diff --git a/avr/devices/c03/defs.asm b/avr/devices/c03/defs.asm
index a7e484b..893aacd 100644
--- a/avr/devices/c03/defs.asm
+++ b/avr/devices/c03/defs.asm
@@ -51,6 +51,15 @@
 
 
 
+; ---------------------------------------------------------------------------
+; EEPROM TLV ids
+
+.equ C03_EEID_SENSOR_CO2  = 0x10
+.equ C03_EEID_SENSOR_TEMP = 0x11
+.equ C03_EEID_SENSOR_HUM  = 0x12
+
+
+
 ; ---------------------------------------------------------------------------
 ; LED module