DeviceNet Addressing w/ a SLC & PVW550

Hi Team,

I'm in the process of setting up a system with a SLC5/03 using Devicenet to communicate to (4) Panelveiw 550's and (4) sets of Flex I/O. The thumbnail below shows the configuration.


What I want to do is assign the SLC I/O address ahead of time, but I'm having a bugger of a time determining what they will be. I don't have a system put together to test on so I can not do any commissioning or setup at this time. As you can see from the drawing I assigned node addresses to each element on the network. The scanner module will be in slot 8 (the SLC already exist on a working line and I am augmenting the devicenet equipment to it).

Could someone take a look at this and make some suggestions regarding node assignments (if those I picked are not workable) and help me determine what the SLC I/O addresses will be. Any help will be much appreciated.

Thanks!

DeviceNet data mapping is "wherever you want it to be", so it can be confusing for first-timers. FLEX I/O, especially, has a lot of variables in how much data you configure it to exchange with the master.

Which modules, exactly, do you have connected to each of the FLEX I/O adapters ?

Remember that the 1794-ADN FLEX adapter prepends 16 bits of status data to the I/O connection for module status. After that comes the Input data.

I would, in general, plan to map the PanelView data to the M0/M1 files and access it periodically instead of using precious discrete data table space for it.

Thanks for replying Ken. To the 1794-ADN module I have a 16 point Input module (1794-IB16) and then a 16 point Output module (1794-OB16). Pretty simple.

My goal is to have the addressing similiar from one workstation to another. Have the node address as the only variable. But I can't see where the node address plays into the I/O address. Does it?

Here's the deal; the 1747-SDN has a 32-Word discrete memory table, just like the 1747-SN RIO scanner. It also has 150 words in "M-files" that need to be manually copied into the SLC memory.

However, unlike the 1747-SN RIO scanner, the addresses of slave devices are not in any way related to the location of their data in the memory table.

Instead, RSNetworx for DeviceNet software is used to create the I/O Connections between the scaanner and slaves, and to "map" that data into memory in the SLC.

With just one 16-point Input module and one 16-point Output module, you can easily map them adjacent to one another at the beginning the data table.

Word Zero is reserved for 1747-SDN control and feedback in both the Input and Output data tables.

The 1794-ADN pre-pends one Word of data for FLEX module status.

So if you perform an Auto-Map for just the FLEX I/O, configured for "I/O Only" sizes, your data map will be (where X is the Slot Number)

I:x.0 Scanner Status Word
I:x.1 Node 11 FLEX Status
I:x.2 Node 11 IB16 Data
I:x.3 Node 21 FLEX Status
I:x.4 Node 21 IB16 Data
I:x.5 Node 31 FLEX Status
I:x.6 Node 31 IB16 Data
I:x.7 Node 41 FLEX Status
I:x.8 Node 41 IB16 Data

O:x.0 Scanner Command Word
O:x.1 Node 11 OB16 Data
O:x.2 Node 21 OB16 Data
O:x.3 Node 31 OB16 Data
O:x.4 Node 41 OB16 Data

The data sizes for the FLEX I/O have to be configured within the 1794-ADN by RSNetworx.

Where that data goes once the Connection is made is entirely up to your Data Map that you create in the 1747-SDN. The above is just a simple version, with no room for expansion.

The PanelView data we will put into the M-files... more on that later.

Fantastic! The light has come one! Thank you very much Ken!