Modbus new function

Marco Magnani 7 years ago in Devices / Modbus updated by Tilen Suhadolnik 7 years ago 2


I see that in one of the last BOS version in the ModBus device has been introduced two new configuration settings: Read Function Type and Write Function Type.

I want to understand more how those 2 setting work: which address are written or read  at once instead separately (if I select write or read multi)? This is not clear to me… If we suppose to get only 1 modbus device connected with slave address 1 and it contains many address for eg 10, 11, 13, 20, 21, 25 and 110 (all are coils).  Is the Bos software going to write or read once all the address from 10 to 110? From the time point of view instead? If the read interval (in the BOS  Modbus confi g page) is 100 ms, does  it mean that Bos software will read or write all  the previous address data (10, 11, …, 110) in 100 ms (instead taking 100 ms each as was before)?



Sorry, I wrote read interval but I was refering to command delay: evry 100ms BOS sofware executes the modbus command to read or write the coils


Write function type only changes the function code.

Read function type with multiple read, does read multiple addresses. It can read up to 123 addresses at once.

So, in your example (slave 1 with coil addresses 10, 11, 13, 20, 21, 25 and 110) it should read all those addresses at once. That means it will read those addresses in 100 ms (if that is your command delay and there is nothing else to read).