that should do the job

mission/com/VirtualChannel.cpp

@@ -11,14 +11,23 @@ ReturnValue_t VirtualChannel::sendNextTm(const uint8_t* data, size_t size) {
 }
 
 ReturnValue_t VirtualChannel::write(const uint8_t* data, size_t size) {
-  return ptme.writeToVc(vcId, data, size);
+  if (txOn) {
+    return ptme.writeToVc(vcId, data, size);
+  }
+  return returnvalue::OK;
 }
 
 uint8_t VirtualChannel::getVcid() const { return vcId; }
 
 const char* VirtualChannel::getName() const { return vcName.c_str(); }
 
-bool VirtualChannel::isBusy() const { return ptme.isBusy(vcId); }
+bool VirtualChannel::isBusy() const {
+  // Data is discarded, so channel is not busy.
+  if (not txOn) {
+    return false;
+  }
+  return ptme.isBusy(vcId);
+}
 
 void VirtualChannel::cancelTransfer() { ptme.cancelTransfer(vcId); }