I am developing an industrial sensor using a sensor IC and an ARM MCU which communicate via I2C. The data size is 3 bytes. Because the environment in which the sensor is located is harsh ( high temperature and high humidity ) the sensor has a watertight enclosure, and I can't afford to have more than 1 cable coming out of it.
I want to offer the possibility of connecting the sensor to a PLC, PC and to a custom LCD display at the same time. It doesn't need to be real time. I am considering building a communication module that has an integrated LCD screen and who can pass the data to a PLC and a PC. For the PC communication, I will use USB, but for the PLC, I'm not very sure. What is a common serial protocol that most PLCs have which doesn't an expansion module for the PLC? Thank you.