In addition to the RS232 serial port, many Matrix Orbital displays have a convenient 2-wire I2C interface that allows a host microcontroller to send commands to the display through only 2 wires. Additionally, the display can also be powered from the microcontroller board through the I2C connector.
For C programming, our 8051 Micro C Development System has a I2C_printf() library function that sends commands to the display through the I2C bus. Usage:
This is very similar to the ANSI C printf function except that the print output goes to the display. An example C program that uses this library function is included in the 8051 Micro C Development System under
\bipom\devtools\MicroC\Examples\8051\tiny\I2C_LCD