   // read one-wire sensors
   oneWireSensors.requestTemperatures();
   sensorData.tempInsideC = oneWireSensors.getTempC(thermometerInside);
+
+  // enable access to sensor data  
+  sensorData.available = true;
  
   update_status(); 
   

#define LOOP_DELAY 0

struct SensorData {
  unsigned int ldr;
  unsigned int hall;
  float tempInsideC;


//------------------------------------------------------------------------------
void interogate_sensors() {

  // block access to sensor data  
  sensorData.available = false;
  
  // read light level
  sensorData.ldr = map(analogRead(APIN_LDR), 0, 1023, 0, 255);
