diff --git a/README.md b/README.md
index cca919dc6..a2fb1390c 100644
--- a/README.md
+++ b/README.md
@@ -200,12 +200,18 @@ Every telegram sent is echo'd back to Rx, along the same Bus used for all Rx/Tx
 
 ## Ems Plus
 In this chapter we will report our findings on the ems plus.
-### EMS Plus byte layout
+### Message layout
 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
 | - | - | - | - | - | - | - | - |
 | 18 | 00 | FF | 03 | 01 | A5 | 28 | 46|
 |transmitter| receiver | ems plus mark | message type | offset | ? | value | cnc
 
+### Message types
+| Message type | Definition          |
+|--------------|---------------------|
+| 03           | Set temperature     |
+| 00           | Current temperature |
+
 ## The ESP8266 Source Code
 
 `emsuart.cpp` handles the low level UART read and write logic to the bus. You shouldn't need to touch this. All receive commands from the EMS bus are handled asynchronously using a circular buffer via an interrupt. A separate function processes the buffer and extracts the telegrams.