Host Engineering Forum
General Category => ECOMs and ECOM100s => Topic started by: rub on July 18, 2008, 11:42:24 AM
-
Has anyone connected a Keyence CV3502 vision system to a H2-ECOM100?
The Keyence uses TCP/IP and needs a socket opened from the PLC before it can send anything.
-
Does it use Modbus/TCP?
-
The manual says:
TCP/IP ( no protocol)
UDP ( PLC Link )
Topology: Peer to Peer
Under PLC Link they have Keyence, Mitsubishi, and Omron as supported but not Koyo.
I have tried the PLC Link but could not get a connection.
I also tried the TCP/IP but the keyence system wants a socket opened and I could not get the ECOM100 to do that.
I could only get the ECOM100 to send a UDP packet.
-
Unless your device supports one of the ECOM100 supported protocols, they cannot talk to each other. The protocols your device is "supporting" are actually low level protocols (what's called Data Link Layer, Network Layer, and Session Layer), but not specifying any Application Layer.
Modbus is an Application Layer protocol. The ECOM100 can Master (send) Modbus requests, DirectNET requests, and a Host Internal protocol requests - these are all Application Layer protocols. It supports as a Slave (receiving) Modbus, DirectNet, Host, and K-Sequence requests.
Find out which Application Layer protocols the Keyence Vision System supports.
If the device allows you to write your OWN protocol (e.g. in C), there is a Report By Exception protocol that the ECOM100 can transmit, but you would have to write the software on your Keyence Vision System (is it like a PC?)
-
The Keyence CV-3502 is a stand alone vision system with no way to change or add any drivers. It does connect to a Denso robot controller fine using TCP.
So if I had a TCP to UDP translator would that work?
Do you know of any routers that can translate UDP to TCP?
Thanks
-
Not helpful. UDP and TCP are transport level protocols...not application protocols. Transport protocols are like the character set and application protocols are like languages. If you were to convert Japanese from using their character sets to an English character set transliteration, it would still be Japanese...and most of us still wouldn't speak it. Unless Keyence speaks our language, we can't talk to it.
-
I just want a packet of data to go from one machine to the other. I can translate the data.
The problem as I see it is that the ECOM100 will not send a TCP packet header out and the Keyence does not understand a UDP header.
Is this correct or am I missing something?
Thanks
-
Yes the ECOM100 can send out TCP, in the form of Modbus/TCP. But you are oversimplifying the problem, and understating the importance of the application layer. Unless you are writing the protocol handler itself, you can't simply get a packet and decode it yourself.
-
BobO,
Thanks for the reply. Along with the Keyence vision system I need to talk to a Denso robot controller. The Denso gives you access to the packet. There is no direct memory transfer needed so I just wanted to place my data in the buffer on the PLC side then send it over and decode it on the Denso side.
Is there a place I can get the Modbus spec?
Thanks again.
Fred
-
Fred, you would use RX/WX (or IBoxes ECRX/ECWX), to read/write data to/from the Modbus TCP "slave/server" (with the ECOM100 being the "master/client") using:
- A Modbus TCP peer-to-peer configuration in the ECOM100 using NetEdit
- The map as defined here: http://www.hosteng.com/FAQFiles/ECOM100%20Server%20Client%20Mapping.pdf
You can refer to the ECOM100 manual in the chapter on Modbus TCP for more details as well.