From a6cfbe8b7f2f56d67f98547c5553ddb840e78736 Mon Sep 17 00:00:00 2001
From: Ferdi Franceschini <ffr@ansto.gov.au>
Date: Sat, 27 Apr 2013 18:16:30 +1000
Subject: [PATCH] SICS-597: Don't drive a motor if it is within precision of
 the target.

---
 motor.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/motor.c b/motor.c
index 57175954..b4452f03 100644
--- a/motor.c
+++ b/motor.c
@@ -689,8 +689,8 @@ static int MotorGetHardPositionImpl(pMotor self, SConnection * pCon,
 /*---------------------------------------------------------------------------*/
 static long MotorRunImpl(void *sulf, SConnection * pCon, float fNew)
 {
-  float fHard;
-  int i, iRet, iCode;
+  float fHard, fCurrHard, fNewHard, fZero;
+  int i, iRet, iCode, iSign;
   char pBueffel[512];
   char pError[132];
   pMotor self;
@@ -709,6 +709,13 @@ static long MotorRunImpl(void *sulf, SConnection * pCon, float fNew)
     SCSetInterrupt(pCon, eAbortBatch);
     return 0;
   }
+  self->pDriver->GetPosition(self->pDriver, &fCurrHard);
+  iSign = ObVal(self->ParArray, SIGN);
+  fZero = ObVal(self->ParArray, SZERO);
+  fNewHard = iSign * (fNew + fZero);
+  if (absf(fCurrHard - fNewHard) <= ObVal(self->ParArray, PREC)) {
+    return OKOK;
+  }
 
   /* check boundaries first */
   iRet = MotorCheckBoundaryImpl(self, fNew, &fHard, pError, 131);