# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1439754557 -7200
# Node ID 4f0db3c7456514a9558f8134f9668be46f824dfb
# Parent  c3c68373ee6d07f24ca24687c058dd9934fa32af
Added a subroutine to restore the previous interrupt handler.

diff -r c3c68373ee6d -r 4f0db3c74565 switcher.oph
--- a/switcher.oph	Sun Jun 28 23:30:02 2015 +0200
+++ b/switcher.oph	Sun Aug 16 21:49:17 2015 +0200
@@ -96,6 +96,7 @@
     ; return here with the initial main program stack
 
 main_end:
+    jsr restore_handler
     rts
 
 
@@ -125,6 +126,18 @@
 
 
 
+; restore the old interrupt handler address to IRQ1V
+;
+; affects: A
+
+restore_handler:
+    sei
+    .invoke mov16 old_handler, IRQ1V
+    cli
+    rts
+
+
+
 ; handle interrupts
 ;
 ; affects: (temporary stack usage)