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Solid-State Storage Media in Embedded Apps Jeff uses SD solid-state storage media in embedded designs. In this series of articles， he provides a thorough introduction to SD technology. Read on to learn how he gets real data in and out of the SD card with the FAT file format. My first hard drive was 5 MB and took up only a 5″ bay. Considering double-sided 5″ floppies were 720 KB at the time， that was pretty darn good. Solid-state memory is beginning to give mechanical storage a run for its mo...

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Basic Applications and Safety Precautions How well do you understand solid-state power switching？ In the first part of this series， Steve introduces the method and provides important safety precautions. Use his tips and tricks to work safely with high-power devices. It seems simple enough： just use a microcontroller to turn that widget on or off. Solar power from photovoltaic cells seems to be a current hot interest （both puns intended）， and yet there are many pitfalls along the way，...

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A Guide for Embedded Development FPGAs are becoming increasingly popular in embedded systems. Sharad presents several useful methods for designing a system with FPGAs. He also addresses concerns that come up during FPGA design on a complex board. FPGAs are common in embedded systems. In this article， I will describe effective methods for designing with FPGAs. I will focus on FPGA selection parameters and effective use of resources in high-performance FPGAs. I will also examine issues that crop ...

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Build a Longwave AM Radio Receiver Follow Krzysztof as he constructs a digital direct-conversion receiver for long waves. Tuning is controlled by a USB serial connection with a computer running terminal-emulating software. The LM3S811-based system proves you can build a radio receiver with a few discrete components. I always wanted to build a radio receiver that could be digitally tuned， without knobs or variable capacitors， just a link to a computer. It would be a software-defined radio that ...

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Build a Virtual Instrument Interface The Real Virtual Instrument Interface design controls any musical instrument with a MIDI input and captures its audio output over the Internet. The streaming media device interfaces to virtual music studio software and can also simply record audio if you don‘t need MIDI. During the last decade， computers have become important instruments for musicians. They are used for sound recording， sound generation， and music production. In addition， the all-importa...

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Frequency Reference Synchronization Michael built an accurate frequency reference synchronized to a GPS clock. The frequency counter can count to 50 MHz with 1-Hz accuracy. You can also use it to generate GPS-locked output signals as a frequency reference or as a component in a radio receiver. The device can display GPS information such as time， location， and velocity. An old aphorism goes， "Give a man a clock and he knows what time it is. Give a man two clocks and he is never sure." However，...

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A Tool for Finding and Handling Small Parts It‘s time to take control of your components.You can identify tiny surface-mount parts with a handheld LCR meter. The lightweight tool automatically determines the type of component，inductor， capacitor， or resistor （LCR）， and selects the proper range and signal frequency for the most accurate measurement. The component type， measurement results， and test conditions used to determine the results are displayed on a dot-matrix display. If your wo...

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If you need to design an optimized control loop for a hardware control problem， consider trying a proportional integral derivative （PID） controller. In this article， Robert explains that PID regulations are simple to code， wire， and tune to find the results you‘re looking for. Welcome back to the Darker Side. The vast majority of real-world systems are based around feedback loops， which are used to manipulate the inputs to a system to obtain a desired effect on its outputs in a controlle...

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During bike trips， Ed uses Icom handie-talkies for communication. To keep the radios‘ batteries working， he uses a three-pack charger that he designed at his workbench. The charger has three 250-mA channels and one 100-mA channel so he can charge different packs. An early version of the GPS radio interface described in my October column accompanied us on our summer bicycling vacation （"HT Audio， GPS for APRS， and What Works，" Circuit Cellar 219， 2008）。 I hadn‘t finished the replacemen...

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Tom has often bemoaned that the tools electronic designers rely on haven‘t kept up with the silicon. The answer to his complaint may be Altium's Designer， which allows you to complete an entire design， including hardware and software， from start to finish. When you‘re done， debug with Altium's NanoBoard. Imagine you‘re embarking on a home improvement project-say， a kitchen remodel. Heading over to the local home improvement store you find all of the materials you need. There's finely mil...

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If you are new to programming FPGAs and CPLDs or looking for a new design language，Kareem has the solution for you. In this article， he introduces you to Verilog. Although the hardware description language has been used in the ASIC industry for years， it has all the tools to help you implement complex designs， such as a creating a VGA interface or writing to an Ethernet controller. Programmable logic has been around for well over two decades. Today， due to larger and cheaper devices on the ...

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Beamforming enables you to find problems in your system before they occur. As Martin explains， you can perform your own investigation with a computer， a dual-channel A/D card， a pair of microphones， and some software. Tensions are high and a hostile submarine lurks in the waters just off the coast. A patient exhibits troubling symptoms-do layers of tissue mask a tumor？ A driver checks his mirrors and begins to change lanes but never sees the truck hiding in his blind spot. It‘s better to g...

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A Display for Text, Photos, and Slide Shows Jan‘s electronic ID system is an MCU-based electronic badge that displays color slide shows. Many electronic badges display scrolling text using a matrix of discrete LEDs. This low-power system features a graphical OLED display and can be easily upgraded to handle animation，video， or RF communication. Most of the time， we want to protect and hide our personal identification information. But， every so often，it helps to be easily identified. For in...

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Interface an SD Memory Card with an MCU When it comes to designing an embedded application， memory matters. In this article，Mandar explains how to expand a microcontroller‘s nonvolatile data storage capacity with an SD card. It's an intelligent way to handle the excessive memory requirements of typical embedded applications. In the last couple of years， the Secure Digital （SD） memory card has become a widely-accepted memory solution for a variety of portable devices and equipment， includi...

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Board Layout, Real-Time Animation, and More John designed an expandable platform for light and animation. You can use it to create modular animated signs， animated puzzles， and more. The system features a tray and tiles，which are based on 8 × 8 LED displays. Once the tiles are synchronized， you can pick them up and rearrange them. Every time you turn on a computer screen or look at an animated sign， millions of pixels disappear into your work，your correspondence， or your entertainment. I...

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