Found a Useful Modbus HowTo

I have a generic asynchronous protocol monitoring tool I built on a WIN32 Console Application and have used for years. A T connector diode auctioneers the 2 data streams into one COM Port on a PC. It then uses the 3 character delay between polls and responses (which is different for each baud rate) to detect an end of frame at which time it inserts a Time Stamp (TS) and then adds a CRLF to the file and display. The Time Stamp (TS=123.456) is in seconds (3 decimals) since the program was started. It is free to anyone who wants to try it but you will need to build the T connector (drawing provided) that contains the 2 diodes. Send a request to [email protected].