Sometimes I think that a problem should be solvable in a few minutes, and then it turns out that it lingers around for months. Very, very frustrating! Such a thing is getting the USB 4.1.1 stack running on the FRDM-K64F board. I have that board since April 2014, and it took me 7 months to get the FSL USB stack running on it :-(.
FRDM-K64F Board
Finally, after several weeks delay, the new PCBs for the Mini Sumo Robots (see “Zumo Robot with WiFi and GPS”) arrived, and best of all: first test are all running fine :-).
First PCB under Debug
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 $4.50 each from ElectroDragon in my mailbox. Of course I did not want to wait for the week-end, so I hooked it up to my FRDM-KL25Z board.
ESP8266 Module for US$ 4.50
Found an interesting behaviour with the Freescale FXOS8700CQ on the new Sumo Robots (see “Sensor and Communication Shield for Sumo Robot“): when enabling the accelerometer/magnetometer, it actually did not work:
Failed to Enable FXOS8700 Accelerometer
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
However, that did not work :-(.
I have to admit: I’m not a vegetarian. I love BBQ, and no offense to vegetarians! Today is perfect day for another BBQ session, and this time I plan to enhance it with electronics. No, not eating electronics, but doing BBQ with a little DIY electronic helper. There are different ways to cook meat on an open fire pit, and each region of the world has its own way to do it. Traditionally, in my area we are ‘grilling’ the meat: high temperature, for a few minutes, done! I like that ‘fast food way’ too, but there is an even better version: Slow food smoking!
I’m gifted that I had the opportunity to experience the Texas BBQ culture: slowly cooking the meat, at low temperature, and ‘smoking’ it: Cooking the meat around 80°C prevents that it gets dry (because the water does not vaporize, see this article on Wikipedia). There are different ways how to do this, but I love the way how it is done at the Salt Lick in Austin/TX with an open fire pit:
BBQ Pit in Austin Texas
The semester started last week. Ideally I wanted to have the boards for the new S robot (see “Zumo Robot with WiFi and GPS“) ready in the first week. But our manufacturer was not able to get the four-layer boards with parts populated and delivered in that time frame. Until the new boards arrive, we have anyway plenty of things to cover. One thing is to build a prototype shield to host several distance sensors, nRF24L01+ and Bluetooth transceiver:
Sumo Robot with Sensor Shield and Sensors
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 ordered 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
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
When I ordered my first Freedom FRDM-KL25Z board, I placed an order the Tower TWR-KL25Z48M shortly afterwards. But I was so happy with the FRDM-KL25Z, and because the FRDM board is much less expensive and easier to handle, that Tower board was sitting in my board shelf, waiting for a maybe a student project or to get any other use of it. Well, I can tell that my students wanted the FRDM board, not the Tower board ;-). But when I saw this week in the Freescale forum a user asking for a USB example for that Tower board, I thought that now I could at least use that board to help someone out.
MKL25Z128VLK4 on the TWR-KL25Z48M Board
MCU on Eclipse 