diff --git a/firmware/osape-smoothieroll-drop-stepper/src/drivers/step_a4950.h b/firmware/osape-smoothieroll-drop-stepper/src/drivers/step_a4950.h
index e5e5a561da588755ab2b58fbeb54423f92c9e45d..5f9dad84cd70bf9aad9383e1d88122ab5b71f709 100644
--- a/firmware/osape-smoothieroll-drop-stepper/src/drivers/step_a4950.h
+++ b/firmware/osape-smoothieroll-drop-stepper/src/drivers/step_a4950.h
@@ -28,12 +28,12 @@ is; no warranty is provided, and users accept all liability.
 // 8: DACs go full width 
 //#define C_SCALE 8 // on init 
 // MICROSTEP_COUNT 
-// 1:   do 1 tick of 256 table, for full resolution 
-// 2:   128 steps 
-// 4:   64 steps 
-// 8:   32 steps 
-// 16:  16 steps 
-// 32:  8 steps 
+// 1:   do 1 tick of 256 table, for full resolution, this is 64 'microsteps'
+// 2:   32 microsteps
+// 4:   16 microsteps
+// 8:   8 microsteps
+// 16:  4 microsteps
+// 32:  full steps 
 #define MICROSTEP_COUNT 1
 
 // AIN1 PB06
diff --git a/firmware/osape-smoothieroll-drop-stepper/src/main.cpp b/firmware/osape-smoothieroll-drop-stepper/src/main.cpp
index 658b290b0b2af1c20f9ca5567a89dddd67178e2c..406ac18e00085669011c996aee1b5e476063771d 100644
--- a/firmware/osape-smoothieroll-drop-stepper/src/main.cpp
+++ b/firmware/osape-smoothieroll-drop-stepper/src/main.cpp
@@ -9,17 +9,20 @@ OSAP* osap = new OSAP("stepper motor drop");
 VPort_UCBus_Drop* vPortUcBusDrop = new VPort_UCBus_Drop();
 
 // clank cz:
-// Z: Bus Drop 5, Axis Pick 2, Invert ?, SPU 1386.6666667
-// TC: Bus Drop 4, 
-// YL: Bus Drop 1, Invert true
-// YR: Bus Drop 2, Invert false
-// X: Bus Drop 3, Invert false
+// AXIS   SPU     INVERT
+// X:     320     false
+// YL:    320     true
+// YR:    320     false
+// Z:     462.2-  false
+// E:     830     currently false, not sure  
+// per bondtech, for BMG on 16 microsteps, do 415: we are 32 microsteps 
+// https://www.bondtech.se/en/customer-service/faq/ 
 
-#define AXIS_PICK 0   // E: 3Z: 2, Y: 1, X: 0
-#define AXIS_INVERT false  // Z: ?, YL: ?, YR: ?, X: ?
-#define SPU 320.0F //1386.6666667F // always posiive! z: 3200, xy: 400, clank-cz: xy: 320
-#define C_SCALE 0.4F // 0-1, floating
-#define TICKS_PER_PACKET 20.0F
+#define AXIS_PICK 2   // E: 3 Z: 2, Y: 1, X: 0
+#define AXIS_INVERT false  
+#define SPU 924.4445F 
+#define C_SCALE 0.6F // 0-1, floating
+#define TICKS_PER_PACKET 25.0F
 
 void setup() {
   ERRLIGHT_SETUP;
diff --git a/firmware/osape-smoothieroll-drop-stepper/src/osape b/firmware/osape-smoothieroll-drop-stepper/src/osape
index 294a5dac3711b23a9cf2386355954c6610c450a3..d5c874d218be169e6b71fa6e57ff3345aaf62246 160000
--- a/firmware/osape-smoothieroll-drop-stepper/src/osape
+++ b/firmware/osape-smoothieroll-drop-stepper/src/osape
@@ -1 +1 @@
-Subproject commit 294a5dac3711b23a9cf2386355954c6610c450a3
+Subproject commit d5c874d218be169e6b71fa6e57ff3345aaf62246