Index: firmware/App/Drivers/RotaryValve.c
===================================================================
diff -u -ra811cae0392f1d0f976650ff167945e614b3b854 -r8b819deb3e770c981eed221f63170dd842eedbe3
--- firmware/App/Drivers/RotaryValve.c	(.../RotaryValve.c)	(revision a811cae0392f1d0f976650ff167945e614b3b854)
+++ firmware/App/Drivers/RotaryValve.c	(.../RotaryValve.c)	(revision 8b819deb3e770c981eed221f63170dd842eedbe3)
@@ -138,7 +138,7 @@
 {
     if ( valve < NUM_OF_VALVES )
     {
-        U16 mag8 = ( ( mag % 8 ) < 4 ? ( mag >> 3 ) << 3 : ( ( mag >> 3 ) << 3 ) + 8 );   // round to multiple of 8 to maximize holding torque
+        U16 mag8 = ( ( mag % ROTARY_VALVE_MICROSTEP_FRACTION ) < 4 ? ( mag >> 3 ) << 3 : ( ( mag >> 3 ) << 3 ) + ROTARY_VALVE_MICROSTEP_FRACTION );   // round to multiple of 8 to maximize holding torque
         S16 chgSteps = (S16)mag8 * ( MOTOR_DIR_REVERSE == dir ? -1 : 1 );                 // convert to signed change in position - negative value indicates reverse direction
 
         // log event showing valve position change commanded