# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1496005865 -7200
# Node ID d7298bd864252ecdae537bd434a983600e270dfc
# Parent  647180a1278b44b2a5f0ce1cb000f49496db5521
Transition between the picture and the pattern.

diff -r 647180a1278b -r d7298bd86425 vga.S
--- a/vga.S	Sun May 28 22:02:02 2017 +0200
+++ b/vga.S	Sun May 28 23:11:05 2017 +0200
@@ -161,21 +161,46 @@
 
 	/* Main program. */
 
-	li $a1, 5000000		/* counter = 5000000 */
+	li $a1, (3 << 24)	/* counter ~= 50000000 */
+	li $a2, 0xffffff	/* test counter at every 1/4 of range */
+	move $t2, $zero		/* picture to show */
 
 	/* Monitoring loop. */
 loop:
 	addiu $a1, $a1, -1	/* counter -= 1 */
-	bnez $a1, loop		/* until counter == 0 */
+	and $t1, $a2, $a1
+	bnez $t1, loop
 	nop
 
-	li $a1, 5000000		/* counter = 5000000 */
-
 	la $t0, PORTA
 	li $t1, (1 << 3)	/* PORTA<3> = RA3 */
 	sw $t1, INV($t0)
 
+	bnez $a1, loop		/* until counter == 0 */
+	nop
+
+	bnez $t2, _picture1
+	nop
+
+	/* Show picture 0. */
+
+	la $a0, screendata
+	jal init_framebuffer
+	nop
+	li $t2, 1
+	j _next
+	nop
+
+_picture1:
+	/* Show picture 1. */
+
+	jal init_framebuffer_with_pattern
+	nop
+	move $t2, $zero
+
 _next:
+	li $a1, (3 << 24)	/* counter ~= 50000000 */
+	li $a2, 0xffffff	/* test counter at every 1/4 of range */
 	j loop
 	nop