Here is another piece of laboratory equipment – LC meter. This type of meter, especially L meter is hard to find in cheap commercial multimeters.
Schematic of this one came from this web page: https://sites.google.com/site/vk3bhr/home/index2-html
It uses PIC microcontroller 16F628A, and because I recently acquired a PIC programmer, I decided to test it with this project. Following the above link you will find the original schematic, PCB, source and HEX files for programing the microcontroller and detailed description.
Simple PIC LC meter - [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]
RGB LED disco light is a simple project designed around PIC16F72 microcontroller.
This firmware is a RGB driver, as name suggests it is used to derive or light red, green and blue LEDs in particular fashion. Its main feature is the pattern shown on LEDs. It is quite difficult to describe pattern in words but we want to specify that first it will derive red then green then blue three times and then a particular pattern is shown on LEDs and again the three LEDs light.
RGB LED Disco Lights - [Link]
Interfacing a cheap phone camera module to a PIC32 microcontroller – [Link]
Here’s an automatic watering system using AVR from Gadgetronicx:
Primitive irrigation systems possess many drawbacks as it fails to conserve water and human energy. So introducing Automation in it can help us to overcome these drawbacks and pave way to conserve water. This can be done with a simple Soil moisture sensor and a Microcontroller, AVR in our case. You can try out this system to automate watering the plants in your home at affordable cost.
Automatic plant watering system using AVR(Atmega16) Microcontroller - [Link]
An app note (PDF!) from Renesas on how to minimize power consumption when sensing switch inputs
A switch input is one of the simplest interfaces to an MCU. However, when very low power designs are needed the pullup or pulldown resistor for the switch can draw a significant current. If the switch input is a momentary switch the current flow is very short so it is rarely significant. However, if the switch input is a door switch or level sensing switch
or any other switch which may remain in the active state for a relatively long time the energy used must be considered
Most of the discussion that follows gives examples for pull-up devices with the switches, the same principles apply for pull-down components. Also all the discussions assume that the EVdd = Vdd (all ports powered from the same supply voltage).
Minimizing power consumption when sensing switch inputs - [Link]
by Matt Richardson @ makezine.com:
Spark has improved and expanded their product line with the Photon wi-fi development board and a pair of new wireless modules for custom circuit boards. The Photon improves on the popular Spark Core microcontroller by adding 802.11n wi-fi connectivity, SoftAP for provisioning, more memory, and a faster ARM Cortex M3 processor. Like the Core, it sits right into a standard breadboard for easy prototyping. And best of all, it can be had for $19.
Photon – A Wi-fi Microcontroller for $19 - [Link]
New „hardwired“ TCP/IP chip from company Wiznet resists attacks, it´s fast and consumes only a minimum energy and host MCU resources.
TCP/IP solutions from company Wiznet are known by its resistance resulting already from their principle . all the solution is hardware-based, thus it´s not possible to change a basic functionality of a device (flooding, spoofing, …). W5500 outstands by its “modesty” – it only requires a few GPIO pins of a host MCU – thanks to a high speed SPI interface (up to 80 MHz) and it also has a very low power consumption. A result of a small consumption is, that the chip heats up to approx. 40´C at a common operation, in contrast to other similar chips, which usually have 60-70´C at operation. This naturally means a higher reliability, possibility of a more dense placing of components and elimination of problems with overheating of a device built-in into a small enclosure.
Energy saving is also enhanced by Power Down and Wake-on-LAN (over UDP) modes. Single 3,3V are enough for power supply, while inputs are 5V tolerant. Status is indicated on LED outputs (full/half duplex, link speed, active) and the chip contains a built-in OS Linux (kernel 2.4.xx, 2.6.xx, 3.1,xx) & RTOS driver.
In our offer can be found the W5500 chip itself W5500-EVB evaluation board, as well as a ready-made module WIZ550S2E-TTL or WIZ550io. Examples of a real usage of Wiznet chips can be found in the document Wiznet application reference.
W5500 will resist hackers attack and save energy - [Link]
Microkite is a DTX module built to utilise the great potential of the new PIC32MX1xx/2xx microcontrollers. It integrates a power supply able to provide power to the external user circuit as well, a microSD connector for data storage and a USB-UART bridge for easy communication with a PC terminal.
The module is intended for inclusion in various control systems and follows the DTX standard pinout which opens the possibility for a trouble-free upgrade with newer models in future. The module fits into a standard PLCC-68 socket and significantly optimises the end user circuit and the later software development process.
Microkite DTX module - [Link]
Use a $4 microcontroller to launch web pages with the push of a button over serial I/O.. by Elliot Williams @ makezine.com:
A microcontroller is a self-contained, but very limited computer — halfway between a computer and a component.
The top reasons to integrate a microcontroller into your projects are connectivity and interactivity, and one easy way to get your microcontroller talking with the outside world is standard asynchronous serial I/O. Many devices can communicate this way, from wi-fi routers to GPS units to your desktop or laptop computer. Getting comfortable with serial I/O makes debugging your AVR programs much easier because the AVR can finally talk to you, opening up a huge opportunity for awesome.
Beyond the Arduino IDE: AVR USART Serial - [Link]