Students in Cornell’s ECE4760 produced a variety of microcontroller projects in the last five weeks of the semester. Many use Adafruit products. Projects include real time video spectrograph, circuit plotter, touchpad robot, and a Skittle sorter made of cardboard.
Cornell University Students Design with Microcontrollers - [Link]
This is a quick project for a timer. Recently I finished my UV light exposure box and thought that it will be convenient to have a build in timer to switch off the light after preset time. So I had a PIC16F628A lying around and after searching the web I found a Brazilian site (I think?) with tons of interesting projects with microcontrolers. This project is based on one of them.
The schematic uses the internal oscillator of the microcontroller which is enough accurate for my purposes, but as the pins 15 and 16 are left unoccupied, there can be connected external quartz resonator with better accuracy. As I said, this project is based on an existing project, but actually my schematic is quite different and the code was almost completely rewritten. My programming abilities are little rusty, but I think the final result is quite good.
Simple timer with PIC16F628A - [Link]
by Warren Miller @ digikey.com:
MCUs are used as the main control element in just about every application imaginable. Their power and flexibility make them the go-to component at the heart of most designs. Since it is important to make sure that your design cannot be easily copied, reverse engineered or tampered with, modern MCUs now provide a few different options for protecting your design; a good understanding of the capabilities and trade-offs are important in order to determine which approach is best for a given design.
This article will review some of the common approaches to design protection, such as making your MCU unreadable from the outside world, using on-chip capabilities to validate that the code to be executed is unmodified, and using external components to provide more advanced security capabilities. On-board techniques for tamper detection and possible “penalties” that can be applied also will be described.
Protect Your MCU Design from Copying and Reverse Engineering - [Link]
Build a cheap and simple full software controlled step-up (boost) converter to drive a LED string of 10 LEDs. LEDs are used as string to light up a acrylic engraved plate placed in a holder (also made out 5 layers of lasered black acrylic glas). Step up is from 5V to about 30V, current regulated to about 20mA.
LED step-up converter with ATtiny85 - [Link]
These days I was thinking about a better PIC programmer that can work with Microchip MPLAB IDE software so that I can write my own programs or edit someone else’s programs. I found that there are numerous versions of the famous Microchip PICkit 2 on the web.
Some of them are using the original schematic published by Microchip and some are lite versions – with different parts or simplified schematics. None of them satisfied my requirements. So I got the original schematic, removed the memory chips and the input ICSP connector (which I didn’t plan to use anyway) and made a new single sided PCB. I used mostly SMD parts.
Original PICKIT-2 microcontroller programmer - [Link]
This blog post is about my adventures in implementing a stupidly simple way of transferring data over audio to AVR (and why not other embedded chips too), reaching speeds up to 12kbps with really tiny code and memory footprint, using the internal oscillator of Tiny AVR, with hardware parts that cost next to nothing.
12kbps simple audio data transfer for AVR - [Link]
Limpkin has build a development board for the ESP8266-03:
The ESP8266 modules come with a pre-loaded firmware that will accept some commands through their UART interface (connect to wifi, open udp socket, send data to this IP…). Moreover, since Espressif recently released their SDK you can now load your own custom programs using the existing bootloader. To launch this bootloader you just have to connect some IOs to GND in a specific order.
However, anyone wanting to develop a project involving dozens of Wifi nodes has to start from somewhere, eg make a prototype of their future platform. That is why I developed this development board, so the prototyping stage is as simple as possible.
As you can see in the picture below the dev board breaks out all the ESP8266-03 IOs, includes a 3.3V LDO, a USB to UART converter, some logic and a button to automatically start the bootloader.
A development board for the ESP8266-03 - [Link]
Raj @ embedded-lab.com shared his recent project. It’s a mcu controlled dice based on PIC mcu:
Tons of LED dice projects with different output forms have been published online. The most common output configuration in those projects is a 3-1-3 setup (two rows of three LEDs and one LED at in the middle) of seven LEDs, which simulates the actual patterns of dots found on the six faces of a traditional dice. When it is rolled, one or more LEDs are selectively turned on to display a random number between 1 to 6. This project is about a similar LED dice but with a slightly different output form. It uses 6 LEDs which are arranged in a circular pattern and are labeled 1 through 6. They create a chasing effect when the dice is rolled. The chasing effect slows down gradually, and eventually stops at one of the six LEDs. The rolling is done by a gentle shaking of the dice horizontally. The LED dice is powered with a 3V coin cell battery and uses PIC12LF1822 microcontroller to generate a random number and drive the output LEDs.
MCU running LED dice - [Link]
This project provides some lighting effect by the blinking pattern of the bulbs connected at its output. Up to 8 Bulbs can be connected in between connector CN2 to CN9 and AC power to control them should be connected at Connector CN10. DC Power should be applied at Connector CN11 in accordance with the polarity marked on this connector. Care should be taken while using this it as it contains Main Power on the board.
Microcontroller based running light controller - [Link]