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

Running uClinux on ARM microcontroller

ARM microcontrollers are 32 bit systems with high potential. It is enough power to run small operation systems like uClinux. The only limitation is that operations systems require much more program memory than internal chip memory can provide. Ulrich Radig used a NXP LPC2294 ARM7 microcontroller which carries 256K of internal Flash memory which is enough to place a boot-loader which loads uClinux kernel to SRAM.   It interesting how he solved low memory problem. SD card was split in to two partitions where one partition FAT16 was used to store kernel which has to be loaded to memory, second is Linux (ext2) partiion for custom use. To support this he has written a simple driver. When Linux is loaded, it is easy to run various custom programs like web servers, and so on. Continue reading

Simple flash card audio player

Moving along the Philips ARM Design Contest 2005 projects list there is another interesting project you may find interesting. Its a flash card audio player which plays lossless audio tracks directly from MMC flash card. Interesting thing is that player is controlled by car audio head-end unit.   The idea was to emulate a CD changer so the head-end could be adopted to communicate with player. Instead playing CD tracks player changes the tracks in subdirectories. Each subdirectory appears as different CD to head-end unit. Other commands like play, stop, next CD, next track are normally supported. Audio signal is converted do analog through external high speed stereo DAC. Signal is sent back ti head-end unit for amplification after when music reaches speakers. Nice project probably more for learning purposes rather than practical. Download files here. Continue reading

Sophisticated telephone answering machine

This project is developed by Bernard Debbasch and is a winner in Philips design contest 2005. it is really cool and flexible answering machine which allows many things including Media storage, internet access where messages can be sent in form of SMS or e-mails, interfacing to phone line, DSP routines. Answering machine(TAM-TAM) also supports multiuser interface where up to four users can have custom settings.   The whole machine is built around LPC2138 ARM7 RISC microcontroller. Project gives a good demonstration of DSP functions including FSK demodulation, voice playback and record, DTMF tone generation and detection. Concurrently there are also running IP stack and File system management tasks. And still, whole system gives good level of performance. Code blocks are written so that they may be easy reused in other projects. All project files are available for download. 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

LPC213x development board

If you need simple LPC213x ARM microcontroller series test board you should try the one Ulrich Radig has constructed.   Board itself is simple but it covers all I/O that allows to cover all microcontroller functionality. Project files are available for download in Eagle CAD format. Continue reading

Build your own LPC210x prototype board

If you need simple LPC210x prototyping system, this project is right for you.     Despite board simplicity it has all peripheral connectivity covered including RS232 interface for easy bootloading flash memory, JTAG and other if needed. There is plenty of space on board for other circuitry, that can be wired directly on prototyping area. So it may serve as learning tool or for complete project. Author provides PCB files so that everyone could build it by himself. Continue reading