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Little Problem
Created Date: March 29,2008
Created By: amos
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I have a dl06 master talking to a dl06 slave using Ibox ecomm100wx.In the to slave destination I enter VC20 at the remote address. When using ecomm protocol in netedit it works just fine. I change the protocol to modbus tcp it times out. I changed vc20 to c20 then it works just fine using both protocols. I was just wondering if this is normal? It was confusing because I couldn't figure why it didn't work using modbus. Entering v40620 in the field also defaults the vc20. Amos
Created Date: March 31,2008
Created by: GKiser
This doesn't make sense. It should work regardless of whether you use ECOM protocol or Modbus TCP protocol. However, perhaps you are looking in the wrong place, because:
V40620 = VC400 (not VC20)
V40601 = VC20
When using ECOM protocol, WX-ing to VC20 actually means write to VC20 in the slave, because the slave is always another ECOM.
However, when using Modbus TCP protocol it is a bit different, but the result should be the same. In Modbus TCP, the ECOM100 translates VC20 into a WX to V40601, but because you have a Peer-to-peer configuration in the ECOM100 for Modbus TCP, it translates this write into Modbus parameters.
40601 (octal) --> 16769 (decimal)
Thus this WX VC20 means a Modbus FC16 (Preset Multiple Registers) to Holding Register 56770 (40001 + 16769).
However, since the slave is also an ECOM100 it translates this FC16 to Holding Register 56770 as a write to VC20.
Thus it should work both ways. Mine does when I experiment with it here.
Greg Kiser
Host Engineering, Inc.
support@hosteng.com
Created Date: April 01,2008
Created by: amos
Thank You Greg for your reply.
I saw my error after I posted but that that wasn't the problem. The real situation was when communicating using Ecomm protocol I was talking to a ECOMM not ECOMM100. When talking modbus Tcp I was talking to a Lantronix UDS10 IAP I just changed the IP Address. Using your example what would the difference be if you would have used c20 instead of vc20?
Thank You, Amos
Created Date: April 01,2008
Created by: GKiser
If you had used a WX C20, then this would get converted to an FC15 (Force Multiple Coils) at Modbus Coil Address of 3089. This is because mapping is listed as:
For WX:
GY0-GY3777 (FC15: Coils 1-2048)
Y0-Y1777 (FC15: Coils 2049-3072)
C0-C3777 (FC15: Coils 3073-5120)
S0-S1777 (FC15: Coils 5121-6144)
T0-T377 (FC15: Coils 6145-6400)
CT0-CT377 (FC15: Coils 6401-6656)
Thus, C20 = FC15: Coil 3089.
Created Date: April 01,2008
Created by: amos
Thanks Greg
I think I can see what the problem was. The address must have been too large for the lantronix to use.
Thanks for the help
Created Date: March 29,2008
Created by: amos
I have a dl06 master talking to a dl06 slave using Ibox ecomm100wx.In the to slave destination I enter VC20 at the remote address. When using ecomm protocol in netedit it works just fine. I change the protocol to modbus tcp it times out. I changed vc20 to c20 then it works just fine using both protocols. I was just wondering if this is normal? It was confusing because I couldn't figure why it didn't work using modbus. Entering v40620 in the field also defaults the vc20.
Amos