Mikroelektronika Flip'n'Click SAM3X

This Wiki page documents my trials an tribulations in getting a usuable NuttX development environment for this Flip'n'Click board. This board is an Arduino-Due work-alike with four Mikroe Click bus interfaces. Like the Arduino-Due, this board features the Atmel ATSAM3X8E MCU running at 84 MHz. And like all Arduino boards it is optimized to support Arduino sketches loaded via the Arduino IDE.

In the past with the Arduino Due, I was able to use Bossac to load NuttX. But I think that the Arduino Due tool environment has changed so much that that technique is no longer usable. At least I could not get Bossac to write firmware to the Flip'n'Click board (Refer to the board's https://bitbucket.org/nuttx/nuttx/src/master/configs/flipnclick-sam3x/README.txt file for the detailed, blow-by-blow of my attempts to use Bossac).

The alternative is to use JTAG and that is the subject of this Wiki Page

The JTAG Connector

The Flip'n'Click SAM3X comes with pads for micro 10-pin JTAG connector on board. However, connector is not populated. You will need to purchase the connector and solder it in place yourself as shown below. The connector shown here is the one recommended on the ARM.com website: Samtec FTSH-105-01-L-DV-K (for example from Digi-Key).

NOTE the orientation of the connector: The slotted side of the connector goes toward the inside of the board. This is necessary with the keyed connector in order to match up pin 1

JTAG Debugging

Connecting the Segger J-Link

I do most of my debugging with a Segger J-Link. This photo shows my Segger J-Link connected to the Flip'n'Click SAM3X. The stock J-Link does not support that tiny JTAG connector and will have to use an adaptor from the micro 10-pin connector to the standard 20-pin JTAG connector used on most debuggers. Shown here is the Flip'n'Click connected to the Segger J-Link using the Olimex ARM JTAG 20-10.

This photo shows the blue side of the board with the Arduino and JTAG connectors. See also the white side of the board with the mikroBUS Click connectors below.

J-Link Configuration / Sample Debug Session

nuttx.org_images_fnc-sam3x-debug.jpg

Serial Console

On a totally unrelated topic, this photo shows the white side of the Flip'n'Click with the four mikroBUS Click sockets. I am using an RS-232 Click module for testing here (because I had some difficulty with full duplex communications over the Arduino virtual COM port which is really the better option).

nuttx.org_images_fnc-sam3x-console.jpg

Serial console output with TeraTerm on Windows.

Acknowledgement

The Flip'n'Click SAM3X was contributed by John Legg of The Debug Store.