Monthly Archives: May 2013


Weekend offer: 30% OFF on 8-digit (double row) SPI 7-segment LED displays

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We are offering 30% OFF (coupon code BDEA254) on SPI7SEGDISP8.56-2R this weekend (May 31 – Jun 2, 2012). SPI7SEGDISP8.56-2R is a MAX7219-based seven segment LED display board with 8-digits which are arranged in two rows of four. The MAX7219 allows you full control of all the digits and decimal points through three I/O pins of a microcontroller. The communication interface is SPI-compatible, and the brightness of the LED segments can be controlled through software. Key Features: 3-wire SPI interface double row of 4-digit displays (0.56″) operates at +5V supply individual control of all digits and decimal points 16 levels of

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Easy Pulse Sensor is now also available from Elecrow

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Easy Pulse, a DIY pulse sensor based on the principle of photoplethysmography, is now also sold by Elecrow, our China-based collaborator, for only $18.50 and ships world-wide through a registered parcel for less than $5. We encourage international buyers to get it from Elecrow because they can save money shipping, and the shipment comes with a tracking number. US customers, however, would still be able to buy it from our Tindie store. If you are not familiar with Easy Pulse, “Easy Pulse is a DIY pulse sensor that can be used for detecting the cardio-vascular pulse wave from a fingertip.

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Making a 8×40 LED matrix marquee using shift registers

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LED matrix displays provide flexibility to display text, graphics, animations, and video, and therefore, they have become a popular mean of displaying information these days. You can see them at gas stations displaying the gas prices, or in the public places displaying information, and alongside highways displaying advertisements on large dot matrix panels. This project is about constructing a mono-color LED matrix display board that consists 320 LEDs arranged in 8 rows and 40 columns. The heart of this project is PIC16F1847 microcontroller which receives data from a PC through a serial port (or USB using an USB-UART interface), and

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Netduino Day 7 – RGB LED color formation using Pulse Width Modulation

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Pulse Width Modulation (PWM) is a digital method of delivering a varying amount of power to a load, and hence can be used to control the brightness of an LED or speed of a DC motor. Controlling the power, we will make this tutorial colorful using a Red Green Blue (RGB) LED. Each segment (lead) of an RGB-LED will get a PWM signal via RgbLed class allowing us to illuminate the RGB-LED with any color defined by RGB. This class can also generate random colors. Using the RgbLed class, some standard colors can also be sent to a RGB-LED.

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