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

AVR graphical LCD test board

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… Continue reading

Simple USB to OBD2 adapter on PIC18F2455

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… Continue reading

Displaying text on a bicycle wheel

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

Multipurpose tiny AVR microcontroller board

Raph has designed this board for NES/SNES controllers to USB, but it found place in many more projects due to its small size and easy to use. This board is only 27.5×17.7mm size and is equipped with Atmega8 microcontroller. Circuit is already adapted for Firmware-Only USB Driver from Objective development including 12MHz resonator. Also there are several I/O pins available for custom programming. Because board it self is double sided, there is a place for SMD voltage regulator. Check out following projects where tiny board was used: X2Wii: N64, SNES or NES Gamepad to Gamecube/Wii adapter USBTenki: USB-connected temperature, humidity and pressure sensors. Infra-red receiver for Kenwood keyboard Gamecube/Nintendo 64 controller to USB adapter Four NES and/or SNES controllers to USB adapter Atari style joystick/controller to USB adapter Board is… Continue reading

Interfacing IDE hard drive with 82C55 microcontroller

Have you ever thought about of having huge amount of backup memory in your embedded system. The only cheap way is to connect IDE hard drive. And it seems that interfacing IDE isn’t that hard as it may seem.   The software provided for download doesn’t support any of file system formats like FAT16, FAT32 or any other. It just provides ability to access raw sectors. With 82C55 microcontroller running at 14.7456MHz reading speed reached 24 kbytes/s. Continue reading

AVR Network Time Protocol Clock

There are many time servers around the world that provide reliable time by using NTP (Network Time protocol). Everyone can connect to these serves and receive exact time via this simple protocol. Read more about how does it work in https://www.pool.ntp.org/. Guido Socher from tuxgraphics.org has built nice simple NTP client that can request for time packets from server and display this data on LCD.   He used one of his AVR ethernet boards where simple server application allows easily configure clock settings like NTP server address, time offset, Clock address and more. The web server has also a second page where current time is displayed – the same as on LCD. Author provides ideas on how to build clock, ad even provides source code, but if you just want… Continue reading