Data Logger with tinyK20 Board

First off: The tinyK20 project is progressing fine and is now on Hackaday.io :-).

For a research project we would like to use the tinyK20 to log gyro sensor data. For this I have created a quick-n-dirty project to explore how feasible it is. The tinyK20 has all the pins on the outside of the board, so I’m able to put it on a bread board:

tinyK20 on Breadboard

tinyK20 on Breadboard

The tinyK20 has been designed with the data logger as one of its applications. For this, there is a micro-SD card socket on the bottom side of the PCB:

Micro SD Card Socket on TinyK20

Micro SD Card Socket on TinyK20

The cool thing with the tinyK20 is that I can use it to debug another board. As a bonus, the tinyK20 is able to power the target board trough the SWD cable:

💡 The internal USB regulator of the Freescale Kinetis K20 is able to offer around 100 mA. I use the DC-DC converter on the backside of the tinyK20 to power more than the 100 mA.

tinyK20 debugging another tinyK20

tinyK20 debugging another tinyK20

I used a Segger J-Link to get performance data with the Segger SystemViewer.

Debugging with J-Link

Debugging with J-Link

Right now I’m logging dummy data. Checking the performance with the Segger SystemViewer for FreeRTOS shows around 20 ms to append 20 bytes to a file (csv format):

tinyK20 Data Logger with Segger SystemViewer

tinyK20 Data Logger with Segger SystemViewer

So far, I have plenty of power to do that data logger application, and I even have a shell with USB and the Segger RTT running :-).

If you want to have a look at that data logger project, it is on GitHub: https://github.com/ErichStyger/mcuoneclipse/tree/master/Examples/KDS/tinyK20/tinyK20_DataLogger

Happy Logging 🙂

Links

Advertisements

21 thoughts on “Data Logger with tinyK20 Board

  1. You’ve done a great job! This is much more flexible than the teensy. Where can I shop for the tinyK20? Does your PCB manufacturer also offer a BTO service for the assembled board?

    Liked by 1 person

    • Thanks :-). We were thinking about providing some of the boards for sale. It is a matter of demand and efforts. So right now there is no shop for it, but certainly could be considered.
      Our PCB manufacturer has not offered BTO service. Do you have a recommendation of a manufacturer doing this?

      Liked by 1 person

      • What about a Kickstarter project for this, Erich? Then you’d know the quantities up front. Just set your funding limit according to the number of boards you can sell.

        Like

      • Hi Dave,
        that board is something we did internally, with very minimal effort. Doing a Kickstarter project is by far something more time consuming. Plus I think the usual Kickstarter fee is 15-20% too. I have shipped some boards to the ones who have contacted me directly. I’ll be at the NXP FTF Technology Forum in Austin in May this year, so I could carry a few boards with me if there is any interest.

        Like

      • Yes, a KS is a bit of work, but if you’re careful with your calculations, you should be able to minimize risk (to losing money from your own pockets) 🙂 In large enough quantities, the tinyK20 could end up being pretty reasonably priced! Well, hopefully you’ll change your mind, or maybe someone else will run the KS for your design! I really like it and might have to order a batch from OSHpark to try it out.

        Like

      • Erich, I’d like to try out the tinyK20. Can you please name your price and payment preference, and I’ll be in touch with quantities? Thanks!!!

        Like

  2. Pingback: How to Add Bluetooth Low Energy (BLE) Connection to ARM Cortex-M | MCU on Eclipse

  3. Pingback: 3D Printed Magical MUFG Capsule to Duplicate NXP Kinetis K20 Boards | MCU on Eclipse

  4. Hi Erich,

    It looks like you have the MCU-VREGOUT shorted to the output of the output of the external 3.3V Vreg via R4 in your pictures, is that deliberate?

    Cheers
    Jim

    Like

  5. Hi Erich, I think that topology is risky, unless the regulators are perfectly matched current will flow between them.

    Like

  6. Pingback: Fascinating Details of Waveshare E-Paper Displays | MCU on Eclipse

  7. Pingback: First tinyK22 Board with NXP K22FN512 ARM Cortex-M4F | MCU on Eclipse

  8. Pingback: New Concept for 2018 Mini Sumo Roboter | MCU on Eclipse

What do you think?

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s