diff -r 6eafc4c2bf3d -r c6bbd1380f22 main/config.h
--- a/main/config.h	Wed Oct 09 22:51:37 2019 +0200
+++ b/main/config.h	Fri Oct 11 13:12:34 2019 +0200
@@ -178,8 +178,14 @@
     uint32_t		pressure_zero;			///< Zero offset in mV.
     uint32_t		pressure;			///< Pressure in bar * 1000;
     int			mode;				///< Unit mode
+    uint32_t		alarm;				///< Alarm bits
 } unit_t;
 
+#define ALARM_UNIT_PRESSURE		0x0001		///< Unit pressure sensor error
+#define ALARM_UNIT_TEMPERATURE		0x0002		///< Unit temperature sensor error
+#define	ALARM_SYS_TEMPERATURE		0x0004		///< System temperature sensor error
+
+
 /**
  * @brief Write units to disk.
  */