Do It Easy With ScienceProg

You know basics of ARM. Whats next?

You’ve probably noticed that day by day, and more complex hardware gets closer to a user. Of course, I am talking about microcontrollers and processors. Several years ago, it was a challenge to have running Linux on board. Now almost everyone has Raspberry Pi and doing crazy things. As I have noticed, not many hobbyists are building their boards to get things done. There is a wide variety of ready-made developing boards depending on size, speed, price that it looks not worth spending time on what’s already done. Everyone seems to be grabbing Arduino and building amazing projects. In a couple of years, enthusiasts used to crunch ARM projects like cookies. This is thanks to the choice of cheap development boards and improving free software tools. But the most critical role in this is the manufacturers. They finally noticed that the hobby market could be a powerful driving mechanism. Ignoring it means losing the game. Now almost every hardware company is trying to get their development board closer to the maker and hacker community because they like to build stuff and spread the word about it.

Choosing right programmer for AVR microcontrollers

Once you start building something with microcontrollers, one thing you need to take into account is a programming adapter. This is a device that allows uploading compiled code into the chip. I don’t know if this is still fun to build your DIY programming adapter, which is not guaranteed to support all chips, nor will it be safe and reliable. AVR microcontroller niche is one of the most interesting when talking about programmers. If you look at the AVRDUDE configuration file, you will find that there are about 50 of them. Many of them are DIY, while others are official. When I started with microcontrollers, I also was looking for a cheap and easy to build programming adapter. So I have built several if a few years. The first of them was RS232 based programmer that worked with then-popular PonyProg software. Later followed LPT port programmer:

Using current limiting resistors on AVR I/O pins

Today I want to talk about protecting digital Inputs of AVR or any other microcontroller from over-voltages. When you look at most microcontroller circuits found on the internet shared by hobbyists, you don’t find any input protection. Some argue that this is not needed or don’t understand in most cases how it works. Let’s see how a simple resistor can save the day. Lets see at simplified version of digital input of AVR microcontroller. We can see there that input uses CMOS logic where the transistor is switched by voltage. According to the AVR datasheet, the gate control voltage should stay within the -0.5V to VCC+0.5V range. If we power our device with a 5V supply, we need to ensure that the pin input voltage stays in the range of -0.5 to 5.5V. When the input voltage source is taken from the same power supply, we don’t have to worry much about it. But what if AVR is accepting digital signals from other sources like sensors, other devices powered by their power supplies. Can we be sure that voltage will always be within safe limits? This is why there are two clamping diodes (sometimes called ESD protection diodes) used. They…

Networking with Cisco and certification

Probably many of you have heard about Cisco Systems. It is a large corporation based in America, California. It primarily designs and manufactures networking equipment. Linksys routers are one of the well-known brands. They are known for their great performance, flexibility, and reliability. No doubt Cisco does its job great in this sector. But Cisco is known for a wider variety of products and services. Besides basic consumer routers, they produce other network equipment like VPN, network storage, VOIP conferencing systems. Ccie routing and switching are simple and versatile, which is suitable for any business and computing.

The best solution in Atlanta to all my data recovery problems

When you remain stuck in late evening Atlanta traffic after a delayed flight holding you back at an alien city airport for a good part of a day, there’s hardly anything that can seemingly go wrong! I lived through all these irritations upon my return to Atlanta last month, only to realize that humans can never have enough patience to deal with the vagaries of life. I had rather excitedly plugged in my portable hard drive into my laptop to watch a movie, only to see nothing happening to the computer! My little ten-year-old daughter came running up to me to tell me how the drive had stopped working a few days back. Gosh – there was a terrible expense staring me right in the eye. It didn’t take me long to recollect memories of how I’d ended up paying four times the price of the hard drive the last time my little kid had dropped it off from the computer table. Not sure if the guys at the data recovery lab were rubbing it in when they told me that I’d damaged data clusters by trying to screw-drive my way through the hard drive case. The data that the…

