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

Simple and small portable AVR MP3 player

I bet that using devices that you have built is an exiting feeling. So why not to listen MP3 songs with your own MP3 player. So Michael does. He have been developing a simple portable MP3 player powered by Atmega128 microcontroller and VLSI VS1011b MP3 decoder IC.   MP3 player reads songs from MMS/SD data media where also playlists and skins can be stored. Player is powered from LiIo/LiPo battery which can be charged easily with included charger in to circuit itself. Color displays (128×128 pixel and 256 color) is taken from Nokia 6610 cell phone so plauer can work in both – text and graphical modes. All firmware is written in easy accessible WinAVR C language. Media supports FAT32 file system so there is no problem to write songs directly from PC. Other features include: Written in C for WinAVR compiler based on avr-gcc v3.4.5 or higher including avr-libc v.1.4.3 or higher Direct M3U playlist support; ID3 v1 & v2 tag support ; Color skin/theme support; Adjustable LCD contrast, backlight brightness and auto off time; Sass enhancer in VS1011b,… Continue reading

Numeric Simon memory game on Olimex PIC-MT Dev Board

If you have a Olimex PIC-MT Dev Board near by, you may want to try this popular Simon memory game modification that has been developed by geeksinside. Geeksinside did a review of the Olimex PIC-MT development board so you may easier to decide if it fits your needs. Or there is another option. They are currently running a tips contest this month and giving away a second Olimex PIC-MT. So don’t hesitate and try your luck. Continue reading

AVR USBtinyISP programmer and SPI interface

Seems like everyone is shifting their own ISP programmers from COM and LPT ports to USB. And there is a reason for this – computers arre getting mobile, LPT and COM ports becoming obsolete. But almost everywhere you can find USB port, so it is logical to have USB programmer rather then old style. ladyada have developed very tiny USB ISP programmer which also can serve as USB-SPI interface. Thisis really low cost and low component count programmer built under Attiny2313 AVR microcontroller. It is compatible with AVRDUDE and AVRStudio and works under Windows, Linux and MacOS.   This is not the fastest programmer but it can guarantee write speed of1 Kb/s and read speed of 2Kb/s. Other good feature is that it comes with both – 6 and 10 ISP connector types. You can build this adapter easily as all necessary files are available for download, or you can simply order a kit. Continue reading

32bit single board computer on 68HC000

While looking for better performance than 8 bit microcontrollers Wichit Sirichote have constructed 32bit single board computer on old 68HC000 chip. He spend couple of months to finish his project and made quite powerful kit that is capable to run embedded linux.   Computer board features 68HC000 32 bit microcontroller running at 8 MHz speed, 256kB of FLASH memory and 256kB of SRAM. Other features include: GPIO: 8-bit output port, 8-bit input port, UART: 6850 9600 8n1, RTC: DS12887, Glue logic: DTACK, memory/io decoder, Xilink XC9572 CPLD, Monitor program: zBug V1.0 for 68000-Based Single Board Computer. There is also CPLD Xilinx 9572 used in board computer for decoding memory and generating necessary logic signals. Author intended to use this board to run GCC compiler. If you want to give a try – all files are available for download, but keep in mind that it is not easy project for beginners. Continue reading

Very simple countdown timer with 7 segment displays

This is very simple countdown timer implemented on 89C2051 microcontroller. One button is used to set time up to 99 seconds, another is for starting timer. Time is displayed on two 7 segment LED displays.   Buttons and display scanning share same pins so algorithm has to check buttons and display time on LED displays in a row sequence. Source code is included that allows yo modify program and compile. Continue reading