Posted September 7, 2014 by Chris

"This time it’s a Logic Pen controlled by a tiny 6-pin PIC10F202. The PCB is 5 cm by 5mm so it fits just fine inside a regular ballpoint pen and have 5 leds (1 power led and 4 controllable from the PIC), over voltage protection on the probe input, reverse polarity protection using a p-fet."

Posted September 5, 2014 by Chris

"To build this tool I’ve used two old CD-ROM writer that lays around in my garage.
The X/Y positioning system it is build using the CD-ROM motor assembly. For the engraving laser I use the CD-ROM writer laser. With this hardware the engraving area are will be almost 38mm x 38mm."

Posted September 3, 2014 by Chris

"This project describes an easy and inexpensive way of adding a digital thermometer and data logging feature to a PC. It involves a PIC microcontroller that gets the surrounding temperature information from the Microchip MCP9701 sensor, and sends it to a PC through an USB-UART interface."

Posted September 2, 2014 by Chris

"Here is a method for making an encoder with two sensors for your application. If you only need speed sensing, you may want to skip down to the construction section. The important variables are the radius of the circle (r), the distance between the two optical sensors (s), and the number of divisions in the wheel (d). …."

Posted September 1, 2014 by Chris

"WireGarden is a simplified way to interact with sensors and other hardware. It is based on the Arduino platform. The WireGarden system has four main parts: Hardware, Arduino Software, Communication and User Software."

Posted August 31, 2014 by Chris

"Not wanting to screw up an expensive complex board by being a first-timer at putting an FPGA into a circuit, I figured I’d build a little test board with the cheapest Spartan 6 you can get (about $10), which comes in a solderable TQFP144 package. Sadly, most high end FPGA’s are BGA and therefore quite hard to solder as a DIY project."

Posted August 30, 2014 by Chris

"Probably the most indispensable tool for making printed circuit boards, is the UV light box. There are a couple of different methods for transferring of a PCB image. The most common homemade method, seems to be the toner transfer method, judging by the number of sites describing it. However, I use the photo lithography method and I have had great results with it so far, so no need to change."

Posted August 29, 2014 by Chris

"Abstract: Measure the temperature with one or more LM35DZ or DS18B20 temperature sensors, and then publishes the result when the value changes or every 20min. There is also a alarm function when the value goes higher/lower than the alarm limits."

Posted August 28, 2014 by Chris

This week, we’re finishing off An Introduction to CPLD and FPGA with Lesson 10: VHDL vs Verilog vs Schematic. Here’s a short overview of the lesson:

"There are many ways to create a CPLD or FPGA image. The most common methods are with VHDL, Verilog or schematic capture. In this lesson we’ll explore and compare all three."

Posted August 26, 2014 by Chris

"The stepper motors are 6 wire unipolar steppers that are controlled by a TI SN754410NE H-Bridge that is connected to a PIC 16fF84 microcontroller. The PIC sends pulses to the H-Bridge that move the motor in 1 degree/step increments in either a clockwise or counter clockwise direction. An infrared detector is used to sense IR pulses sent by the TV remote control."