nRF52840 mini dongle programming

[astella]

To the kind attention of Nordic support team,

I'm considering to get started manufacturing mini dongle nRF52840 based as in https://devzone.nordicsemi.com/f/nordic-q-a/48568/nrf52840-mini-dongle/193001#193001.

We already had such a mini dongle using your nRF24. As it is stated in nRF24 product specification, it comes with a pre-programmed USB bootloader in the on-chip flash memory. As you said in https://devzone.nordicsemi.com/nordic/short-range-guides/b/getting-started/posts/nrf52840-dongle-programming-tutorial The nRF52840 Dongle is shipped with an Open USB bootloader which allows it to be programmed without the need for a debugger. Sorry I didn't get if all nRF52840 comes pre-programmed with it? Should it the case may you please point me to the right documentation? So, my question is, in case they don't come pre-programmed with the USB bootloader, do we have to buy special lots? Or do we have to always include SWD access in order to have our devices programmed? Why, if it is the case, this difference in respect to the nRF24?

Thank you very much for your kindness

[Einar Thorsrud]

Hi,

Sorry I didn't get if all nRF52840 comes pre-programmed with it?

No. The nRF52840 Dongle is a separate product, and this is shipped with a USB bootloader in flash. However, the nRF52840 chip, in general, is shipped with an empty flash.

do we have to always include SWD access in order to have our devices programmed?

Yes. You would typically program the devices in production, often at the same time as you do production testing. You can also program the chips before they are mounted on the PCB, potentially ordering programming from another company.

Why, if it is the case, this difference in respect to the nRF24?

You are right that the nRF24L01+ is shipped with a USB bootloader. This is not done for other product though, and I cannot comment on why this is. It is not a common request, though.

[astella]

Thank you everything is clear