Once I’ve got several HQM1286404 graphical LCDs around so I decided to build a prototyping board where I could easily plug LCD to it, read data via ADC and display graphs, plug keypad if needed for some menu functions. Earlier I was testing graphical LCD on prototype breadboard, but dealing with multiple wires (GLCD needs 20 of them) resulted in many failures. It is OK to do simple tasks, but more complex applications require a more stable platform. So here it is: This type of GLCD is standard 128×64 pixel matrix controlled by KS0108 LCD controller. Ones I have comes with smaller non-common pin-header where pins have 2mm step, so I had to draw it for Eagle library which you will find in project files. I decided to make a simple circuit so it could fit in 100x50mm single sided PCB. As base MCU I used Atmega16 which can be replaced with Atmega32 which is pin compatible with Atmega16 have more data memory.