diff --git a/include/scd4x_data.h b/include/scd4x_data.h
index a3e1bc3..dfeb797 100644
--- a/include/scd4x_data.h
+++ b/include/scd4x_data.h
@@ -3,6 +3,12 @@
 
 #include "nvs_flash.h"
 
+#define SCD4X_NORMAL_MODE 1
+#define SCD4X_LP_MODE 2
+#define SCD4X_SS_MODE 3
+#define SCD4X_OFF_MODE 0
+#define SCD4X_CAPTURE_ENABLED 0b11
+
 struct scd4x_data {
 	uint16_t co2;
 	int32_t temperature;