Omron RECV Command

[Jay Anthony]

Why does it give the status for Node 1 as 'No reply from Node 1' when I transfer the setup from Node1 PLC? I get the 'Successfully completed' status for both nodes when I transfer from node 2.

Thinking. Wait a minute.

am thinking that I am doing something wrong in the routing tables. But its just selecting the SIOU unit number, giving it a network number and transferring it to the PLC. What am I doing wrong???

Are you using two seperate network numbers or just one? PLease post routing table screenshots (use table view) for both PLCs. Also please tell how you are connected to the PLC. By Ethernet? By serial? By Toolbus?

 

[automatic]

I am just using one network number. I am connected to the PLC from my laptop using Toolbus. The two PLCs and the laptop are also plugged into a switch and can ping each other. Here's the screen shot of the routing table and the ETN setup. They are identical for both PLCs.
PLC1 is node 1 and Unit no. 1 and PLC 2 has node 2 and unit no. 1.

 

[Jay Anthony]

PLC1 is node 1 and Unit no. 1 and PLC 2 has node 2 and unit no. 1.

Just to clarify as I try to figure this one out:
The routing tables both have network 1 and are identical? This would be correct but you keep talking abount node numbers when we are talking about routing tables.
Please also clarify for me the node number switch settings on the front of each ETN module.

 

[Jay Anthony]

@MOV(021) #0001 D5 (Number of reception words:1)
@MOV(021) &244 D6 (Source network number. The IP address xx.xx.244.xx)
@MOV(021) #0101 D7 (Source node number: 01, source unit address:01)
@MOV(021) #0705 D8 (Response reqd., port no. 7, retries:5)
@MOV(021) #0000 D9 (Response monitor time = default)
@RECV(098) A600 2000 D5 (Recv A600 at CIO 2000)
)

"@MOV(021) #0101 D7 (Source node number: 01, source unit address:01)
If you are still using this MOV statement, there is a problem with it also:
The source unit address is 00 for the CPU. By specifying 01, you are trying to directly address the CPU BUS UNIT 01 (I know this is the Ethernet but the data you are trying to receive is in the CPU!) Also for a RECV instruction, the source node number is the remote PLC, not the one that executes the instruction.
So if you are trying to RECV one word from PLC1 into PLC2 the source node is 1.
If you are trying to RECV one word from PLC2 into PLC1 the source node is 2.
Therefore the MOV instruction in PLC2 should read as follows:
"@MOV(021) #0100 D7 (Source node number: 01, source unit address:00)" for a RCV instruction from PLC1 to PLC2.

 

[automatic]

Just to clarify as I try to figure this one out:
The routing tables both have network 1 and are identical? This would be correct but you keep talking abount node numbers when we are talking about routing tables.
Please also clarify for me the node number switch settings on the front of each ETN module.

Node number switch setting for PLC1: 01 (0 for 16^1, 1 for 16^0)
Node number switch setting for PLC2: 02 (0 for 16^1, 2 for 16^2)

I just mentioned about the node number settings because I included the setup image also.

Thanks!

 

[automatic]

"@MOV(021) #0101 D7 (Source node number: 01, source unit address:01)
If you are still using this MOV statement, there is a problem with it also:
The source unit address is 00 for the CPU. By specifying 01, you are trying to directly address the CPU BUS UNIT 01 (I know this is the Ethernet but the data you are trying to receive is in the CPU!) Also for a RECV instruction, the source node number is the remote PLC, not the one that executes the instruction.
So if you are trying to RECV one word from PLC1 into PLC2 the source node is 1.
If you are trying to RECV one word from PLC2 into PLC1 the source node is 2.
Therefore the MOV instruction in PLC2 should read as follows:
"@MOV(021) #0100 D7 (Source node number: 01, source unit address:00)" for a RCV instruction from PLC1 to PLC2.

Jay, I am eternally grateful to you for saving my weekend! That worked. I rebooted the PLCs and tried them many times just to make sure that I am not having an illusion. I had to address the unit number of the CPU and not the Ethernet unit.
Just curious, what happens if I set the unit number of the Ethernet unit to 0? Is there a way to re-assign the unit number of the CPU?

 

[Jay Anthony]

Just curious, what happens if I set the unit number of the Ethernet unit to 0? Is there a way to re-assign the unit number of the CPU?

No, the unit number for the CPU is always Unit #00. I didn't want to confuse you during your struggles but the address of the CPU BUS UNIT is Unit number + 16 (&H10). Therefore CPU BUS UNIT #00 would be #10 and CPU BUS UNIT #10 would be #1A.

Well, I guess I scared you when I didn't come back for two hours. I thought you went to bed. You must be working to a weekend deadline.
Just curious, send me a PM or email and tell me where you are working. See my profile.

 

[jimmy.wong]

I surmise that you have not set up a routing table in both PLCS that defines an Omron FINS network number for the Ethernet module in each PLC.

Also tell us more about the IP address and the subnet mask that you have assigned for the Ethernet network. If the node number in your IP address is higher than 127, you will need a FINS to IP network translation table.

Hi Jay, can you explain detail for "If the node number in your IP address is higher than 127" ? I don't get it. Currently I have a project to receive data from a omron PLC but facing problem.