diff --git a/s7plcFW.html b/s7plcFW.html
index 49f8748..83db703 100644
--- a/s7plcFW.html
+++ b/s7plcFW.html
@@ -54,6 +54,7 @@ Besides the
  <li>new communication protocol (FETCH/WRITE)</li>
  <li>the modified <code>s7plcFWConfigure</code> function</li>
  <li>additional support for write-connection-status (see <a href="#stat"> <code>"s7plcFW&nbsp;stat2"</code> </a>)</li>
+ <li>when using bi and bo bits 0-7 and 8-15 are swapped (i.e. for bit 3 use 3+8=11, or for bit 13 use 13-8=5)</li>
 </ol>
 there should be no other differences.
 <br><br>