Message Sequence Charts added

README.md

@@ -80,7 +80,7 @@ Used to send requested pending message from the gateway.
 
 ## STAT packet
 
-Used to confirm, confirm and inform about pending message, nack the message 
+Used to confirm, confirm and inform about pending message, nack the message
 or inform that there are no pending messages.
 
 ```
@@ -93,6 +93,24 @@ or inform that there are no pending messages.
 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 ```
 
+# Message Sequence Flow Charts
+
+## Time request
+
+![time-request.png](/img/time-request.png)
+
+## Data send (no pending messages)
+
+![data-send-(no-pending-messages).png](/img/data-send-(no-pending-messages).png)
+
+## Data send (pending message)
+
+![data-send-(pending-message).png](/img/data-send-(pending-message).png)
+
+## Check for a pending message
+
+![check-for-a-pending-message.png](/img/check-for-a-pending-message.png)
+
 # Packet type values
 
 ```
@@ -115,4 +133,4 @@ or inform that there are no pending messages.
     ACK_PEND = 0x01,
     NACK     = 0xFF
 }
-```
\ No newline at end of file
+```