Cheap and Simple WiFi with ESP8266 for the FRDM Board

How cool would it be to add WiFi support to any projects or IoT? Why not using WiFi with a microcontroller which has only few KBytes of RAM and FLASH. For less than US$5? Dreams came true, and intrigued by an article at Hack-A-Day, I searched a supplier for that ESP8266 module. And this evening I have found the four ESP8266 modules I have ordered for $4.50 each from ElectroDragon in my mailbox. Of course I did not want to wait for the week-end, so I hooked it up to my FRDM-KL25Z board.

ESP8266 Module

ESP8266 Module for US$ 4.50

Continue reading

User Interrupt on NMI Pin with Kinetis and ExtInt Component

While my beef brisket (see “My First DIY Smoked Beef Brisket: Day 1“) is smoking on ;-), I have time to investigate a problem I was running on in my lecture on Friday: For the Joystick shield (see “JoyStick Shield with the FRDM Board“) on the FRDM-KL25Z board, I wanted to use an interrupt if I press the green button:

No Interrupts for Button C

No Interrupts for Button C

However, that did not work :-(.

Continue reading

Unlocking and Erasing FLASH with Segger J-Link

When using a bootloader (see “Serial Bootloader for the Freedom Board with Processor Expert“), then I usually protect the bootloader FLASH areas, so it does not get accidentally erased by the application ;-). When programming my boards with the P&E Multilink, then the P&E firmware will automatically unlock and erase the chip. That’s not the same if working with the Segger J-Link, as it but requires extra steps.

Protected FLASH Pages with Processor Expert

Protected FLASH Pages with Processor Expert

Continue reading

Comparing CodeWarrior with Kinetis Design Studio

At FTF 2014, Freescale made the announcement that CodeWarrior won’t support all the new ARM Kinetis devices coming out in the future: they will be supported with the free-of-charge Kinetis Design Studio (KDS) instead. As for myself, this is a big shift from a well established CodeWarrior toolchain to something new. A question which came up recently several times in the forums and in other posts is: how do CodeWarrior and KDS compare with each other?

CW vs KDS

CW vs KDS

Continue reading

Semihosting with GNU ARM Embedded (LaunchPad) and GNU ARM Eclipse Debug Plugins

In “Semihosting with Kinetis Design Studio” I used printf() to exchange text and data between the target board and the host using the debug connection. Kinetis Design Studio (KDS) has that semihosting baked into its libraries. What about if using the GNU ARM Embedded (launchpad) tools and libraries (see “Switching ARM GNU Tool Chain and Libraries in Kinetis Design Studio“)? Actually it requires two more steps, but is very easy too.

Semihosting Output

Semihosting Output

Continue reading

P&E Eclipse Update Site for GNU ARM Eclipse Plugins

P&E has just released a new version of their Eclipse plugins for the set of GNU ARM Eclipse debug plugins. The GNU ARM Eclipse plugins from Liviu support OpenOCD and Segger J-link, so with this update or extension it adds P&E support to it. With this, I can use the P&E debug devices (P&E Multilink, Tracelink) or as well the Freescale OpenSDA with it.

PnE Debug Interfaces

PnE Debug Interfaces

Continue reading

GNU Libs with Debug Information: Rebuilding the GNU ARM Libraries

With my DIY tool chain (see “Constructing a Classroom IDE with Eclipse for ARM“) I get a complete tool chain. I do not need to build that tool chain from the sources for Windows, as all the binaries are nicely pre-compiled and made available. But there is one issue I face from time to time: as the libraries provided by ARM do not come with sources and debug information enabled, I end up with that “No source available for …” message in the debugger:

No Source Available

No Source Available

The solution is to grab the C/C++ library sources from the ARM launchpad site and get it built locally the way I need it.

Continue reading

Review of the CAM8100-U USB Camera with the RIoT Android Board

In my earlier post (“Adding the CAM8000-D Camera Module to the RIoT Board“) I was running into the ‘single camera’ trap of the current RIoT Android OS image: with only one camera attached, and switching between front/back camera, Android is stuck and needs to be flashed again to the board. Because this is so painful and can happen easily, I OKordered a USB camera for the RIoT board: with this that problem should go away, and I would have a front and a back camera.

CAM8100-U Camera Module with RIoT Board

CAM8100-U Camera Module with RIoT Board

Continue reading

Hacking the Teensy V3.1 for SWD Debugging

I *love* the Freescale Freedom boards, and you probably recognized that with all my projects using them. The Freedom boards are small, inexpensive and can be easily extended with Arduino shields which makes them a great platform for prototyping. But sometimes I just need an ARM microcontroller with some headers, and then the 85mm x 55mm size of the Freedom board is not ideal. That’s nothing new, but I realized that yet again when I did my Adafruit NeoPixel clock: the FRDM board was rather bulky, even if hidden behind that clock. I need something much smaller: the Teensy board!

Size Comparison FRDM vs. Teensy

Size Comparison FRDM vs. Teensy

Continue reading