diff --git a/firmware/stepper-drop/src/main.cpp b/firmware/stepper-drop/src/main.cpp
index fb1e22c4afecc9af4505a4d1cdd53d473ab1ae40..9653f53d543090a3451f94527fe732c187979f39 100644
--- a/firmware/stepper-drop/src/main.cpp
+++ b/firmware/stepper-drop/src/main.cpp
@@ -108,6 +108,7 @@ void setup() {
   homeSetup(&homeStateEp);
   // links... 
   vpUSBSer.begin();
+  vb_ucBusDrop_setup(&vb_ucBusDrop, true, 0);
   // stepper init 
   stepper_hw->init(false, 0.0F);
 }
diff --git a/firmware/stepper-drop/src/osape_ucbus b/firmware/stepper-drop/src/osape_ucbus
index 994f7626eecf15d7db38949b309e2551411abe0d..ef4a8fe33c71eedbe7b76ef7c9cc5a9de3017852 160000
--- a/firmware/stepper-drop/src/osape_ucbus
+++ b/firmware/stepper-drop/src/osape_ucbus
@@ -1 +1 @@
-Subproject commit 994f7626eecf15d7db38949b309e2551411abe0d
+Subproject commit ef4a8fe33c71eedbe7b76ef7c9cc5a9de3017852