Matrix Orbital 4×20 LCD module

The perfect LCD module for hobby or production

The LCD2041 device is a 4 line X 20 character backlit LCD (Liquid Crystal Display) with an RS232 serial interface.   This LCD module is manufactured by Matrix Orbital and is an excellent choice for hobbyists or professionals seeking a simple display for an embedded device, remote monitoring system or a display terminal.


The LCD is easy to configure and send data to. In addition to the text capabilities, the module also contains a GPIO (General Purpose I/O) port that can be used to drive LEDs or relays.


The following image shows the LCD2041 displaying status information from the Interpeater software:


Protecting the LCD module from static discharge

As with any electronic device, you must be wary of static discharge.  In order to provide a little more protection against static electricity, I covered the back of the module with a layer of anti-static foam.


Powering the LCD module

The LCD is powered by either 5volts or 12volts DC.  It can receive power via pin 9 of the RS-232 connector or via the 4 pin white connector.  The 4 pin connector is the preferred power connection because it guarantees that  you will not accidentally connect the module to a PC with voltage higher than 15volts on pin 9 of the RS-r232 port.  Many RS-232 ports have unregulated DC voltage on several of their pins which can swing widely (from -35v to +35v).

Most desktop PC power supplies contain the required 4 pin connector.  It is white and usually powers 3.5 inch floppy drives or flash card readers.  To use the 4 pin connector from your PC power supply, you will have to rearrange the pins in the connector prior to plugging it into the LCD module.

Sending text to the LCD module

Text can be sent directly to the serial port via a terminal program or software application.  The software provided in the SerialEthernet project contains commands for controlling the LCD2041 from an Ethernet socket.  This allows the LCD2041 to be controlled over a network.

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