From 001fb8d4322ca32a41edfa91c0a314b56ad01d73 Mon Sep 17 00:00:00 2001
From: rav <ravgit@raav.info>
Date: Fri, 5 May 2017 17:04:27 +0200
Subject: [PATCH] make sure rxRefreshRate > 0

---
 src/main/fc/fc_rc.c   | 6 ++----
 src/main/flight/pid.c | 6 +++---
 2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/src/main/fc/fc_rc.c b/src/main/fc/fc_rc.c
index f4bbb04b2e..2511fcfd5c 100755
--- a/src/main/fc/fc_rc.c
+++ b/src/main/fc/fc_rc.c
@@ -204,7 +204,7 @@ void processRcCommand(void)
                 rxRefreshRate = rxGetRefreshRate();
         }
 
-        if (isRXDataNew) {
+        if (isRXDataNew && rxRefreshRate > 0) {
             rcInterpolationStepCount = rxRefreshRate / targetPidLooptime;
 
             for (int channel=ROLL; channel < interpolationChannels; channel++) {
@@ -227,10 +227,8 @@ void processRcCommand(void)
                 rcCommandInterp[channel] += rcStepSize[channel];
                 rcCommand[channel] = rcCommandInterp[channel];
                 readyToCalculateRateAxisCnt = MAX(channel, FD_YAW); // throttle channel doesn't require rate calculation
-                readyToCalculateRate = true;
             }
-        } else {
-            rcInterpolationStepCount = 0;
+            readyToCalculateRate = true;
         }
     } else {
         rcInterpolationStepCount = 0; // reset factor in case of level modes flip flopping
diff --git a/src/main/flight/pid.c b/src/main/flight/pid.c
index a36832c30a..9b4b7d47ea 100644
--- a/src/main/flight/pid.c
+++ b/src/main/flight/pid.c
@@ -438,14 +438,14 @@ void pidController(const pidProfile_t *pidProfile, const rollAndPitchTrims_t *an
         // -----calculate D component
         if (axis != FD_YAW) {
             // apply filters
-            float gyroRateD = dtermNotchFilterApplyFn(dtermFilterNotch[axis], gyroRate);
-            gyroRateD = dtermLpfApplyFn(dtermFilterLpf[axis], gyroRateD);
+            float gyroRateFiltered = dtermNotchFilterApplyFn(dtermFilterNotch[axis], gyroRate);
+            gyroRateFiltered = dtermLpfApplyFn(dtermFilterLpf[axis], gyroRateFiltered);
 
             float dynC = dtermSetpointWeight;
             if (pidProfile->setpointRelaxRatio < 100) {
                 dynC *= MIN(getRcDeflectionAbs(axis) * relaxFactor, 1.0f);
             }
-            const float rD = dynC * currentPidSetpoint - gyroRateD;    // cr - y
+            const float rD = dynC * currentPidSetpoint - gyroRateFiltered;    // cr - y
             // Divide rate change by dT to get differential (ie dr/dt)
             float delta = (rD - previousRateError[axis]) / dT;