diff --git a/PDP10/kx10_sys.c b/PDP10/kx10_sys.c
index 7e11df0..04b1609 100644
--- a/PDP10/kx10_sys.c
+++ b/PDP10/kx10_sys.c
@@ -215,7 +215,7 @@ DEVICE *sim_devices[] = {
     NULL
     };
 
-const char *sim_stop_messages[] = {
+const char *sim_stop_messages[SCPE_BASE] = {
     "Unknown error",
     "HALT instruction",
     "Breakpoint",