BTW and BTR examples with ControlLogix and Flex IO

[Mo_AB_4EVER 0]

Hi there! We are transferring a RIO network from an Automax PLC to a ControlLogix. The whole network is running good with the old PLC. I can't get the analog blocks to work with ControlLogix. Digital is working fine. I need an example of a working MSG instruction with ControlLogix and Flex I/O Current setup is this: 1756-DHRIO in plc slot 4. In port A, I have 7 1794-ASB flex io scanner, all working ok with digital. In Rack 2, I have 7 flex io modules: Group 0: 1794-OB16 Group 1: 1794-OB16 Group 2: 1794-OB16 Group 3: 1794-IE4XOE2 analog combo Group 4: 1794-IT8 Thermocouple Group 5: 1794-IE4XOE2 analog combo Group 6: 1794-OE4 Anlog out The rack config in the browser is set to Rack 2, Starting group 0, Full Rack (8 I/O groups) Let's try to understand the Thermocouple module: The module config in the browser is set to Group 4, Slot 0. The MSG instruction for BTW is set as following: Message type: Block transfer write, Source element: BTW_R2G4_DATA (a INT global tag), Number of elements: 3. Communications path: RIO, channel 4, Rack 2, Group 4, Slot 0, cached connection. The MSG instruction for BTR is set as following: Message type: Block transfer read, Destination element: BTR_R2G4_DATA (a INT global tag), Number of elements: 11. Communications path: RIO, channel 4, Rack 2, Group 4, Slot 0, cached connection. When I enable de BTR or BTW, I get error 203 codes, communications timeout. I have tried to put array tags for source and destination elements, with no success. Why do I have these comm timeouts if everything digital is working? I have looked in the old software of the old PLC, and the number of data seems to match, i.e. number of elements for read and write. Thanks for your help!

[BobLfoot 302]

I may be repeating the obvious but check out this manual http://literature.rockwellautomation.com/i...um514_-en-p.pdf beginning at page 125. Be sure you've done the following: 1. Added the 1756-DHRIO to your IO Tree in Logix 5000. 2. Added the 1794-ASB to your IO Tree under the 1756-DHRIO in Logix 5000 3. Added a Generic Module as Slot 4 under the 1794-ASB in the IO Tree in Logix 5000 4. Point your BTW and BTR at the Generic Module not the ASB.

[Mo_AB_4EVER 0]

All of this has been done. As mentionned above, all the digital blocks are running fine. I just tried to do the msg ladder code for the group 3 and 4, but all I get is timeouts. :( Does one of you have an working exemple of ladder code with the MSG functions?? Thanks!

[Ken Roach 194]

The RIO Channel, Rack, Group, and Slot values seem correct for a 1794-ASB set up for the most common Single Slot addressing mechanism. There are seven different addressing modes that the 1794-ASB can use, but Standard Single Slot is the most common for 16-point I/O and analog modules. Error 203 is definitely a timeout. An incorrect data size or invalid command block contents would result in a different error code. Timeouts can be physical, but since your digital I/O is working I agree that the timeout is probably logical and related to the Rack, Group, or Slot value. Can you examine and post the DIP switch settings for the 1794-ASB ? It would help to know the Series letter for the 1756-DHRIO and the 1794-ASB as well. If you can post the RSLogix 5000 program as well (at least the Message routine; you could even Export it as a *.L5X), so much the better.

[electric101 0]

this is almost the exact same problem i'm having but with devicenet and only a single 1794 2channel in / 2channel out module. did you get this resolved?