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Universal RC5/RC6 transceiver with LCD indication

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Universal RC5/RC6 transceiver is originally developed by Frits K. Raalte. It is a nice tool to analyze RC5, RC5X or RC6 IR signals. Also it can transmit every possible RC5, RC5X or RC6 protocol based code like a IR remote control does.   Device is capable to receive signal and display its code on LCD as decimal and binary code(meanings of codes see here and here ). Additional three LEDs indicate receiving phase(green), toggling between decimal and binary code on LCD is indicated by yellow LED and red LED indicates bad code or unknown standard. When transmitting IR code, there is one button which allows to adjust code and another is for sending command. This way any code can be sent. I wouldn’t call this toy a universal remote as it would be un convenient to select codes each time when you want to lets say change channel or change volume. It is more for testing purposes, where it is a “must have it”. Project files are available for download (Circuit, PCB and binary for PIC16F268 ). Continue reading

Countdown timer for PCB exposure

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Countdown timer can count fro m1 second up to 99 minutes and 59 seconds. Ideal tool for PCB maker when need to control PCB exposure with ultraviolet light. Timer is equipped with alarm when countdown finishes.   Timer has it own power supply unit, so you can plug it to AC outlet and start counting. The counter is based on old good PIC16F84 which counts time and drives 4 seven segment LED displays. Timer can be controlled by three buttons. One Starts/Stops timer, second sets time for each of digits, and last button allows to select preset times from EEPROM-convenient for quick time select. Project files are available for download. Continue reading

PIC based caller number identification

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This device works with dial tone (DTMF) protocol. And its working depends on your phone company. If it sends phone numbers to call recipient that it is OK. The device simply detects and analyses phone line activity and detects incoming callers phone number which then is stored in EEPROM memory.   Device can remember up to 10 phone numbers in PICs EEPROM memory. Numbers can be erased at any time. Project files are available for download. Continue reading

AVR graphical LCD test board

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Graphical LCDs with KS0108 controllers are used for quite long time like widely used HD44780 Text LCDs. So there are many projects and information available around the internet. Scienceprog has build simple single sided board for HQM1286404 128×64 graphical LCD with same KS0108 controller. The board can be equipped with Atmega16 or Atmega32 depending on memory needs. Also it has many other available features that allow to reach various complex applications on single board like 16MHz speed for high speed ADC applications, ISP for fast programming, RS232 communication block, potentiometer adjustable analog reference voltage (AREF) from 0 to 5V, graphical LCD with contrast potentiometer, 3 ADC inputs, 10 I/O pins, reset button, 5V voltage regulator on board. PCB small(100x50mm) single sided without wire strips. There you can also find program demo which KS0108 control library, and all other project files included. Continue reading

Simple USB to OBD2 adapter on PIC18F2455

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AS COM ports are disappearing form computers – especially from laptops, there are more and more USB to RS232(COM) adapters showing up in the Internet. The bigger choice the better to end user – he can look and build the best solution that fits his needs. This particular adapter was developed by Alex Sidorenko and its main purpose was to comply RS232 to USB of car ODB(On-Board Diagnostic) unit.     Adapter is equipped with 9 pin D type female connector to match most OBD2 cables available commercially. Adapter doesn’t require any special drives as it uses standard Communication Device Class(CDC). Just download CDC driver plug the adapter and this way create a virtual com port. The layout in Gerber format available for download here. The adapter schematic is really simple and easy to trace on single sided board and don’t forget to flash firmware . Too lazy to build one? – author can sell the blank PCB of adapter and preprogrammed chips by request.   Continue reading

Displaying text on a bicycle wheel

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This is so called persistence of vision when the perceptual processes of the retina of the human eye retains an image for a brief moment. Such inertia causes an illusion of motion rather separate frames displayed in quick succession. So this illusion technique can be used in many areas. Probably you are avare about rotating clock projects so why not to put similar technique in bicycle tire and look cool in the dark.   Raphaël Assénat have been developing a rotating LED bar on bicycle wheel for quite long time and came up with several versions of project. The newest is capable to read RPM of wheel and display value with LEDs. Also Display scan rate is fixed what allows to display smoothly at any rotating speed. Continue reading