Modbus function code 91


I need information about TCP/IP Modbus together with Function code 91 protocol or SEMI E54 communication protocol.
I have already searched on internet but found almost noting.
I need only the read function.
How is the command build-up that is must send to my equipment.
How is build-up the response that I receive back from my equipment.
hopefully you can help me out.

best regards,

You won’t find any ‘standard’ docs on a function 91, because anything about 64 is ‘vendor specific’. Ultimately, the vendor selling the product needs to provide details.