Configuring a Controller
80 372 SPU 780 01EMAN May 2002
‘Ports’ Tab

Overview From this tab in the Controller Configuration window, you configure the controller’s

Modbus and ASCII ports. These settings do not affect the communications setup of

your PC in any way - only the controller’s.

Modbus Ports The following parameters are editable:

Parameter Description
Mode Identifies which data protocol (Remote Terminal Unit or ASCII) to use.
Both the PC and controller must use the same data protocol. Default
is RTU.
If you select ASCII protocol for a port, you can only configure its Parity,
Stop/Data bits, and Baud settings.
Parity Adds a check bit to a packet to make the number of binary ones always
either odd (Odd Parity) or even (Even Parity). If parity is set to None,
the check bit is not added. The PC and controller must use the same
parity. Default is Even.
Stop/Data Sets the number of bits at the end of a packet which prepare the
receiving device for the next packet. The PC and controller must use
the same number of stop bits. Default is 1.
Baud Sets the data transfer speed of the controller’s Modbus port in bits per
second. The PC and controller must be set to the same baud rate.
Default is 9600.
Head Quantum controllers only: sets the slot number on the local drop
backplane where the CPU resides.
Dev Addr Assigns the Modbus address for the port. Default is 1.
Delay Sets the amount of time in tens of milliseconds the controller waits
after receiving a message before sending an acknowledgment.
Default is 1 (10); max. is 20 (200).
Modbus Port 2 Type Momentum M1 controllers only: Sets the port type of Modbus Port 2,
to either RS232 or RS485.