Information Technology Blog (Archive)

Previous post: SP Update 1.5 The stackable headers have arrived from E-Gizmo and finally we were able to test Zigbee wireless communication!!! First we followed this tutorial from Sparfkun in assembling the shield. Then we uploaded our sketch to Arduino to send ADC readings of the sensor  to the gateway and computer. We also programmed the XBees to communicate in Star Topology network. Below is the package of our "mote". We have here the sensor, sensor signal amplification ciruit, the stacked Arduino, and XBee shield with the XBee. The tube from the sensor goes to a drum filled with water. To test the circuit, we tried to remove then place water to the drum, observe and take note of the readings. We observed that for every 5cm increase, the ADC readings increase 1 bit. For full testing, we are going to deploy this project on a real river. We have below the gateway which receives the data from the mote. I made a Visual Basic application which sends a string through the serial...

Original circuit from HAMRADIOINDIA. The circuit there uses two temperature sensors and 3 seven segment displays because of decimal point in the output (e.g. 25.6 Celsius). I modified the circuit and simplified it by removing the spare sensor and using only two display. The reason is when I simulated it in Proteus, the output is somehow wrong. I don't know if the output is right on actual but since I want to make sure with the actual circuit, I followed my schematic that gives the right output on simulation. I did not program the microcontroller. The HEX is from the site and the code is available there. Motor circuit from NERDKITS . Great explanation of the basic principle of motors. THERMOMETER:   Digital Thermometer using PIC16F877A microcontroller. The circuit uses LM35 as its temperature sensor, and displays the temperature (0-99 Celsius) using the two 7 segment display.  Input voltage: 9-12V DC then it is regulated to 5V DC connected to...

Previous post: SP Update 1.0 1/16/11 - Finally, the materials have arrived. It was a dream come true for us that finally after so many mishaps that happened, we got our hands on these precious little things. I've submitted the order to Sparkfun.com and a shipping confirmation has been sent from Sparkfun last 1/3/11. We are expecting that it will arrive after 3 days. But 4 days had passed and no news about our package.  Tracking the order, we discovered that it arrived here in the Philippines on 1/06/11. But for some clearance issues, it has been delayed and after 5 days of being delayed, we decided to call FedEx to verify. We have been told that we are going to pay an additional PHP5,000 for the taxes before we can receive our package which is almost 50% of the amount ($276). It was our 2nd time to do online shipping and we did not know about this whole tax thing! It was insane! But because we are so delayed in our project, we have no choice but to pay them the amount to finally ge...