[Hardware Design Question : ]How to design a valid PINRESET for nrf52833 ?

[ld2000]

Dear Nodic friends,

We use nrf52833 to design a BLE control box with USB DFU function.

During USB DFU, DFU Trigger Library will reset nrf52833, so we should connect a GPIO to RESET pin -- P0.18 .

My question:

1) In Nordic reference design in PCA10059 (nrf52840 USB dongle), four GPIOs connected to RESET pin, P0.19 and P0.21 and P0.23 and P0.25. 

Why did you connect four GPIOs to RESET pin ? 

2) In our nrf52833 design, we will connect only one GPIO P0.10 to RESET pin. Is it OK ? 

NFC function is deleted in our production.

Thanks. 

[JONATHAN LL]

Hi,

2) In our nrf52833 design, we will connect only one GPIO P0.10 to RESET pin. Is it OK ? 

 Connecting only one other GPIO is OK to control reset pin P0.18 if that is wat you want.


But, only one pin actually works as reset pin on the nrf52833, pin 18. https://infocenter.nordicsemi.com/topic/ps_nrf52833/ref_circuitry.html?cp=4_1_0_6_2_5#unique_1429698681, https://infocenter.nordicsemi.com/topic/ps_nrf52833/pin.html?cp=4_1_0_6_0. 

1) In Nordic reference design in PCA10059 (nrf52840 USB dongle), four GPIOs connected to RESET pin, P0.19 and P0.21 and P0.23 and P0.25. 

 Our HW designer is currently on vacation so i don't have the answer. If you want i can get back to you when i know the reason why. 

Regards,
Jonathan

[ld2000]

Thanks Jonathan for your confirmation.

If you get the reason of my question 1, you may send it to my email. 

Thanks  a lot.