How to read electronic circuits

In electronic circuit drawings there are two types of objects: component symbols and nets. Nets represent wires connecting the components – which represent physical devices. In a example bellow we see component type MAX3232. U2 is a reference label of component. Electronic component usually has pins. Pins always have their numbers starting from 1. Pins also have their names. They are usually written inside component block like C1+. Fig1. Component Reading For this particular component we used U2label. U (or IC) label applies to all semiconductors. But you know that resistors usually are labeled as R1, R3. Capacitors C1, C2, Diodes – D1, D2, Transistors Q1, Q2, Crystals – X1, X2, X3, Jumpers J1, J2, J3, Inductors L1, L2.

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Generic PCB design guidelines

How repeatedly make good PCB? Many hobbyists faces this issue every time they are prototyping their ideas. Designing the PCB layout (doesn’t matter is it a through hole or surface mount) may be tricky task especially when dealing with dimensions like 0.2mm tracks or 0.5mm surface mount pitches. Laser printer, plotting or other similar transfer technologies can’t deal with such dimensions. After I have tried photographic method of PCB artwork transfer, I don’t even want to touch Iron and laser printer. Using photosensitive laminate and single transparent media I can repeatedly make any number of PCBs. Benefits of using photographic methods are as follows: Transferred artwork is very clear, edges are smooth; Track thickness may be up to 0.2mm or even less with good mask quality, which can be made with good laser printer (usually new one). After printer cartridge refill – printing quality drops down; With one artwork mask I can clone many PCBs; Pay the biggest attention to artwork fabrication. Without good artwork you won’t be able to make good PCB. From My experience I can say, that I always do small mistakes with PCB artworks and I spot them usually after PCB is etched. Devote more time…

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Design and Implementation of DTMF Detector

Basic Extension Module for Embedded System Prototype By: Ivan Christian adn Daniel Widyanto < p class=”Section1″> Introduction Telephone units are ubiquitous. They can be found in almost every house. In some houses that has many rooms a line is paralleled so that anybody can receive and make call from different rooms. Their presence could be used for other purposes instead of making call per se. Application of this module can be found in smart home automatic system which incorporates telephone unit as input module. By using telephone unit somebody can make a control action to a remote system, as far as the telephone line can reach. To do so, such an interface between telephone line and the control system is needed. DTMF Detector 2.0 is designed for the purpose. 1. Description DTMF Detector 2.0 is a microcontroller system extension module which detects the presence of DTMF tones, and then decodes the tones to coded binary digits. By using DTMF Decoder 2.0 design engineer could interface the analog signal of telephone line with digital logic of microcontroller system in straight ahead manner. 2. Module Specifications The module specifications are as follows: 1. Input: · DTMF tones from telephone line (analog signal)…

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7-Segments-Board for Embedded Systems

  Design and Implementation of 7-Segments-Board 1.0 Basic Extension Module for Embedded System Prototype   By: Ivan Christian and Erwin   Introduction When developing embedded systems, it would be helpful if we could have a module for monitoring purpose. For instance, let say that your system has to process data streams. In testing and verification step, we need to compare each input and output bytes, so that we can verify that your system is doing right. Having a monitor module is surely a great help for engineers. Some development board has monitor module integrated, such as Altera UP1X FPGA Development Board. Inspired by its usage and benefit of such monitor, 7-Segments-Board 1.0 is designed as an extension module for embedded system prototype. Description 7-Segments-Board 1.0 is a low-cost low-power MCU extension module for monitoring purpose. Its aim is to help engineers doing the firmware testing and debugging on hardware prototype. For those who build microcontroller prototype device from scratch and do not have access to sophisticated debugging instruments, using this module would make testing and verification process less painful. 7-Segments-Board 1.0 is designed for 8-bit microcontroller system. Module Specifications The module specifications are as follows: Input: General purpose push-button (PB)…

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The site has launched a new forum

I am glad to announce that ScienceProg site has launched a new forum. It can be accessed by address forum.scienceprog.com. This is still new and quite empty. But I hope it will grow in to nice community. Please join and be first to post your message. All suggestions and advices about topic categories and threads are always welcome.

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AVR controlled signal generator-first impression

Lazy evening. I decided to take a couple of shots of couple generated signals. Without going too deep into timings, I wrote a couple of algorithms to make sure the signals are generated correctly at all voltage range 0-5V. First is the Sawtooth signal using ASM in AVRStudio:   .INCLUDE “m8def.inc” .DEF tmp = R16 ; Multipurpose register ldi tmp,0xFF; Set all pins of Port D as output out DDRD,tmp sawtooth: out PORTD,tmp inc tmp rjmp sawtooth (My oscilloscope is old so sorry for bad quality) <p > Second signal Triangle. This one I programmed using WinAVR toolset. int main (void) { uint8_t x=0, y=0; atmega8init(); for (;;) /* Note [6] */ { if (y==0) { x++; if (x==255) y=1; } else { x–; if (x==0) y=0; } PORTD=x; } return (0); } It is evident that signals are generated correctly at all voltage interval 0-5V. Later I will probably use signal (pulse, sawtooth, triangle, and sinusoid) tables stored in flash memory. EEPROM memory is too small to store all signals, but I am going to use it for last configuration storage that every time you switch that generator, the previous settings would be loaded. And I still didn’t decide…

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