Hello friends! Today we will send data from MATLAB to a serial port. We will begin with one character, then send a line of text entered by the user, and finally look at binary bytes, replies and connection cleanup. These are useful building blocks when a MATLAB calculation needs to communicate with an external instrument or microcontroller. The original tutorial used MATLAB's older serial object. That code remains useful for understanding historical projects, but modern MATLAB code normally uses serialport. We will explain both interfaces clearly so that you do not mix their connection and writing functions in one program. Before connecting any actuator, start with a receiving terminal, a suitable loopback arrangement or a device command whose effect you understand. Seeing a message in MAT ...