how to make nrf dongle to enter reset by using software

[Dien Nguyen]

Hi support team,

i'm using nrf dongle 52840 to update firmware for orther device, but somethime i can not able to access to send some command until hard disconnect from usb port or power down system. i can not find any command to make dongle reset by using nrfutil command. Is there anyway to make it reset?
Thanks.

[awneil]

Dien Nguyen said:

somethime i can not able to access to send some command

Dien Nguyen said:

i can not find any command to make dongle reset by using nrfutil command.

If you can't send any commands anyhow, then having a 'Reset' command wouldn't help - because you can't send commands!

[Dien Nguyen]

i mean, i will reset it periodically for example, before I can't connect to dongle

[Hung Bui]

Hi Dien, 

When the dongle gets unresponsive, I don't think it would process any command from PC.

How about implementing WDT (Watch Dog Timer) in the dongle firmware ? It would reset the dongle automatically if there is a crash. 

[Dien Nguyen]

i've thought this before, i suppose that using it too often :)))
it would be better if i can send the reset command than make some change in the firmware

[Dien Nguyen]

i want to know is there any message to make dongle reset, such as nrfjprog --reset, it work with DK board. i see an option -f on nrfutil command for update dfu over ble, is it an option to make dongle reset?

[Hung Bui]

Hi, 

The fundamental difference between the DK and the dongle is that the dongle doesn't have a programmer on board. Any communication for programming with the dongle is via a bootloader. 

So if the dongle is unresponsive it won't be able to do any command because the CPU is blocked. 

If you want to trigger a reset, you can think of connecting a DK (or a programmer) to the dongle ( you need to solder the header on the P1 port). You can use nrfjprog --reset when you connect the programmer/DK to the dongle.

But then it's not much point using a dongle, you can just use the DK.