I have an obsolete hardware Tank Radar Level Transmitter that communicate with mcu using custom protocol (it appear to be similar to modbus RTU), that hardware comes along with an old commissioning software that works perfectly fine under latest windows, that software contain all communication protocol components that I try to extract and use in something like Arduino to pull data out of radar, anyone can help out?

CodePudding user response：

The best tool to analyze a protocol is Wireshark. Run it on the communication link between the Windows machine and the radar. First possibility: the protocol is actually something that Wireshark knows (some trials and errors with the "Decode as" menu may be necessary.) Second possibility, less funny: the protocol is indeed completely proprietary and unknown to Wireshark. At least, Wireshark will make it easier to examine the binary data.

CodePudding user response：

What you need is called a sniffer. Use that as a keyword and you should be able to find plenty of info here at SO and around the web.

To set the record straight it is actually possible to use Wireshark to sniff on Modbus RTU over serial, see my answer here. If your protocol is similar to Modbus I would start with SerialPCAP.

If you prefer more Windows-friendly solutions you can check these out: 1, 2.

Since Modbus is pretty simple I would say reverse engineering a similar protocol should be, maybe not a piece of cake but just manageable, even if you are not very experienced.

These days when almost everyone is a maker or at least a wannabe, you might want to first take a good look around, maybe somebody else already reverse-engineered that protocol and published it somewhere.