Sometimes I’m looking for a functionality, and I cannot find it. But this does not mean that it does not exist ;-).
The Eclipse preference pages have a great filter text field: If I want to change a setting which has something to do with ‘color’, I can enter that text and it will show me all setting pages having something to do with ‘color’:
Eclipse Preference Filter
Sometimes things take longer than anticipated. And this is definitely the case for my USB MSD Host project where I wanted to use a USB memory stick with the Freedom FRDM-KL25Z board.
Memory Stick attached to the Freedom Board
But finally, I have things working. At least most of the time ….
When I create a new project for the KL05Z with Processor Expert, then it shows up as 48 pin LQFP package in the project:
48pin LQFP Package in Components View
However, when I look at my board, it has a KL05Z32 in a LQFP package with 32 pins:
FRDM-KL05Z Board
The first FRDM-KL25Z Freedom Logic Analyzer firmware was missing one important feature: Triggers! But this weekend the firmware has evolved a bit :-).
Trigger Settings
After working on an ADC example, a DAC one was missing. Julio E. Fajardo is a reader of this blog, and he was so kind to send me an example project for the FRDM-KL25Z. The example is able to produce produce different waveforms with the DAC. The project has two examples which they are enabled/disabled in main(). One example waveform the sawtooth:
Sawtooth_FDRM_DAC
I’m using serial communication in different flavors for my project: with the shell, with OpenSDA USB CDC, to use printf(), and with the Bluetooth module. Processor Expert is a big helper, but as for any software, it is not bug free. And there is a problem with Processor Expert in CodeWarrior for MCU10.3 in respect with Baud settings for a serial interface.
Probing the Bluetooth Module Serial Connection
In “Using the Reset Button on the Freedom Board as User Button”, I had the problem to find out why a setting did not make it into my generated code. There is the fundamental question: “How does a setting impact my microcontroller register settings?”. There is an answer to that question: The Configuration Registers view:
Configuration Registers View
Processor Expert is a great tool: it lets me configure all the complexities of that ARM Cortex-M0+ core. But today it has fooled me and I lost several hours of my week-end time :-(. I need a user interface like push button for my project. Yes, the FRDM-KL25Z has touch area, but honestly: that kind of stuff never worked out well for me. It is probably just me having it not properly set up. The touch slider is working as in my earlier simple example, but in my other project with more hardware around it, it is working sometimes, sometimes not. Ahrg! I can blame my ignorance, my lack of understand how to configure it properly, or the extra noise by the hardware around it. Result is: I wasted a lot of time, and I give up :-(.
Reset button on the FRDM-KL25Z Board
I’m working now on a lecture robot project using my Freedom Board. And for this I need a wireless communication. I already have IEEE802.15.4 (SMAC) working, but I wanted to add Bluetooth as a low-cost option. I have found an inexpensive Bluetooth module which is available for only around $4-8 which we use in another university class project. The module is an AT command module: that means the microcontroller communicates with AT serial commands with the module, and the Bluetooth stack itself runs on the module. In a minimal configuration I only need 3.3V, GND, TX and RX plus a CMD (Command) pin:
Bluetooth Module
Unlike other boards from Freescale, the FRDM-KL25Z has no potentiometer or analog components on it. But in many applications an ADC conversion is needed, so here we go with a tutorial reading in an external potentiometer with Eclipse, CodeWarrior and Processor Expert. For this tutorial I have a 10k Ohm linear potentiometer connected to the Freedom board:
Linear potentiometer with the FRDM-KL25Z
MCU on Eclipse 