Arduino FIO DS18B20 Temperature Logger

We have a Arduino Fio temperature logger, so now maybe we can increase the accuracy by adding an external temperature sensor. I have a couple of DS18B20 Programmable Resolution 1-Wire Digital Thermometers, so I thought, heck, let’s try one out!

These temperature sensors are much more accurate out-of-the-box, so I don’t need to deal with calibration (which I did need to worry about with the internal thermometer). In addition, using separate, discrete components allows for the possibility of putting temperature sensors directly on/in whatever you may want to measure (rather than merely measuring the ambient temperature) and the potential for multiple temperature sensors with a single Arduino Fio (which are available at


Arduino FIO Internal Voltmeter and Thermometer

Let’s extend the low power Ardunio Fio + Xbee setup that I previously blogged about.  I wanted to see if I could create a simple wireless temperature sensor that could allow for long(er) term logging.  Interestingly, the ATmega328P on the Arduino Fio has both a “secret” internal thermometer and internal voltmeter, meaning that I could (potentially) create a wireless sensor with no external additional external components (other than the Fio, XBee, and battery).

So, taking advantage of the available hardware and the code available, I went about creating a wireless temperature logger using an Arduino Fio (available from and two XBees (one for the Fio and one for the coordinator).


Arduino FIO Low Power Setup

As usually, I have been very sporadic in posting new/updated projects due to my prioritization of my doctoral work (i.e., not much time for fun little electronics projects!).  However, I’ve been playing around with the Arduino Fio (available from in my free time for a little while now, so I wanted to post some notes on a very low power usage setup that I was able to put together.

As my free hobby time has dwindled, so has the time I’ve been able to devote to debugging programs written for my little Microchip PICs.  So, given my limited time, I decided to dive right into Arduinos — which utilize a higher-level programming language, making things a little quicker and easier for me to tinker — and try to get some wireless communication working.  After looking through the possibilities, I settled on the Arduino Fio.  The Arduino Fio is a great little Arduino-compatible board that includes a socket for an XBee 802.15.4 wireless module along with a LiPo plug and charger circuit.


PIC18LF2550 Wireless 3-axis Accelerometer

Having a 2.4GHz Serial Link is helpful, but what kind of applications could it be utilized for? Well, I had a number of 1-axis accelerometers from Freescale (graciously provided by their samples department for my electronics lab projects), which I could use detect object orientation. Making the accelerometers wireless would allow for remote sensing of object orientation, which could be applied to virtual reality or possibly augmented cognition. In any case, it allows for some fun experimentation! (more…)

PIC18LF2550 Wireless Servo Controller

I’ve wanted to make a remote control pantilt controller for my wireless camera for some time now. It can be used for remote monitoring, as a webcam, or for color/object tracking. The basis for a pan-tilt configuration is the PIC18LF2550 Wireless Servo Controller, which allows me to control two servos remotely with very little latency (a majority of which is due to the slow response of the hobby servos being used). (more…)

PIC18LF2550 2.4GHz Serial Link

I wanted to make a wireless serial link that would allow me to send and receive data between Microchip PIC microcontrollers and a computer. I found some very useful information and some helpful code for utilizing a Laipac TRW-24G 2.4GHz wireless transceiver with a PIC16F88 as a wireless serial link. The PIC16F88 is a nice little chip that provides a number of useful features (including an onboard USART and the ability to use a bootloader). I am a fan of the PIC16F88; however, I believe that the PIC18 series are much more robust, so I created a circuit that would allow much more flexibility in design and deployment. This project is a relatively simple circuit that utilizes a PIC18LF2550 microcontroller and the Laipac TRW-24G 2.4GHz transceiver to create a wireless serial link. (more…)