I am using Modbus TCP with the Do-More Simulator tied to ignition. I know that we can read bits from words, but is there notation to read a byte or int out of a uint32?
Not at the driver level. You can do it in Ignition with an expression tag or scripting, though.
Not quite clear where is the uint32, but if you get it with , for example, HRUI1, then HR1 will be one byte, and HR2 the other, if you are looking just for raw values.
HR1 would be a 16-bit value, same with HR2. All registers are 16-bit values and multiple registers are combined to make larger data types but there is no addressing at the driver level to just get one or the other byte from a register.
Ops. I stand corrected. I meant to say one int ( 16 ) but came out byte.
So for byte is as Kevin said, scripting or expression.