How to connect to legacy Yokogawa products using Ethernet protocol

All messages sent to the WT3000 must be encoded. The encoding method is as follows:

Since there is no way to indicate the end of data in Socket communication, every message constitutes a packet with a 1-bit header indicating the last message and a 31-bit header indicating the message length at the beginning. The message length header is in network byte order. For example, if the password is empty, you need to send 0x80 0x00 0x00 0x00 as the result of the encoded empty string. For binary block data, the entire block data is encoded and transmitted in this way.

You also need to follow the steps to receive a message (including an empty string) from the server. Please take a look at the Python script attached.

You can use a packet sniffer such as wireshark to capture the packets with header information while the instrument is connecting to a compatible Yokogawa software.