Unitech MR350MKII manual Communication Subsystem, Point to point mode, Multi-point mode

1.4.Communication Subsystem

The MR350MKII terminal communication subsystem consists of

1)point-to-point connection mode and

2)multi-point connection mode for network processing.

1.4.1.Point to point mode

Either RS-232 or RS-485 port can be used in point-to-point mode when it is set as serial port. Each port can be configured, input data and output data by DOS call. Nevertheless to transfer files, a Kermit server can be invoked by selecting option “3) COM” in user command menu or typing ”COM” in the Ready mode and a Kermit utility should also run on the Host side in order to make the data communication.

1.4.2.Multi-point mode

Either RS-232 or RS-485 port can be also used in multi-point mode by Multi-protocol (define by Unitech) when it is set as Host port. While RS-485 port is assigned to serve multi-point mode, up to 32 terminals can be accessed through one channel, On the other hand, while RS-232 is selected, the number of accessible terminals is limited by the number of available RS-232 ports on the host computer. There is also a multi-point communication protocol built in the MR350MKII for data communication of a multi-point networking.

1.5.Real time clock subsystem

This subsystem allows the program to set and read system date and time of the MR350MKII.

1.6.Relay output and Digital input subsystem

The MR350MKII supports two contact relay ports and four photocoupler input ports for digital signal input/output control, where pin #11/12 and pin #13/14 can also be assigned to RS-232 port and barcode scanner by setting of jumpers J1 to J6 (refer to MR350MKII Technical Reference Manual).

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