Hello, could someone kindly assist me in resolving this error?

[Danikha Shyken]

this is the Simulink model

Answer 1

[Fangjun Jiang]

A Simulink model describes a "data flow". It is different than a "code flow", where "voltage_input" is just a variable stored in a memory location. Here in Simulink in a Stateflow chart, "voltage_input" represents an input port. You can't do "voltage_input=voltage_input+1" to change the value of the input port.

You can do "TempValue=voltage_input+1" to resolve it. Think of "voltage_input" represents the actual voltage of a physical input port.

[Danikha Shyken]

I see now. Thanks for your clear and helpful response. It's much appreciated.