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diff --git a/mware/mean.h b/mware/mean.h
new file mode 100644
index 00000000..893241e2
--- /dev/null
+++ b/mware/mean.h
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+#warning revise me!
+
+
+/**
+ *  DECLARE_SMEAN(temperature, uint8_t, uint16_t);
+ *  for (i = 0; i < TEMP_MEANS; ++i)
+ *    SMEAN_ADD(temperature, adc_get(), TEMP_MEANS);
+ *  printf("mean temperature = %d\n", SMEAN_GET(temperature));
+ */
+
+/**
+ * Instantiate a mean instance
+ */
+#define DECLARE_SMEAN(name, Type, SumType) \
+	struct { \
+		SumType sum; \
+		Type result; \
+		int count; \
+	} name = { 0, 0, 0 }
+
+/**
+ * Insert a new sample into the mean.
+ *
+ * \note \a mean and \a max_samples are evaluated multiple times
+ */
+#define SMEAN_ADD(mean, sample, max_samples) \
+	do { \
+		(mean).sum += (sample); \
+		if ((mean).count++ >= (max_samples)) \
+		{ \
+			(mean).result = (mean).sum / (max_samples); \
+			(mean).sum = 0; \
+			(mean).count = 0; \
+		} \
+	} while (0)
+
+/**
+ * Return current mean value.
+ */
+#define SMEAN_GET(mean)  ((mean).result)
+