Freescale is a great manufacturer which sometimes isn’t considered among common players like STM or NXP. They like many produce ARM controllers and so offer several development boards to play with. One of well known freescale boards are Freedom Bord KL25Z which has ARM Cortex-M0+ microcontroller clocked at 48MHz. It features 128KB of Flash and 16KB of RAM. Board comes with USB OTG. The dev board carries MMA8451Q accelerometer, capacitive touch slider, and RGB LED. All GPIO are available for further prototyping or expansion boards.
Jan Henrik has covered this board on his instructable. He explains where to go next when starting with Freedom board. First of all he discusses software. Simply speaking all tools that are meant for ARM micros work with Freescale without problem. But fact is that Freedom board is MBED enabled, meaning that you can develop programs with popular online C/C++ editor, compiler and builder. Here you don’t have to wary about libraries and updates. So why not give a try. Then he goes through steps how to set up your first project in mbed.org and have it uploaded to board.
Every time you start with new microcontroller, you have to deal with new ways of programming them. You may need to purchase and learn new tools and so on. But once you’ve done this process with any microcontroller, learning new is easy. So if you are in to STM32 microcontrollers Shawon have written pretty god guide on programming them.
Since ARM Cortex micrcontrollers are flexible devices in terms of developing, debugging and flashing, you have several options of getting your code up and running. Like most manufacturers do, ST devices can be programmed and debugged with special ST-link adapter/debugger which works in JTAG or in SWD mode. Most development boards like discovery already have ST-link debugger integrated so the only thing is needed to run software and load your code. Other covered option is using built in bootloader which can be accessed through serial interface. ST have special software Flash Loader Demonstrator for programming in this mode. When programing with bootloader, special pins have to be pulled up or low in order to access it. This resource is great to start with and then you can dig deeper during development process.
There are tons of ARM development boards that are various sizes shapes and power. But when things turn towards battery operated gear, the lists shrinks down. We expect battery operated and portable electronics part to be small size and include all battery management circuit along with charging and DC/DC conversion. Vsergeev introduces his version of small ARM Cortex-M0 powered board.
He wanted his board to be small size, battery operated (USB as well) and be low price. The board size came out to be 70x43mm, it carries NXP LPC1114FDH28 32-bit ARM Cortex-M0 microcontroller. Additionally there is a 16-Mbit SPI FLASH memory. As mentioned before, board canbe powered from USB (Mini-B) or LiPo battery. Battery can be charged with onboard LiPo charger IC (MCP73831T). There are 4 LEDs on board along with two push buttons and 2 DIP switches. For more IO capability there is also an I2C 8 additional I/O pins expander. So there is total 16 I/Os on header, SWD for flashing and debug and 6 pin UART header that matches popular FTDI adapters for USB to serial feature. Project files are open and accessible on GIT.
Rotary dials are long gone since everything went digital. Now every device is equipped with keys or touch sensitive input interfaces. But if you feel a little nostalgic about old times you may find this project really interesting. This is a custom made mobile phone with rotary dial for input. We already know that building mobile phone isn’t that hard when you already have GSM modules around. All you need it so hook everything to microcontroller and LCD and you are up to go.
jaromir instead of adding buttons or touch sensitive LCD went with simpler but yet interesting solution – a rotary dial. The phone is controlled with 8-pin DIP NXP LPC810 ARM Cortex-M0+ microcontroller. He had to squeeze everything to fit 6 IO pins. Shift register solves a lot here. No matter if it looks cool, making calls, entering PIN numbers can be real pain, but it works. As a phone it has huge enclosure due to large rotary dial size. You will definitely amaze your mates when taking calls. More pictures of it at Picasa.