Posts tagged ‘RS232’

Building an Auxiliary Display

I wanted to be able to check my web server’s statistics periodically but did not want having to log on ever time when I wanted to do so. The simplest way to achieve this is to have the computer monitor on and run a server statistics program that outputs the information onto the screen. Continue reading ‘Building an Auxiliary Display’ »

An Isolated MOSFET Serial Port Relay Controller

Using DTR (data terminal ready) and RTS (request to send) pins of a PC serial port (RS-232) without actually using the serial data pins, we can interface at least two relay devices with a computer. Windmeadow Labs has an excellent article on how to achieve this using a bipolar transistor (BJT). Here I will show you a similar relay control circuit built using an opto-isolator and a MOSFET. Continue reading ‘An Isolated MOSFET Serial Port Relay Controller’ »