Transferring multiple registers from SLC on DH+ to CLX

[TimD]

Hello,

Recently, with great help from the angels on this very forum, I was able to 'talk' with a SLC over DH+ to ControlLogix and pass registers (INTs) back and forth. (this thread: http://www.plctalk.net/qanda/showthread.php?t=58530&page=2)

My question today is, "Can I transfer multiple registers with the same MSG instruction, or use FBL to accomplish the task?"

I have done this very thing using Modbus, Ladder, and MicroLogix, so I am wondering if this scenario can be done in Logix5000. I see in the MSG config that I can specify more than one element to receive, but only one destination tag.

I would just hate to have 100 MSG instructions...

Thanks Again!

 

[OkiePC]

Sure, you can read or write multiple consecutive elements with a single MSG. Just use an array on the ControlLogix end, and make sure the array elements are of the same data type as those in the SLC (INT for INTs, Reals for Floats). Set the number of elements you want to read/write in the MSG setup.

 

[TimD]

Sure, you can read or write multiple consecutive elements with a single MSG. Just use an array on the ControlLogix end, and make sure the array elements are of the same data type as those in the SLC (INT for INTs, Reals for Floats). Set the number of elements you want to read/write in the MSG setup.

Cheers, Okie!

 

[The Plc Kid]

Are you trying to make the clogix control the slc I/O ?

Some of it or all of it?

Or are you just trying to get a few data points from the process the slc is controlling?

If using the clogix as a data concentrator so to speak and just read some data then MSG instructions are fine.

If you are trying to make the clogix control all the slc I/O then using the 1756-DHRIO card in RIO mode with a asb module in the slc processor slot would be a better option.

Which is it?

 

[TimD]

Hi PLC Kid,

I am reading through the SLC program now, It appears I am just transceiving alarm and setpoint data. There might be a couple of interlocks thrown in for good measure. Other than that, the SLC appears to have things under it's own control.

Regards,

Tim

 

[The Plc Kid]

I was checking because some people who want to step forward to clogix but can have their equipment down long enough to rip and replace the i/o or want to keep their i/o investment will use RIO from the contrologix to control SLC or PLC 5 I/O.

 

[TimD]

I was checking because some people who want to step forward to clogix but can have their equipment down long enough to rip and replace the i/o or want to keep their i/o investment will use RIO from the contrologix to control SLC or PLC 5 I/O.

Gotcha,

I see my DH+ card is a DHRIO card in the CLX end, so there's a module to plug into the SLC to make the SLC I/O an extension of the CLX I/O.

I'm glad I don't have to rewrite the SLC, I have 4 weeks to commission (nearly done), I/O loop checkout, Program CLX side, Integrate with SLC side, and Program a FTView HMI... It's insane.