Over the last few months I have been playing with the Nucleo development boards from STMicroelectronics. If you’re unfamiliar with them, they are fast, mbed and Arduino (headers) compatible. This makes it easy like an Arduino to program and use. What sets them apart is that they are 32bit and have, depending on the model, tons of memory and flash. The Nucleo boards maintain the Arduino footprint but also have headers for the extra pins which gives this board plenty of GPIO for your projects. In turn, you end up with multiple buses such as SPI, I2C, and UARTs for your consumption. They are priced very well and come in different flavors based on your needs. Each flavor is based on different ARM Cortex architectures such as M0, M3, and M4. One of the best features is real debugging via ST-Link/V2-1. The unfortunate thing due to the nature of mbed, you can only use the debugging features using a full desktop IDE such as Keil or some of the other free alternatives. But mbed allows you to export your code from the online IDE to the project format for those IDE’s. So there’s that.
More details at MobileWill’s project page.
I’ve been doing mostly sensor-based systems and I think these microcontrollers are the perfect fit. ARM Cortex (they go from M0 to M4, and their series seem to keep growing), an architecture that was specially designed for low-power sensor-based embedded systems, allowing to measure “stuff” while the CPU is stopped, a nice set of peripherals (OPAMP, 12bit DAC and ADC), great support for GCC ARM Embedded (which makes them really ease to use or getting started to) and a factory-programmed UART bootloader.
The bootloader uses XMODEM-CRC protocol and TeraTerm may be used for uploading. However if you want a command-line tool (like “avrdude” for AVR microcontrollers), there’s anything you can use. So, I built one.
Source code is on Github.
Via the forum.
Project details at Mário Ribeiro’s blog.
Shawon Shahryiar over at Embedded Lab has written an article on XMega analog comparator:
Generally a comparator is a device that compares two quantities. Analog comparators compare voltage – an analog quantity. An analog comparator is essentially an op-amp with infinite gain. It has one output and two inputs. The output is switched to VDD or ground (0V) depending on the relative voltage levels in the two input pins. Just as with an op-amp the two inputs are labeled as inverting input (INV) and non-inverting input (NINV). When the non-inverting input voltage is higher than that of the inverting input, the output switches to VDD and when it is the other way, the output switches to ground. Thus we get two logic states.
Details at Embedded Lab blog.
Brian Dorey has designed and built a PIC24 development board, that is available at GitHub:
One problem we found was trying to prototype code using this microcontroller as unlike Arduino and any ARM microcontrollers there isn’t a small easy to use prototyping board available for the PIC24 chip. Microchip make an Explorer 16 Development Board which is designed to work with the PIC24 microcontrollers but it is large and fairly expensive and is designed to work best with other Microchip addon cards.
With this problem in mind we decided to design and build a small prototyping board that would work with the PIC24FJ128GC006 as well as one of Microchips DSPIC33EP256MU806 dsPIC series microcontrollers.
The prototyping board was designed with removable daughter boards for the microcontroller.
Project info at Brian Dorey’s blog.
Last Monday was the last time I’ll be leading Circuit Hacking Monday at Noisebridge for several weeks. It was lots of fun! There were almost 40 people there, making TV-B-Gones, Trippy RGB Waves, Arduino clone kits, and other cool kits that I created to teach people how to make things with electronics. Several people learned to solder for the first time! Some people brought in their own cool projects to work on. And some people brought in their old, broken electronics that are now working again, thanks to the helpful geeks at Noisebridge.
While I’m gone, Miloh will be leading Circuit Hacking Monday workshops.
Over the next several weeks I’ll be traveling the planet, giving talks and workshops everywhere I go: Lisbon, Singapore, Berlin, NYC, Boston, and hopefully other places out East where I’ll be visiting (Philly, Baltimore, DC).
I’ll be gone till the beginning of February!