In this tutorial we'll be showing how to utilize a DHT sensor Python library based on C for high-speed GPIO polling to handle bit-banged sensor output. Many low cost sensors have unusual output formats, and in this case, a "Manchester-esque" output that is not SPI, I2C or 1-Wire compatible must be polled continuously by the Pi to decode. Luckily, the C GPIO libraries are fast enough to decode the output.
We carry a few different GPS modules here in the Adafruit shop, but none that satisfied our every desire - that's why we designed this little GPS breakout board. We believe this is the Ultimate GPS module, so we named it that. It's got everything you want and more. This guide will teach you how to wire it up to a computer or an Arduino, and how to use it.
Adding a LCD to any project immediately kicks it up a notch. This tutorial explains how to connect a inexpensive HDD44780 compatible LCD to the raspberry pi using 6 GPIOs. While there are other ways to connect using I2C or the UART this is the most direct method that get right down the bare metal. This technique allows for less expensive LCDs to be used, it does not require any i2c drivers and it won't steal the only serial port on the Pi.
Arduino is a great starting point for electronics, and with a motor shield it can also be a nice tidy platform for robotics and mechatronics. Here is a design for a full-featured motor shield that will be able to power many simple to medium-complexity projects. Build the kit, and learn how to use it with these detailed instructions.
This guide is for our new TTL serial camera module with NTSC video output. These modules are a nice addition to a microcontroller project when you want to take a photo or control a video stream. The modules have a few features built in, such as the ability to change the brightness/saturation/hue of images, auto-contrast and auto-brightness adjustment, and motion detection.
New from the fine people who have brought us the Beagle Board, we now have a smaller, lighter, but powerful single board linux computer, Beagle Bone! We like this move to a more compact and integrated SBC. For example, there is onboard Ethernet and USB host, as well as a USB client interface (a FTDI chip for shell access). It even comes preloaded with Angstrom Linux on the 4 GB microSD card! Here are some tips and tricks to get your BeagleBone up and running.
What's better than a single LED? Lots of LEDs! The matrices use a driver chip that does all the heavy lifting for you: They have a built in clock so they multiplex the display. They use constant-current drivers for ultra-bright, consistent color, 1/16 step display dimming, all via a simple I2C interface. Here is a detailed guide showing you how to solder, wire and control the display.
Thermocouples are best used for measuring temperatures that can go above 100 degC. This is a bare wires bead-probe which can measure air or surface temperatures. Most inexpensive thermocouples have a vinyl covering which can melt at around 200 degC, this one uses a fiberglass braid so it can be used in high temperature measurements such as heaters and ovens. This is a handy guide which covers thermocouple use including an Arduino library and example code.