Omron CJ1W-DRM21, CS1W-DRM21 Master Remote I/O Communications, Allocations, Master Communications

Master Remote I/O Communications Section 4-1

4-1 Master Remote I/O Communications

Remote I/O communications are used to automatically transfer data between slaves and the CPU Unit without any special programming in the CPU Unit under which the Master Unit is mounted.

Master Communications

CS/CJ-series DeviceNet Unit (master)

CS/CJ-series CPU Unit

Remote I/O communications

DeviceNet

Slaves

Note 1. A CS/CJ-series DeviceNet Unit can function as either a master or slave in remote I/O communications and it can even function as both a master and a slave at the same time. Turn ON the Master Enable Switch (word n, bit

06) in the Software Switches in the words allocated in the CIO Area to set the CS/CJ-series DeviceNet Unit to function as a master. Once this switch is turned ON and master communications are enabled, the Unit will contin- ue to perform master communications regardless of whether the power is turned OFF and back ON again. Turn ON the Master Stop Switch (word n, bit 07) to stop master communications. Master communications are the fo- cus of this section.

2.In the following descriptions, a CS/CJ-series DeviceNet Unit set to function as a master is referred to as a “Master Unit” and a CS/CJ-series DeviceNet Unit set to function as a slave is referred to as a “Slave Unit”.

4-1-1 Allocations

All slaves are allocated words in the I/O memory of the CPU Unit to which the Master Unit is mounted. They are allocated using one of the following meth- ods:

1)Fixed allocations

2)User-set allocations

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