Devicenet output problem with Ultra3000 drive

Hi all,

Long time lurker, first time poster.

Here's what I'm working with:
-MLX 1500 PLC
-1769-SDN scanner
-(2X) Ultra3000 drives
-RSNetWrx demo
-Ultraware
-RS500

After a bit of head-banging, I have everything ALMOST working. I have the drives in the scan list, I/O sized correctly... PLC can see the inputs from the drives. The only thing I cannot get to work is the outputs to the drives (consumed). I can run the homing and indexes from the Ultraware software, but cannot get the PLC to do the same. When I turn on bits in the PLC I can't see them turn on in Ultraware/RSnetwrx either.

I'm at wits end. I've double checked that I have all my mapping correct, it just seems that the output side of it is missing something!

Would appreciate any and all wisdom. Thanks!

Adam S

Oh, and I have the "logix command mask" set to ones for all the functions I want to use...

I presume you have the 1769-SDN in RUN mode ? You can still get Input data even when the Scanner is idle.

Post the RSNetworx *.DNT file and the RSLogix 500 *.RSS file (zip them up together) and folks might be able to take a look.

Bingo. It was in idle mode. Newbie mistake. What a day...

Ken, just wanted to thank you for all your informative posts. I have worked through many PLC problems (including this first foray into Devicenet) thanks to your many insights posted online.

OK, onto the next step...

Hey Ken (or someone else), could I bother you for one more thing? I'm trying to figure out how to deal with the Feedback Data that comes in on 2 separate words. What's the best way to move this into a long integer? I'm playing around with some masked moves, but I haven't been able to figure out how to get the high bytes into the upper 16 bits of the LINT...

Thanks!

Adam S

You may have to MOVe at least one of the INTs to get the order right, then try a COPy (which will copy the bit pattern bit for bit) with the destination set as your LINT. I haven't used LINTs much, so I am not sure in your controller if the COPy instruction will accept the LINT as a destination.

In most cases, the Length of the COPy instruction is based on the element size of the destination, so in your case a Length of 1 would copy 32 bits beginning with the Source address INT.

I think this is one of the reasons that the Copy Word (CPW) instruction was added to the MicroLogix instruction set.

The CPW is functionally identical to the COP instruction, except it works with datatypes like MicroLogix Function Files and LINT elements.

Hmmm, still not following how to make this happen. Am I interpreting the data fields correctly? This is how I understand it:

1. The "data value low byte" and "data value low middle byte" make up one word in my PLC. I happen to have these mapped to O:1.4

2. The "data value high byte" and "data value high middle byte" make up one word in my PLC. I happen to have these mapped to O:1.5

-> so, these 2 words are the first and second part of a "double integer" (LINT)... O:1.4 is bits 0-15 and O:1.5 is bits 16-31.

--> assuming this is correct, I need to take the upper bits (O:1.5) and move them into a long integer file in bits 16 thru 31, and move O:1.4 into this same integer file in bits 0-15.

Is this correct? If so, I don't see how the COP instruction would know where to map the O:1.5 bits into the long integer... but, then again, I did spend 2 hours banging my head yesterday b/c I forgot to put my scanner into run mode. So, there may be some brain damage, haha.

Thanks for your help.

Hold the phones. I got it working. Didn't realize that it used indexed addressing to accomplish the bit fill. Very cool. Thanks for your help Okie and Ken!