Datalogic Scanning MATRIX 1000 - Manual (Page 28)

Matrix-1000™
18
2
When the auxiliary interface is permanently connected as part of the system cabling,
it is recommended to use the 25-pin connector and connect the cable shield as
shown in Figure 15.
CAUTION
Avoid simultaneous connection to 25-pin and 9-pin signals
of the auxiliary RS232 interface.