This assignment, as in input devices is part of my final project (a lux meter). I use my output device board (which is same as input device board) with LCD display, which gives reading of light in autonomous way without need of a computer. Attiny 44 used for implementation of ADC and other calculations and interface with LCD. Design of board and schematic same with input device. Programming add for LCD

Making of board

I designed imput devices board to accommodate also as an output device. Please refer to input devices week to show the design board.

The LCD display

The output device I am using is a 2 lines X 16 digit LCD display. Like this one. Most of them are based on Hitachi HD44780 and have equal pinout.

The LCD has several pins. Most importants are power pins VSS and VDD, and data pins 4,5,6 and 7. If you connect potentiometer to VE you can adjust backlight intensity. Useful for different lighting conditions.

Here you can see LCD attached to input device board also with potentiometer.

Programming

Programming was done using Arduino IDE. We use library for LCD called LiquidCrystal. Instructions for usage of the library are here. Only 4 of the 8 data lines are required to work the LCD.

The code displays a fixed text in row 1 Lux Meter | VA and in line 2 displays a number 0 to 255 which is digital to analog conversion of voltage output of LDR sensor.

For video please refer to Final Project section

Download Design Files

Download schematic files from here
Final code is here: Original code