Index: rocdigs/impl/ddx/nmra.c
--- rocdigs/impl/ddx/nmra.c.orig
+++ rocdigs/impl/ddx/nmra.c
@@ -1112,7 +1112,7 @@ int protocol_nmra_sm_direct_cvbyte(obj inst, int cv, i
    int ack = 0;
 
    /* no special error handling, it's job of the clients */
-   if (cv<0 || cv>1024 || value<0 || value>255) return;
+   if (cv<0 || cv>1024 || value<0 || value>255) return 0;
 
    if (!sm_initialized) sm_init();
 
@@ -1333,7 +1333,7 @@ int nmragetcvbyte(obj inst, int cv) {
    TraceOp.trc( __FILE__, TRCLEVEL_MONITOR, __LINE__, 9999, "PT: cvget for %d", cv);
 
    /* no special error handling, it's job of the clients */
-   if (cv<0 || cv>1024) return;
+   if (cv<0 || cv>1024) return 0;
 
    if (!sm_initialized) sm_init();