Tag Archives: Guides

Charlieplexing on the Raspberry Pi

If you suddenly find the need to control many LEDs and do not have the requisite electronics to do so, you can turn to your single board computer, the Raspberry Pi (RBPi) and use it to charlieplex the LEDs. Charlieplexing is named after Charlie Allen, the inventor of the technique. Charlieplexing takes advantage of a feature of the GPIO pins of the RBPi, wherein they can change from outputs to inputs even when the RBPi is running a program. Simply setting a GPIO pin to be low does not allow enough Read more [...]

Dimming LEDs with PWM Generator

nlike incandescent bulbs, dimming Light Emitting Diodes (LEDs) is not an easy task. Incandescent bulbs operate on alternating voltage supply, whereby using Triacs, one can control the effective RMS voltage applied to the bulb. Moreover, since the incandescent bulbs are resistive elements, a simple reduction is voltage is sufficient to reduce the current through it, thereby reducing its light and heat output. LED operation is different, as they work on direct voltage. Each LED requires an optimum Read more [...]

Replacement for Flash Memory

Today flash memories or thumb drives are commonly used as devices that store information even without power—nonvolatile memory. However, physicists and researchers are of the opinion that flash memory is nearing the end of its size and performance limits. Therefore, the computer industry is in search of a replacement for flash memory. For instance, the National Institute of Technology (NIST) conducted research is suggesting resistive random access memory (RRAM) as a worthy successor for the next Read more [...]

Difference between AC, DC, and EC Motors

People have been using different types of motors for ages. Primarily, motors can be broadly classified into AC and DC types, depending on the power source they require to operate. However, the basics of operation remain the same for all types of motors. Current running through a wire generates magnetic fields around it, and if there is another magnetic field present such as from an external magnet, the two interact to generate a mechanical force on the wire capable of moving the wire. This is the Read more [...]

How Do Piezoelectrics Work?

Piezoelectrics, found almost everywhere in modern life, are materials that are able to change mechanical stress to electricity and back again. One can find them in sonars, medical ultrasound, loud speakers, computer hard drives, and in many more places. However popular piezolectrics may be as a technology, very few people truly understand their way of working. At the Simon Fraser University at Canada, and the National Institute of Standards, researchers are working on understanding one of the main Read more [...]

What is PID Control and How Does it Work?

We use control loops all the time. For instance, it is much easier to place an object on a tabletop with your eyes open than it is with the eyes closed. The eyes provide us with visual feedback to control the hand to place the object in the required position on the tabletop without error. In the same way, modern industrial controls regulate processes as a part of a control loop. The user sends a set point request to the controller, which then compares it to a measured feedback. The difference between Read more [...]

Raspberry Pi and Automated Greenhouse

Many people set up greenhouses to grow tropical plants that need plenty of warmth and moisture. Usually these areas are enclosed in steel bracings holding glass/plastic panels that allow sunlight in and prevent moisture from going out. Greenhouse owners control the temperature by opening panels to allow ventilation. In winter, maintaining temperature could be difficult without use of heaters. Manually controlling temperature and humidity could be a tedious task taking away from the actual task of Read more [...]

Cloud Storage and Alternatives

Ordinarily, every computer has some local memory storage capacity. Apart from the Random Access Memory or RAM, computers have either a magnetic hard disk drive (HDD) or a solid-state disk (SSD) to store programs and data even when power is shut off—RAM cannot hold information without power. The disk drive primarily stores the Operating System that runs the computer, other application programs, and the data these programs generate. Typically, such memory is limited and tied to a specific computer, Read more [...]

What is a Wireless Router?

Most of the electronic gadgets we use today are wireless. When they have to connect to the Internet, they do so through a device called a router, which may be a wired or a wireless one. Although wired routers were very common a few years back, wireless routers have overtaken them. Routers, as their name suggests, direct a stream of data from one point to another or to multiple points. Usually, the source of data is the transmitting tower belonging to the broadband dealer. The connection from the Read more [...]

Why do you need a Good Grounding?

Grounding is a safety measure for electrical and electronic systems whereby the user is protected from accidentally coming in contact with electrical hazards. For instance, refrigerators at home usually stand on rubber feet, even when operating from the AC outlet. Although electricity enters the refrigerator and runs through most of the electrical components within it, it has no connection to the outer metal body. Rather, the outer metal body of the refrigerator connects independently to a green Read more [...]