
MATRIX 400™ REFERENCE MANUAL 
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6.2  PASS-THROUGH Pass-through mode allows two or more devices to be connected to a single external serial 
interface. 
Each reader transmits the messages received by the Auxiliary interface onto the Main 
interface. All messages will be passed through this chain to the host. 
When One Shot or Phase Mode operating mode is used, the reader can be activated by an 
External Trigger (for example a pulse from a photoelectric sensor) when the object enters its 
reading zone. 
Applications can be implemented to connect a device such as a hand-held reader to the 
Auxiliary port of the last reader in the chain for manual code reading capability. 
The Main and Auxiliary ports are connected as shown in the figure below: 
Figure 102 – Pass-Through Layout 
Host 
12 
3 3
1
Device#1 
3 
 Main Serial Interface (RS232 only) 
 Auxiliary Serial Interface (RS232) 
 External Trigger (for One Shot or Phase Mode) 
2 1
Device#2 Device#n 
2
Power