Displaying Characters on an LCD Character Module describes the initialization, displaying of text and creating, down loading and displaying custom characters on our character modules. The code sample is in 8051 assembly language and a program flow chart is also provided. (79k)
Driving a character display from a PC printer port describes a simple method of controlling an LCD character module directly from the parallel printer port of a PC. There is little, if any extra hardware required and the module may even be powered from the PC. (40k)
Graphics Modules
Interfacing to a Graphics Module with a T6963C Controller describes the software and hardware to display an image on any Hantronix graphics module with a built-in T6963C controller. This note includes schematic, flow chart and sample software. The code is in 8051 assembly language. (53k)
Interfacing a 128 x 64 Chip-on-Glass Graphics module describes the set-up, initialization and interfacing of an HDG12864-1 LCD module. It describes the use of the built-in power supply and electronic contrast control. (61k)
Power Supplies for Contrast Adjustment describes circuits for building VDD to VEE power supplies for generating the contrast voltage. These efficient circuits can be used with battery-operated equipment. (41k)
An explanation of LCD Viewing Angle. This is a technical explanation of how viewing angle is specified and how it influences the selection of the right LCD for your application. (46k)
LED Back Light Driving Methods describes several ways of driving an LED back light with emphasis on a technique for obtaining a bright display with minimum drive current. It also describes a method of controlling the brightness of the LED back light. (14k)
Temperature Compensation for LCD Displays. This paper discusses the issues involved in temperature compensation of the LCD operating voltage. A sample circuit to provide this compensation is also discussed. (23k)
Touch Screens
Matrix (digital) Touch Screens. An explanation of this type of touch screen and some suggestions on how to use them. (45k)
Analog Touch Screens An explanation of the theory of operation of 3 versions of this popular type of touch screen with suggestions on controller design. (227k)