diff --git a/build/simh/boot b/build/simh/boot
index 270172d9..8ed4b23c 100644
--- a/build/simh/boot
+++ b/build/simh/boot
@@ -3,4 +3,7 @@ set cpu idle
 set tim y2k
 set rp0 rp06
 at rp0 out/rp0.dsk
+at tu0 m.tap
+set tu debug
+set debug stderr
 b rp0