by Benabadji Noureddine:
This Design Idea demonstrates a new method of driving six LEDs with only two I/O lines from a microcontroller, and so is particularly suitable for any pin-limited chip. It uses a pair of I/O lines combined with a pair of complementary bipolar transistors. More than one LED can appear to be lit by multiplexing.
Two PIC pins drive six LEDs – [Link]
This is a little Tetris game. It is built with a Nokia 5110 cellphone LCD and a Texas Instruments MSP430G2553 microcontroller. The system without the backlight uses less than 1mA. It is written in C with the TI Code Composer Studio.
µTetris with MSP430 – [Link]
The xPico WiFi Shield supports simultaneous wireless LAN client connectivity and access point (AP) functionality. This makes it easy to securely connect to an Arduino microcomputer using web-based tools and interactive applications on smartphones or tablets. Its built-in controller ensures that there is no need for a wireless LAN driver on the Arduino microcontroller to configure wireless connectivity.
The xPico Wi-Fi Shield includes connection management software and a web-based configuration interface to manage connectivity complexity on behalf of the application developer. This significantly cuts down the development overheads for engineers, designers, students and hobbyists who need to quickly add smart Wi-Fi solutions to their Arduino designs.
Lantronix Arduino WiFi Shield – [Link]
This is a dual MCU programmer which supports both AVR and PIC mcu and there is a switch to select between them.
It’s easy to manufacture and have only through hole parts.
Serial AVR and PIC programmer – [Link]
Electronic scales are widely used in kitchens and bathrooms because they can quickly make accurate weight measurements.
A load sensor called a load cell is used for weight measurement. Because the output voltage of this sensor is very small, it is amplified by an operational amplifier (op-amp) and input to an A/D converter. A microcontroller (MCU) converts the signal to weight based on the conversion results of the A/D converter and displays it.
Renesas offers a lineup of microcontroller products for meeting their customers’ needs, such as the RL78/L1x, 78K0/Lx3, and R8C/Lx series with built in LCD driver for designing small and inexpensive models. For highly precise measuring, they offer the 78K0/Lx3, the H8/38086R group, the RX21A group, and other with built-in high precision ΔΣ (delta-sigma) A/D converter.
Renesas MCU for Electronic Scales – [Link]
Andrew @ theresistornetwork.com build a Video streaming board using the STM32 Nucleo board and a Gameduino 2.
I like to check out the thrift stores in my area for one of a kind technical gems to add to my collection. A few years ago I came across a Connectix QuickCam. This is one of the earliest webcams that didn’t require a separate video capture card. Due to how easy it was to install, it was incredibly popular. So much so that Logitech ended up buying Connectix out and forking the product under their own brand.
When I saw it in the store I really had no idea what it was aside from the fact that it was a webcam and it had a parallel port. My first instinct was that a parallel port is simply a collection of TTL lines that I could emulate with a modern microcontroller. I finally had some time to put it into action and decided to stream video frames from the camera to a Gameduino 2 and the FT800 video processor that it uses.
FT800 with Streaming Video on Gameduino 2 – [Link]
by praveen @ circuitstoday.com:
Ultrasonic range finder using 8051 microcontroller has been already published by me in this website. This time it is an ultrasonic range finder using arduino. HC-SR04 ultrasonic range finder module is used as the sensor here. The display consists of a three digit multiplexed seven segment display. This range finder can measure up to 200 cm and has an accuracy of 1cm. There is an option for displaying the distance in inch also. Typical applications of this range finder are parking sensors, obstacle warning system, level controllers, terrain monitoring devices etc. Lets have a look at the HC-SR04 ultrasonic module first.
Ultrasonic range finder using arduino – [Link]
Raj @ embedded-lab.com build a programmable digital timer. He writes:
Digital timer switches are used to control the operation of electrical devices based on a programmed schedule. This project describes a programmable digital timer based on the PIC16F628A microcontroller that can be programmed to schedule the on and off operation of an electrical appliance. The appliance is controlled through a relay switch. This timer switch allows you to set both on and off time. That means, you can program when do you want to turn the device on and for how long you want it to be remained on. The maximum time interval that you can set for on and off operation is 99 hours and 59 minutes. The project provides an interactive user interface using a 16×2 character LCD along with 4 push buttons.
Programmable digital timer switch using a PIC Microcontroller – [Link]
by Kalle Hyvönen:
I bought a small aquarium (54l) as an impulse buy and I needed some lights for it, so naturally I wanted to use LEDs. I also needed a timer for the lights. I also wanted the lights to fade in and out when they were going on or off as a cool effect.
I ordered four Cree XP-G R5 LEDs (cool white, apparently too warm of a light will cause algae growth) and a one amp (switching) constant current supply (with PWM support) from LED-tech.de. I had some Maxim DS3234 real-time clocks with a serial bus (SPI) which looked easy to implement so I decided to use one. I also had one spare Arduino board so that was going to be my microcontroller of choice. I used a laptop power supply as the power source.
LED aquarium lighting with an Arduino based PWM timer – [Link]
Raj @ embedded-lab.com
I2C or IIC (Inter-Integrated Circuit) is a simple bidirectional serial interface, which requires only 2 signal lines for data transfer. It was originally developed by Philips in 1980′s to provide easy on-board communications between a CPU and various peripheral chips in a TV set. Today, it is widely used in varieties of embedded systems to connect many low speed peripherals, such as external EEPROMs, sensors, LCD drivers, port expanders, real-time clocks, etc, to the host microcontroller. In this tutorial, we will explore the chipKIT Wire Library for establishing an I2C communication link between the chipKIT Uno32 board and two I2C sensors. The Uno32 board receives the sensor outputs through the I2C link and displays the results on the serial monitor window on the computer screen.
chipKIT Tutorial 6: Inter-Integrated Circuit (I2C) communication – [Link]