diff --git a/dda.c b/dda.c
index a7ec783..7fc6fbd 100644
--- a/dda.c
+++ b/dda.c
@@ -471,6 +471,18 @@ void dda_start(DDA *dda) {
 	current_position.F = dda->endpoint.F;
 }
 
+// step the 'n' axis
+static void do_step(enum axis_e n) {
+  if (n == X)
+    x_step();
+  else if (n == Y)
+    y_step();
+  else if (n == Z)
+    z_step();
+  else if (n == E)
+    e_step();
+}
+
 /*! STEP
 	\param *dda the current move
 
diff --git a/pinio.c b/pinio.c
index 7f22062..e27222b 100644
--- a/pinio.c
+++ b/pinio.c
@@ -42,16 +42,3 @@ void power_off() {
 
 	ps_is_on = 0;
 }
-
-// step the 'n' axis
-void do_step(enum axis_e n) {
-  if (n == X)
-    x_step();
-  else if (n == Y)
-    y_step();
-  else if (n == Z)
-    z_step();
-  else if (n == E)
-    e_step();
-}
-
diff --git a/pinio.h b/pinio.h
index 60b5daa..028fe80 100644
--- a/pinio.h
+++ b/pinio.h
@@ -6,7 +6,6 @@
 #define	_PINIO_H
 
 #include	"config_wrapper.h"
-#include "dda.h"
 
 #ifdef SIMULATOR
   #include "simulator.h"
@@ -34,8 +33,6 @@ inline void power_init(void) {
 void power_on(void);
 void power_off(void);
 
-void do_step(enum axis_e n);
-
 /*
 X Stepper
 */