NRF52840-QFAA not able run blinky

RE: NRF52840-QFAA not able run blinky

Dany — Tue, 25 Mar 2025 09:28:35 GMT

hi, I already re-soldering all component on my board, configure for it to work with internal 32.768kHz crystal and it already worked. Thank you so much for your support

RE: NRF52840-QFAA not able run blinky

Håkon Alseth — Thu, 20 Mar 2025 11:22:04 GMT

Hi,

Are those pins already in use for UART? If yes, you cannot control them manually, as the pins are claimed by the peripheral when UARTE is enabled.

Have you tried debugging your firmware to see if it is stuck somewhere?

Kind regards,

Håkon

RE: NRF52840-QFAA not able run blinky

Dany — Thu, 20 Mar 2025 05:02:34 GMT

I connect LED cathode to this pins, and Anode to Vnrf

RE: NRF52840-QFAA not able run blinky

Håkon Alseth — Wed, 19 Mar 2025 08:42:43 GMT

Where have you connected these LEDs? Please note that a GPIO is not able to source in the range of 10-20 mA, so you will need a buffer circuit (transistor) to turn on these LEDs.

Also, try to enter debug mode to see if your code runs.

Kind regards,

Håkon

RE: NRF52840-QFAA not able run blinky

Dany — Wed, 19 Mar 2025 05:33:51 GMT

Here is UI for Programmer by NRF Connect SDK when I flash code to the chip, and read back, it's look not same, do not have green area compare to the hex file

I also measure VDEC46 = 1.27V and VDEC1=1.1V

RE: NRF52840-QFAA not able run blinky

Dany — Wed, 19 Mar 2025 05:26:25 GMT

Hi,

Thank you for your reply

Yep I find my board do not have 32k Crystal so I already put this config to the defconf file, but it's still not blink

I use multimeter and measure the voltage of the LED pin is fix 1.15V, not toggle.

And I still stuck there for some days

RE: NRF52840-QFAA not able run blinky

Håkon Alseth — Tue, 18 Mar 2025 16:03:21 GMT

Hi,

It looks like your design does not have a external 32k.

Could you try enabling the internal 32k RC oscillator?

CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y

Kind regards,

Håkon

RE: NRF52840-QFAA not able run blinky

Dany — Tue, 18 Mar 2025 15:48:20 GMT

the sdk and device tree for custom board information

RE: NRF52840-QFAA not able run blinky

Dany — Tue, 18 Mar 2025 15:42:46 GMT

this is the PCB image