Tag Archives: ARM

Debugging ARM Cortex-M0+ HardFaults

via Dangerous Prototypes

next-step-will-be-a-hard-fault

Erich Styger has written an article on debugging a hard fault on an ARM Cortex-M0+ device:

To me, one of the most frustrating things working with ARM Cortex-M cores are the hard fault exceptions. I have lost several hours this week debugging and tracking an instance of a hard fault on an ARM Cortex-M0+ device.

More details at MCU on Eclipse homepage.

JeeNode Zero

via Dangerous Prototypes

pics-DSC_5619-600

JeeLabs has been working on a new board called JeeNode Zero:

Enter the STM32, the 32-bit ARM series from STMicroelectronics which has been around for several years, with new chip releases at a breathtaking pace. While most of the more advanced chips are only available in 64-, 100-, or even 144-pin packages, there is also an active line of smaller chips in 20- and 32-pin versions. For these, the STM32L series is particularly interesting from a low-power standpoint, with its “stop” and “standby” mode power consumption in the single microamp range, sometimes even lower.
And so the idea was born to try and design a new entry for the JeeNode family, which would again combine a µC with a low-end radio, i.e. the RFM69 successor of the RFM12.
Since there are no DIP versions of the STM32’s, the size can be made considerably smaller than the ATmega-based JeeNode v6. It all ended up being a unit of about 20×40 mm, with all the components on one side, and a large “main header” to support solderless breadboards

Project info at Jeelabs homepage.

JeeNode Zero

via Dangerous Prototypes

pics-DSC_5619-600

JeeLabs has been working on a new board called JeeNode Zero:

Enter the STM32, the 32-bit ARM series from STMicroelectronics which has been around for several years, with new chip releases at a breathtaking pace. While most of the more advanced chips are only available in 64-, 100-, or even 144-pin packages, there is also an active line of smaller chips in 20- and 32-pin versions. For these, the STM32L series is particularly interesting from a low-power standpoint, with its “stop” and “standby” mode power consumption in the single microamp range, sometimes even lower.
And so the idea was born to try and design a new entry for the JeeNode family, which would again combine a µC with a low-end radio, i.e. the RFM69 successor of the RFM12.
Since there are no DIP versions of the STM32’s, the size can be made considerably smaller than the ATmega-based JeeNode v6. It all ended up being a unit of about 20×40 mm, with all the components on one side, and a large “main header” to support solderless breadboards

Project info at Jeelabs homepage.

Body Cardio Weighing Scale Teardown

via hardware – Hackaday

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.

Yet they’re a piece of domestic electronics that sits in our bathroom and rarely comes under scrutiny. How do they work, and what do they contain? The team at November Five tore down a top-of-the-range Withings Body Cardio scale to find out.

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.

The rather pretty fractal antenna.
The rather pretty fractal antenna.

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.

We’ve shown you quite a few bathroom scales over the years. There was this wisecracking Raspberry Pi scale, this scale reverse engineered to gather weight data, and this one laid bare for use as a controller.


Filed under: ARM, hardware

SUSE Linux Enterprise Server for Raspberry Pi

via Raspberry Pi

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

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.

The post SUSE Linux Enterprise Server for Raspberry Pi appeared first on Raspberry Pi.

First GD32 tests

via Dangerous Prototypes

gd32f103-1080x675-600

Sjaak has published a new build, the STM32/GD32F103 QFN32 breakout board:

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.

Project info at smdprutser.nl