Hi all, today we started working on a first codecentric Plc4x POC using the Siemens S7 driver. Unfortunately we stumbled into a problem that will probably affect other drivers too. In the IsoOnTcpProtocol, I check if the packet starts with the IsoOnTcp magic number and if enough bytes have been read. I was expecting Netty to re-send the buffer, if I don’t consume it. This worked nicely in cases of slow networks. However in case of a fast network, Netty seems to chunk the responses into 512 byte chunks. If I don’t process these, they are not re-sent. Then the next call comes and it doesn’t detect the magic byte at the beginning and then an exception is thrown.
I need to work out how to handle this case (Fast network and responses with a TCP payload greater than 512 bytes) I’m tracking things in PLC4X-76 - When receiving responses with more than 512 byte, the IsoOnTcp protocol doesn't work https://issues.apache.org/jira/browse/PLC4X-76 Think we should double check the other drivers as I’m expecting Netty to behave similarly in other drivers too. Chris
