If you weigh yourself by standing on a bathroom scale, not liking the result, then balancing towards one corner to knock a few pounds off the dial, you are stuck in a previous century. Modern bathroom scales have not only moved from the mechanical to the electronic, they also gather body composition measurements and pack significant computing power.
After a struggle with double-sided sticky pads, the scale revealed its secrets: a simple yet accomplished device. There are four load cells and the electrodes for the body measurement, and the PCB. On the board is a 120 MHz ARM Cortex M4 microcontroller, a wireless chipset, battery management, and the analogue measurement chipset. This last is particularly interesting, a Texas Instruments AFE4300, a specialised analogue front-end for this application. It’s a chip most of us will never use, but as always an obscure datasheet is worth a read.
Finally, the wireless antenna is not the normal simple angular trace you’ll be used to from the likes of ESP8266 boards, but an organic squiggle. It’s a fractal antenna, presumably designed to present a carefully calculated bandwidth to the chipset. A nice touch, though one the consumer will never be aware of.
Raspberry Pi 3, with its quad-core ARM Cortex-A53 processor, is our first 64-bit product, supporting ARM’s A64 instruction set and the ARMv8-A architecture. However, we’ve not yet taken the opportunity to ship a 64-bit operating system: our Raspbian images are designed to run on every Raspberry Pi, including the 32-bit ARMv6 Raspberry Pi 1 and Raspberry Pi Zero, and the 32-bit ARMv7 Raspberry Pi 2. We use an ARMv6 userland with selected ARMv7 fast paths enabled at run time.
There’s been some great work done in the community. Thanks to some heroic work from forum user Electron752, we have a working 64-bit kernel, and both Ubuntu and Fedora userlands have been run successfully on top of this.
SUSE and ARM distributed these natty cased Raspberry Pi units at last week’s SUSEcon
Which brings us to last week’s announcement: that SUSE have released a version of their Linux Enterprise Server product that supports Raspberry Pi 3.
Why is this important? Because for the first time we have an official 64-bit operating system release from a major vendor, with support for our onboard wireless networking and Bluetooth. SUSE have kindly upstreamed the patches that they needed to make this work, so hopefully official support from other vendors won’t be far behind.
You can download an image here. Give it a spin and let us know what you think.
Uptill now I used 0603 sized resistors and capacitors but for this project I switched to 0402 to save a few mm on the board. I have soldered many challenging chip packages so I felt confident. The technique is the same as for bigger sized devices: flux the area generous, hold the device with tweezers, solder one pad with fresh soldered iron and move the device into the molten solder puddle, retract the soldering iron and watch the solder joint cool down. If the solder joint is solid solder the other side too. I suggest using a fine (curved) tweezer and lots of lighting on your workarea. If you are a bit older as I am using a loupe or magnifying glass. Still use flux as much as possible. Never expected but the micro USB connector gave me (several) headaches to get it soldered properly.
Playing with RFID and NFC is definitely fun, and they are everywhere! For a research project I’m exploring different RFID tags and solutions. I several types around for a long time, but never found the time to actually work on it, so last nightI thought I give it a try, and I have it working with GNU ARM and Eclipse, powered by the NXP FRDM-K64F board
As many of you already noticed, we recently released a new “Linux ARM” version of the Arduino IDE available for download on our website together with the usual “Linux 32bit” and “Linux 64bit.”
This release enables you to run the Arduino Software (IDE) on many of the mini PC boards based on ARM6+ processors currently on the market, including Raspberry Pi, C.H.I.P., BeagleBone, UDOO… just to name a few.
The Linux ARM release has been strongly supported by our community and we would like to thank all the people that helped to make this happen: GitHub handles @CRImier, @NicoHood, @PaulStoffregen, @ShorTie8, and to everyone that patiently tested and reported problems.
If you are interested (and brave!), you can read the full story and explore the complete list of collaborators below:
I’m using the tiny and inexpensive Nordic Semiconductor nRF24L01+ transceiver (see “Tutorial: Nordic Semiconductor nRF24L01+ with the Freescale FRDM-K64F Board“) in many projects: it costs less than $3 and allows me to communicate with a proprietary 2.4GHz protocol in a low power way (see “IoT: FreeRTOS Down to the Micro Amps“). I have that transceiver now running with the tinyK20 board too.