Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs
Turn-key PCB assembly services in prototype quantities or low-volume to mid-volume production runs

Prototype PCBs fast

Making PCB at home is time consuming matter. How to make prototype PCB fast at home require some skills. I bet fastest and messiest thing would be using resist-pen and paint track directly on PCB board. But this process is limited by complexity of your circuit. More complex your circuit is – more mistakes you can make. It is better to manage one good PCB layout software like CadSoft. This is more than enough for hobby projects. For smaller PCB’s you don’t even have to buy it. It has free limited version where PCB size is limited to 2.5×4”. It is rich in component libraries o make prototyping PCB even faster. For prototyping you will need etchant solution (like Fe2CL3), laser printer, iron, glossy photo paper and copper board. And start prototype PCBs fast: First step – draw your schematic to schematic capture program. Then place parts on the board and route the board; Print trace image in a glossy paper; Transfer toner to PCB using hot Iron; After paper stuck to PCB soak it with water and remove; Etch the board; Clean toner from PCB; Drill holes; Now you are ready to solder. Find mode details on prototype PCBs…

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Programming and customizing AVR microcontrollers

AVR microcontroller programmes can be classified by programming method – how to program is loaded into microcontroller from the computer. One is Parallel programmer (byte by byte). This isn’t a popular programming method. But it is a fast programming method. Using a parallel programmer you can set fuses which will protect from using ISP method. But the main disadvantage of parallel programming is that you have to remove microcontroller from the circuit. This might be used when producing a series of the same kind preprogrammed microcontrollers before they are soldered into the board. The parallel programmer can program RESET pin to be used as fully functional I/O line; this is why ISP cannot be used after this procedure. Restoring of RESET function can only be done with Parallel programmer. The serial programming interface is more convenient for electronics hobbyist. The main benefit of the ISP programmer that you can program microcontroller directly on board. ISP programmers can be connected to COM or LPT port. COM port is becoming obsolete as it requires additional circuitry, while LPT programmer can be as simple as few wires connecting AVR to LPT port. Popular ISP adapters: https://elm-chan.org/works/avrx/avrx_com.png. Simplified and Buffered. https://www.lancos.com/e2p/avrisp-stk200.gif. Most popular AVR-ISP…

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Embedded C program libraries and linking

What is compilation of program maybe it is more or less clear. But what is program linking? I am sure many beginners heard of this but done exactly know what it is. In a few words I can say, that linker creates an output file from relocatable objects. Compiler is not one big program. It usually consist of up to a dozen smaller programs. These programs are controlled by some program so called “program driver”. This driver can be a makefile and make.exe program. The pieces of whole compiler are: the preprocessor, the syntactic and semantic checker, code generator, the assembler, the optimizer, the linker and make program. Lets see common example of compiling procedure: These programs are split in pieces for easier design and maintain as each is specialized program in its own. In many cases same program can be used for different programming languages. One disadvantage of running different tools will take longer time that running one bigger program. Because there is need to send information between programs. There can be two types of libraries that can be linked to program: static and dynamic. If a copy of libraries is physically part of executable, then we say program…

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JTAG Solutions for Testing-Programming

In a few words JTAG is debugging system of embedded systems. But sometimes it is used to program as it allows doing this. JTAG debugging is supported by AVRStudio with JTAG Solutions for Testing-Programming like JTAG-ICE, JTAG-ICE MKII, Dragon, etc. JTAG is understanded as tool which allows to manipulate and track the status of supported AVR while microcontroller is running on a circuit. JTAG allows to stop execution at any time, manipulate internal registers. It allows to examine Flash memory, EEPROM memory, SRAM memory, register file, Program counter, fuse and lock bits and I/O of course. JTAG debugging is working on Atmega microcontroller series starting from Atmega16. What you can get when using JTAG with AVRStudio: Emulation of analog and digital; JTAG Programming support; Support of ASM and high level language like GCC; Program and data bits Breakpoints; Real time operations One of simple JTAG Solutions for Testing-Programming adapters (AVR-JTAG) can be found at Olimex which is fully assembled and tested.

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Sensing Sound Wave with microcontroller

Sound wave can be sensed by using sound sensor. If you are designing some kind of robot, sometimes it is useful to enable sensing of sound. Then you can program your robot to follow your voice commands. In some cases sound wave sensors are used as collision sensors. Sound wave sensor is a microphone. Microphone is a device which converts sound pressure in to electric signals. Lets see how sound wave can be sensed. As we already know, sound is a complex signal which consists of multiple different frequency waves. One sound wave can be represented as sin or cos signal: When many of such waves are summed (s called harmonics), we can represent any analog signal- any shape and any frequency. X(t)=A*sin(2πt/T)=A*sin(2πft), Where A – Amplitude, T – Period, f=1/T – frequency, t- time. This is a function of above sine signal. I am not going too deep in to details of trigonometric functions, you can find them in many math or physics book. Lets see how square impulses can be made of few different frequency, phase and amplitude sine waves. We can see in illustration that by adding multiple harmonics we can get desired signals. More harmonics we…

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IrDA interface for an embedded systems

IrDA is a transmission standard commonly used in computer and peripherals like mobile phones. The primary purpose of IrDA is to provide device-to-device communication over short distances. IrDA solves the problem of usage cables, that may differ from machine to machine. With IrDA, no wires are required so this is easy to connect the same device to multiple device types like your mobile phone to laptops, other mobile phones or PDA’s. Full IrDA description can be found at https://www.irda.com. IrDa standard requires close communication of devices. This is low power transmission. It is essential because regulations are guarding the maximum level of IR radiation that can be emitted. Also, it is reasonable to assume that the two devices that are to communicate will be physically pointed toward each other before use. And only two devices can communicate at the same time. So IrDA doesn’t have to deal with collisions. And the main thing that IrDa is simple, cheap and require low-cost parts. The IrDA standard specification states that supported data rates can be between 2400bps and 115.2kbps over 1-meter distances. Later standard has expanded to support 1.152 and 4 mbps. Transmitter beam angle is from 15 to 30 degrees, and…

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Power up your electronics using potato batteries

Thomas Pfeifer does something new and amazing every day. This time he demonstrates how simple digital clock or LED diode can be powered by using batteries made of few potatoes and two different types of metal (iron and coper). Demonstration shows that such battery made from single potato generates 0.848V voltage and is able to to give up to 130uA. He used three potatoes connected in series to power digital clock or light the LED. More photos is here

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