diff --git a/avr/modules/comproto/MESSAGES b/avr/modules/comproto/MESSAGES
index a265eaf..1f1b0dd 100644
--- a/avr/modules/comproto/MESSAGES
+++ b/avr/modules/comproto/MESSAGES
@@ -294,3 +294,22 @@ Offset Length Meaning
 
 
 
+
+DATA Message
+============
+
+Offset Length Meaning
+---------------------------------------------------------
+     0      1 destination address
+     1      1 remaining message length
+---------------------------------------------------------
+     2      1 command code
+     3      1 source address
+---------------------------------------------------------
+     4      2 msg id/ref msg id
+     6      n data bytes
+---------------------------------------------------------
+     6+n    1 CRC8 byte
+
+
+
diff --git a/avr/modules/comproto/defs.asm b/avr/modules/comproto/defs.asm
index 7a4708a..2b27441 100644
--- a/avr/modules/comproto/defs.asm
+++ b/avr/modules/comproto/defs.asm
@@ -52,6 +52,8 @@
 .equ CPRO_CMD_VALUE_SET_ACK          = 102
 .equ CPRO_CMD_VALUE_SET_NACK         = 103
 
+.equ CPRO_CMD_DATA                   = 110
+
 
 ; ---------------------------------------------------------------------------
 ; offsets in CPRO_CMD_VALUE_* messages