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

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

Handy 8051 MCU interfacing online tutorial

8051 microcontrollers are old but stil very popular. There are number of books is written about them and almost every IC manufacturer is producing 8051 core products. And why not, because there are tons of very useful products made upon 8051 microcontrollers. You can find very efficient microcontrollers with 8051 architecture(Flash, EEPROM memories, multiple peripherals, ISP, you may find ones that executes one instruction per clock cycle).   Mahesh Wankhede have edited nice handy tutorial about 8051 microcontroller interfacing to peripherals like I/O Ports LED, Switch, Relay, ULN, RS232C Cell Phones, GPS receiver, 7-Seg. Display, LCD Display, ADC & DAC, Sensors, Stepper Motor, DTMF Decoder, Keyboard, External Memory with relevant theory, schematics and sample codes in Assembly language and C language. For someone this may be a kick start to a new project. Continue reading

OpenBeacon RFID transceiver project

Open 2.4GHz RFID project is free design of active RFID device. Device has it own unique serial number which allows to identify it among others. Also device may have additional information that can be read. OpenBeacon can transmit and receive radio signals what allows to use it for variety purposes like tracking, and remote control.   Open beacon heart is Microchip PIC16F684 microcontroller with Nordic Semiconductors 2.4GHz NRF24L01 front-end chip. Transmitting range of beacon indoor reaches up to 25 meters. And 80 meters in open air. There is only beacon tag and USB reader circuits and firmware available freely. USB reader is built under AT91SAM7S123 ARM7 microcontroller which firmware can be compiled with GNU ARM-GCC compiler. Project authors says, that the next step would be to change the current node CPU (PIC) into an ARM based microcontroler with USB connection and the possibility to use GNU C/C++ compilers for programming issues. Also with small software modification at least two tags could communicate to each other without the need for base stations. Well seems like nice project to stick with. Continue reading

AVR chip computer runs basic programs

Jörg Wolfram has been developing interesting project so called AVR-ChipBASIC on Atmega32. Simply speaking this is a basic language programmable chip computer which his capable to run basic programs and with ability to display results in RGB TV screen.   This is almost fully functional computer system that have many functions including: RGB-TV 23 rows with 30 colums, NTSC/PAL per jumper selectable; prepared for FBAS encoder; 256 characters with pseudo-graphics, 8 colors; PS2 keyboard; simple sound (1 channel, 1 voice, noise); serial port (1200Bps only) with charge pump; parallel printer port, also usable for IO and ADC; I2C-port for data EEPROM and temperature sensors; ISP port is also able to handle Atmel dataflash; mostly Tiny-BASIC compatible with many improvements; 4 programs to 51 lines are stored in flash; built-in full screen editor; serial load/store via text transfer, listing print; screenshot function; integrated monitor with single step, breakpoints. Programs can be edited and run directly on TV screen and run from AVR chipbasic menu system. Also program can be saved, transferred via terminal or even printed. Firmware is updated constantly so… Continue reading