J22 port not working on Rev-3 SAM9x60 boards

We have 2 different versions of the Sam9x60 Evaluation boards i.e. Rev B and Rev 3 being Used for our initial board bring up and product development across the sites.

Part number : 150-DT100126-ND DT100126


On Rev B, j22 is working by default as the COM port even before the boot and printing RomBoot after every reset.

But on Rev 3, it is not working as the com port. we need to use a TTL to usb converter on J23 to get the serial console working.

Is there a way to enable J22 so that we can use it for serial console directly like we do on Rev-B boards ?


Hi @skreddy, let’s please verify a few things on the non-working board:

J2 - Closed
J3 - Open
J13 - Open (Boot from internal memory)
J20 - Open (SAM3U J-Link routed to J22)
J21 - Open (Enable UART on SAM3U)

J7 is used for power…

J22 should now have a serial terminal, although customer may still have to push the “reset” button…


Yes, We have verified all the settings.
The board is not powering “ON” as J3 is removed. But the USB is detecting as “Bossa Program Port”.
We have closed J3 to power on the board and tried to connect to USB. It is showing blank page.

Attached pic

Hi @skreddy, i’m working on getting a board to test internally… But for the moment, let’s fix the usb driver: “Bossa Program Port” which version of Windows did that?

Grab this driver and force it:



Hi, We are using Windows 10.

Hi @RobertCNelson, Do you have any update ?. Thank you.

Hi @skreddy, sorry just got a Rev 3 board last night. What is the status of D9 LED on your board, mine is “off” neither red/green…


Hi, Same here, D9 LED is off - neither red/green.

Can you please update on this ?

Hi @skreddy, we have a technician validating our boards in stock. It seems your board, and the unit I pulled from testing, did not have a proper firmware (CDC, Segger J-Link) flashed to the SAM3U debugger. This firmware is not available outside of Microchip, so it would have to be sent back to Microchip directly for ‘fixing’.

Microchip requires all returns/rma’s to go thru their portal for quality control: