# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1511213674 -3600
# Node ID f62fdab8f5b0b5d9bb810f338e3a78e3bc7cf545
# Parent  64f326c52ab144cc3ec0e303d54e968b5cafd020# Parent  c9ec1da2c3ca0c897958ae60eb30f189193fba46
Merged changes from a parallel development branch.

diff -r 64f326c52ab1 -r f62fdab8f5b0 vga.S
--- a/vga.S	Mon Nov 20 22:19:13 2017 +0100
+++ b/vga.S	Mon Nov 20 22:34:34 2017 +0100
@@ -553,12 +553,10 @@
 	occurs:
 	DCHxECON<15:8> = CHSIRQ<7:0> = timer 2 interrupt
 	DCHxECON<4> = SIRQEN = 1
-
-	For now, however, prevent initiation by not setting SIRQEN.
 	*/
 
 	la $v0, DCH0ECON
-	li $v1, (9 << 8)
+	li $v1, (9 << 8) | (1 << 4)
 	sw $v1, 0($v0)
 
 	/*
@@ -689,11 +687,7 @@
 	li $v1, (1 << 28)	/* IEC1<28> = DMA0IE = 1 */
 	sw $v1, SET($v0)
 
-	/* Enable line channel. */
-
-	la $v0, DCH0CON
-	li $v1, 0b10000000
-	sw $v1, SET($v0)
+	/* Enable line channel later. */
 
 	jr $ra
 	nop
@@ -907,8 +901,8 @@
 
 	/* Enable the line channel for timer event transfer initiation. */
 
-	la $v0, DCH0ECON
-	li $v1, (1 << 4)	/* DCH0ECON<4> = SIRQEN = 1 */
+	la $v0, DCH0CON
+	li $v1, (1 << 7)
 	sw $v1, SET($v0)
 
 _vbp_active_ret:
@@ -932,8 +926,8 @@
 
 	/* Disable the line channel. */
 
-	la $v0, DCH0ECON
-	li $v1, (1 << 4)	/* DCH0ECON<4> = SIRQEN = 0 */
+	la $v0, DCH0CON
+	li $v1, (1 << 7)
 	sw $v1, CLR($v0)
 
 _visible_active_ret: