diff --git a/mkdocs.yml b/mkdocs.yml
index fdf8e80..51193e9 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -171,6 +171,7 @@ nav:
 
   - I/O interface cards: 
       - Revision 4: io-interface-cards/io-interface-rev4.md
+      - Revision 6: io-interface-cards/io-interface-rev6.md
 
 
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