There is no easy way. At the moment we have implemented server and client to NIC card.
Communication from client is done with WRAPPER (with server) and communication between NIC (client) and the meter is done using HDLC.
This scenario works best at the moment, but implementation takes time.
At the moment, no. It's possible to create library that can handle small packets but handling large packets is more complex. The problem is if size of PDU is different or if used conformances are different. It can cause scenarios that are not possible to handle.
I can think if there is a way how to just change the HDLC to WRAPPER if PDU size is the same. This is a common problem when we are communicating over the air and communication speed is slow. Using WRAPPER we can save a few bytes.
There is no general, simple solution for this. It depends from the meter. :-(
In general speaking, I would say that wait a while and send HDLC frame again or return the error.
Hi,
Hi,
There is no easy way. At the moment we have implemented server and client to NIC card.
Communication from client is done with WRAPPER (with server) and communication between NIC (client) and the meter is done using HDLC.
This scenario works best at the moment, but implementation takes time.
BR,
Mikko
Thanks for your reply,
Thanks for your reply,
Is there a way to create a hdlc with a pdu pack by use a "dlms c" library?
Hi,
Hi,
At the moment, no. It's possible to create library that can handle small packets but handling large packets is more complex. The problem is if size of PDU is different or if used conformances are different. It can cause scenarios that are not possible to handle.
I can think if there is a way how to just change the HDLC to WRAPPER if PDU size is the same. This is a common problem when we are communicating over the air and communication speed is slow. Using WRAPPER we can save a few bytes.
I can check this at the beginning of next month.
BR,
Mikko
Hi
Hi
I am writing a converter,
What is the proportion of "RNR" and "FRMR" packet in "HDLC" in "WRAPPER" ?
Hi,
Hi,
RNR and FRMR are not used with WRAPPER.
BR,
Mikko
Hi, What to do in this case?
Hi,
What to do in this case?
Hi,
Hi,
There is no general, simple solution for this. It depends from the meter. :-(
In general speaking, I would say that wait a while and send HDLC frame again or return the error.
BR,
Mikko
Hi,
Hi,
Thanks for your tips,
I will do the same.
Hello
Hello
What is the "<ACK>" or "<NACK>" package in the "Wrapper" ?
Do you have a document that I can use ?
Thank you very much.
Mahsen
Hi Mahsen,
Hi Mahsen,
It depends from the message. WRAPPER is documented in IEC 62056-47 COSEM transport layers for IPv4 networks.
BR,
Mikko