Modbus RTU - 3.5 chars time [closed]

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I am new in Modbus and developing an application using Modbus RTU. I would like to know how to find out the RTU message frame separation time. In the Modbus RTU specification, It mentions 3.5 chars time, but there is no more data about how i can decide this intervals. Any idea?

Answer 1

It depends on your serial port settings. Based on speed, number of data bits in each character, parity and stop bits, you can calculate time length of 3.5 chars. Calculation is explained here.

Answer 2

Modbus RTU specification also mentions 1.5 character times as maximum silent interval between message bytes. Beyond this, incomplete message is flushed and next byte will be the address of a new message.