My other robots based on the FRDM-KL25Z use Bluetooth as connectivity. This one is using a Freescale IEEE802.15.4/ZigBee/SMAC module:
Tag Archives: freedom board
Fix for 3.3V Voltage Drop on FRDM-KL25Z Board
With my Pololu line following robot I had strange problems with the sensor array: the sensor values were very unreliable. Until I have found the problem: Instead of the expected 3.3V, my FRDM-KL25Z RevD board provided 2.8V instead 3.3V on the P3V3 Arduino header pin:
And that voltage even was lower the more current I needed :-(. Luckily there is an easy hardware fix for this.
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Low-Level Coding with PDD (Physical Device Driver)
As with any software drivers: they are never perfect. The same applies to the Processor Expert components delivered in CodeWarrior for MCU10 or the DriverSuite too. That’s why I have created many more components which are available on GitHub here. All these components are using other components to reach the hardware. But what if a functionality is not exposed through the low-level component? Or what if I want direct access to the hardware? Up to now I had to choose either the Processor Expert way, or to do it in the ‘traditional’ way using an SDK like CMSIS or vendor supplied header files.
With MCU10.4, I noticed that there is another way: PDD (Physical Device Driver).
USBDM 4.10.5 supports now MCU10.4
Adding USBDM to CodeWarrior for MCU10.4
If you are following my recent posts, then you know I started using USBDM on OpenSDA as an alternative run control solution. Now with the advent of MCU10.4, the question is: how to use USBDM with it, because the USBDM installer obviously only knows the version up to MCU10.3?
Can MCU10.4 recover a bricked OpenSDA Freedom Board?
Ok, this one might not work for everyone. And maybe I’m seeing a ghost. But a nice and real one, at least for me :-). It seems that with the new CodeWarrior for MCU10.4 installation I was able to recover a bricked OpenSDA FRDM-KL25Z board 😯
Serial Bootloader for the Freedom Board with Processor Expert
Bootloaders are a very useful thing: it allows programming an application file without a debugger. This makes it ideal for upgrading a system in the field.
Usually, there are application notes and examples from silicon vendors available. But typically they are for a certain microcontroller, and hard to change it to another system without a lot knowledge about its implementation. What I need for a project based on the FRDM-KL25Z is a bootloader which shall be small and portable. As I’m using Processor Expert to keep my applications portable across different microcontroller families: why not create a bootloader with Processor Expert components? With the Processor Expert drivers available, things can get a lot simpler compared to the ‘traditional’ approach. With less than 10 KByte footprint?
USB CDC with the FRDM-K20D50M
Good news for everyone owning the FRDM-K20D50M board: I have extended the FSL_USB_Stack with USB CDC device class support for the K20D50M :-).
Debugging FRDM-KL05Z with USBDM
I mentioned in “Debug External Processors with USBDM and Freedom Board” post that I had a problem to debug the FRDM-KL05Z with USBDM. Well, after a long night with some sleep, with more thinking and searching, finally I have it resolved: I can debug my FRDM-KL05Z with USBDM 🙂
Debug External Processors with USBDM and Freedom Board
Teaching at a university means to work in a very special environment. What students love is ‘Open Source’: because it allows them to ‘see’ things and learn from the technology. The other thing is: students have a low budgets, so they appreciate if they can use inexpensive or low-cost hardware and software. The FRDM-KL25Z Freedom board for sure meets that low price, and no extra programming device needed.
Now they are building their own boards, and they wish to program and debug it. They can borrow the Segger J-Links and P&E Multilinks we have available at the university. But why not use the Freedom board as ‘hobby’ debug and programming solution? As explored in “Using the Freedom Board as SWD Programmer“, they can use the default factory installed OpenSDA to program another microcontroller of same type. But not to debug it.
While writing the “Using the Freedom Board as SWD Programmer” article, I was looking into USBDM. USBDM has added in January 2013 support for OpenSDA. But at that time, it was somehow not working for me, and I had not enough time to find out what the problem was. Time to get that fixed. Good news: With help and tips from the USBDM community, I have it finally working 🙂









