This computer relays commands from the primary computer

The This computer relays commands from the main computer option in the Multiple Arm Setup dialog box (Edit | Preferences | Multiple Arm Setup) enables the computer to be used with a non-primary arm (Arm2 or higher). In this case, it relays commands from the primary computer. You can choose to connect to the primary computer by defining the proper TCP/IP port and data port.

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Step 5: Setup the Multiple Arm Connection