This is my first attempt at driving a LCD display based on the Hitachi HD44780 LCD controller. The code and circuit wiring is taken from this post on RaspberryPi Spy. I also took some ideas from a similar post on AdaFruit’s Blog.
First go with a HC-SR04 Ultrasonice Range Finder with an Arduino Nano. Very simple, worked out of the box. Connected it up, downloaded the New Ping Library for Arduino, used the example program and off it went.
Below I’ll include the schematic & example program. Will need to have a go at some practical uses for this next.
After 3 versions using a Raspberry Pi, some for something new. Another microprocessor I’ve wanted to play with; the Arduino. Nano in my case.
Back to basics with the resistors only traffic lights. Below are the schematic and sketch.
May have a go at an Arduino powered I2C version next.
Third version of the traffic lights uses a MCP23017 i2c Bus Expander. This project is the gateway to great things as there are so many fantastic i2c devices out there to play with.
Figure 1 shows the prototype on breadboard.
Second version of the traffic lights using transistors.
The circuit diagram & veroboard are shown. Python source code for the traffic light sequence is shown.
Next will be versions of traffic lights using an I2C bus expander.
This post details my first and simplest attempt at driving some LEDs with a Pi. 3 LEDs, 3 resistors and some wires.
The circuit diagram, breadboard version and veroboard version are shown. Python source code for the traffic light sequence is shown.
Next will be versions of traffic lights using transistors and then an I2C bus expander.
There’s a couple of good sources of explanations for the pin-outs of the Raspberry Pi’s GPIO connector.
My favorite being the one on LWK’s Arduino Projects blog. Don’t let the title fool you, the author has seen the light and is tinkering with Pi’s too.
Recently the Raspberry Pi foundation announced Rev 2.0 of the board. I only have Rev 1.0 boards, so don’t need to worry about the pin-out changes just yet. Either way, it is simple enough to make your circuits compatible with both.