I have some questions regarding IO addressing in the PLC and how data is communicated.
We have some analog and digital points coming in over DH+ RIO (IE8, IE4XOE2, and IB10XOB6 modules).
The analog in and out signals form the IE8 and the IE4XOE2 cards are read / written using MSG block transfers. No module defined tags for addressing the IO directly are created (that I can see).
However while no module defined tags appear (when the module is highlighted in the IO config) I am still able to directly address the point RIO_ADAPTER:I: Data[Group#].Bit.
When these same cards come over EtherNet (or ControlNet) module defined tags are created for the analogs, but none "appear" when I highlight the digital modules. However I am still able to directly address both as mentioned above.
This leaves me wondering:
1) Over DH+, why must I use a block transfer MSG to read my analog data into / from arrays, while I am able to use module defined tags for the digital points? Is this just the nature of DH+, the IO cards, or both?
2) Why do no module defined tags appear in the property window when the IB10XOB6 is selected in either a DH+ or ENet config, but they appear in and are usable from the tag browser?
Thanks
We have some analog and digital points coming in over DH+ RIO (IE8, IE4XOE2, and IB10XOB6 modules).
The analog in and out signals form the IE8 and the IE4XOE2 cards are read / written using MSG block transfers. No module defined tags for addressing the IO directly are created (that I can see).
However while no module defined tags appear (when the module is highlighted in the IO config) I am still able to directly address the point RIO_ADAPTER:I: Data[Group#].Bit.
When these same cards come over EtherNet (or ControlNet) module defined tags are created for the analogs, but none "appear" when I highlight the digital modules. However I am still able to directly address both as mentioned above.
This leaves me wondering:
1) Over DH+, why must I use a block transfer MSG to read my analog data into / from arrays, while I am able to use module defined tags for the digital points? Is this just the nature of DH+, the IO cards, or both?
2) Why do no module defined tags appear in the property window when the IB10XOB6 is selected in either a DH+ or ENet config, but they appear in and are usable from the tag browser?
Thanks
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