, store_col_idx
+    lli 0, rg8
+
+store_col_idx:
+    stw rg8, COL_IDX
+
+    // load colour from table: address = COL0 + idx * 4
+    shl rg8, 2, rg8
+    lwi COL0, rg9
+    add rg9, rg8, rg8
+    ldw rg8, rg5
+
 delay:
     lwi 2000000, rg8
 delay_loop:
     subi rg8, 1, rg8
     jnz rg8, delay_loop
-
     jmp frame_loop
 
-    hlt
+    hlt