How do you know which hardware serial port ModbusClient uses (e.g., Serial3 on STM32Duino)?

[SeppeBudenaers]

Hi everyone,

I'm working on a project using an STM32 running STM32Duino, and I want to use the ModbusClient library. Is there a way to configure it to use a specific hardware serial port, like Serial3?

I came across this example:

But as far as I can tell, it doesn't let me specify which serial port to use.
Am I missing something, or is there a way to set a different hardware serial?

Thanks in advance!