In most cases, this is true. However, with the development of computer and digital circuit technology, the interface capabilities of human-machine interface products are becoming stronger and stronger. In addition to the traditional serial (RS232, RS422/RS485) communication interface, some human-machine interface products already have data interfaces such as network port, parallel port, USB port, etc. They can be connected to industrial control equipment with interfaces such as network port, parallel port, USB port, etc. to realize human-machine interaction of the equipment.
