changes to README.protocol

diff --git a/cebpic/README.protocol b/cebpic/README.protocol
index 87fb3abe2d4a720eacc464567f67aa1ffbba45db..928fd41ef6f055a6c1ce66c16cebf675614fa821 100644 (file)
--- a/cebpic/README.protocol
+++ b/cebpic/README.protocol
@@ -7,6 +7,9 @@ The first 14 data bits in the NMRA packet should be 1s.
 (i.e. the first two complete bytes should be 11111110 11111110)
 (packets beginning with some other sequence are reserved for non-NMRA messages)
 
+Maximum NMRA message length = 16 bytes (i.e. 112 bits).
+Messages longer than this will cause things to get confused at the moment.
+
 baud rate 9600
 most significant bit first
 8n1