It’s an example of PC Serial RS232 Port interface To 8051 microcontroller.
It is an example of interfacing Serial RS232 port to 8051 microcontroller. This example show that how can we configure and use serial channel of 8051 microcontroller for sending and receiving data to other device like PC. In so many projects we need to share data or information to other devices. We can provide control between PC and other devices. After acquiring data from embedded device PC software can perform so many other processes to make this data useful information. For example we can read status of sensors using microcontroller and can control other part of our machinery. It is also possible to provide remote data acquisition and control in this way. Data can be read and be reported to a remote location using web & network. There may be several other possibilities.
This is a simple RS232 port interfacing example in which we are controlling 8 LEDs through PC serial port. A software like hyper-terminal can be used to send data to microcontroller. 8 LEDs can be replaced by transistors & relay switches to control and operate high volt devices.
For basic operation & components used in an 8051 based microcontroller based systems see
8051 Basic LED Flasher.