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General => Technical support => Topic started by: dan on February 20, 2005, 02:14:48 PM

Title: NMC protocol
Post by: dan on February 20, 2005, 02:14:48 PM

Hi,

I'm planning to use T100MD to controll some slave devices using RS485.
Slaves are only capable to use Networked Modular Control protocol.
There is a NMC protocol implemented?
If not can I use Setprotocol ch,10 to create a protocol?
Do you have an example how to develop a protocol (NMC)?

Problem is that I have no experience in this so I realy need help

Thank you,

Dan

Title: Re:NMC protocol
Post by: support on February 21, 2005, 02:30:28 PM

T100MD+ does not support the NMC protocol that you mentioned. However, to a certain extent you can use the TBASIC language to implement your own protocol since TBASIC allows you to read serial input and write to serial output. If your custom protocol is ASCII based usually it is quite simple to implement.  In fact, we use the TBASIC NETCMD$ to interface to the I-70xx analog module which is a third party product that uses a proprietary ASCII protocol.

For binary protocol, if the error checking is no more complex than CRC16 then you can use the INCOMM and OUTCOMM commands to implement the protocol. An examples can be found at:

 http://www.tri-plc.com/trilogi/modbusFunction04.zip

In the above example the PLC uses the INCOMM and OUTCOMM to implement a MODBUS Function 04 which is not supported by the PLC built-in MODBUS command so we implemented it using TBASIC language.

Title: Re:NMC protocol
Post by: AlbertMartinez on February 24, 2005, 08:28:24 AM

Dan:

If you need additional assistance developing your TRi-PLC Networked Modular Control protocol driver, please let me know.

I provide affordable technical support for PLC-SCADA based system.

Sincerely;

Albert Martinez
almaralbertmartinez@gmail.com
50 La Cruz Avenue
Benicia, CA 94510