Bit Band operations with ARM Cortex microcontrollers

I got few questions from our readers about the bit-band feature in ARM Cortex microcontrollers. It may seem to be a prominent topic, still may lead to come confusion while using bit-banding. So let’s look at this feature a little bit closer. Why use bit band? Simply speaking Bit banding method allows performing atomic bitwise operations to memory areas. Why use bit banding? The most straightforward answer is because ARM Cortex doesn’t have something like BIT CSET or BIT CLEAR commands like most of the 8-bit microcontrollers do. So this is somewhat a workaround solution. Another question may rise – Why not using the read-modify-write method? Again this method is not reliable in some cases. For instance, f there is an interrupt during this operation; it can cause data corruption. Other situation may occur in embedded OS when different tasks may modify the same memory location. So we want a method that allows setting or clear individual bits with a single instruction. This is where the bit band method helps.

Electret condenser microphone amplifier for use in microcontroller projects

Most microcontrollers have ADC input, which can sample an analog signal, including sound. Even using Arduino, you can do many cool projects using audio information. For instance, you can make a voice-controlled device such as Audio Recorder, voice-activated switch, and more exciting audio-related projects. In this post, I want to focus a bit on the microphone part – the circuit required between the electret condenser microphone and MCU ADC input. Generally speaking, you cannot connect the electret microphone directly to the ADC pin and expect it to work. The part needed here is called an electret condenser microphone amplifier circuit. Electret microphone with preamplifier stage Condenser microphones require power from a battery or external source. The resulting audio signal is a stronger signal comparing to a dynamic microphone. First of all, the electret microphone isn’t only a condenser inside. It already has a preamplifier inside usually made of FET transistor, which is connected in common source configuration: First, the electret microphone needs to be powered through the drain pull-up resistor. Its value depends on the power supply voltage. The rule of thumb is to add 1kΩ per +1V of the power supply. Up to 10V 10kΩ resistor will work fine.

Working with SQLite in Raspberry Pi using Python 3

Last time we did a few basic operations with SQLite in Raspberry Pi. We learned how to set up SQLite3, create the first database file and fill it with data. Using SQL commands, we were able to select data and print it on the terminal screen. But eventually, you will face more complex queries or store data automatically so other routines could read it. For instance, you will build a simple project that would read data from the digital temperature sensor. One of the great ways of storing data into a database is to use a python script. Anyway, you are probably going to use it for GPIO operations. So let us learn how to store simple data to SQLite database using python.

How an Online School Assists In Integrative Science Learning

Letting students participate in science competitions has always been a good way to promote learning. And some institutes have taken the contemporary notion of competition to the next level by bringing in initiatives such as the International Genetically Engineered Machines (iGEM) competition. This year, the version had many projects related to synthetic biology; the concept at this level is to design, build and test genetically engineered organisms. A lot of these have a direct link to biomedical engineering. For instance, one project focused on engineering gene circuits in a model organism of yeast to better understand how cells make their decisions. These circuits may very well be used in future bio-manufacturing. Projects such as these fall in integrative science and students can be reared for such learning through online education. Not only are there a massive number of tools, but hands-on tutorials can also serve as a good guiding template for the student.

Getting Your Kids Excited To Learn From A Science, Engineering or Math Tutor

Did you see the new Goldie Blox video? This company, whose tagline is “toys for future engineers,” just released a viral video in which three young girl engineers execute a Rube Goldberg machine set to the tune of the Beastie Boys’ “Girls.” This video is excellent because it helps draw young girls’ attention to the possibilities of engineering. Maybe after seeing the video, they’ll ask their parents for a Goldie Blox kit or try to build a Rube Goldberg machine in their living room. Maybe they’ll learn, as all engineers do, that a successful project means educating yourself in math and physics; that you need to know exactly how far apart to place each domino to make sure your train falls at an even, consistent rate.