Output mapping table added

Author: mcmchris

content/hardware/07.opta/opta-family/opta/tutorials/01.user-manual/content.md

@@ -2210,6 +2210,20 @@ The Opta™ Expansions have **8 relay outputs** accessible through terminals pai
 
 ![Opta Digital Expansions outputs](assets/variants-emr-ssr-new.png)
 
+Relay Output terminals are mapped as described in the following table:
+
+| **Opta Digital Expansion Terminal** | **Arduino Pin Mapping** |
+|:-----------------------------------:|:-----------------------:|
+|                 Relay 1                  |            0            |
+|                 Relay 2                  |            1            |
+|                 Relay 3                  |            2            |
+|                 Relay 4                  |            3            |
+|                 Relay 5                  |            4            |
+|                 Relay 6                  |            5            |
+|                 Relay 7                  |            6            |
+|                 Relay 8                  |            7            |
+
+
 The **Ext D1608E (EMR)** variant features 8 electromechanical relays with the following characteristics:
 
 <table>