how to connect to nRF5340 from smart phone?

[woff]

Hello ,I just buy nRF5340 pdk and look at user guide https://infocenter.nordicsemi.com/pdf/getting_started_NCS_nRF53.pdf.
I installed nRF Connect in my PC, and flash HEART HEX to nRF5340.
I installed Nordic nRF Toolbox app in my smart phone for Android OS,
but my phone can't scan nRF5340 PDK devices.
My phone is samsung A8 and HTC U11+ for Android 7.1 .
Please help me, thank you.

[woff]

2020-08-16T15:41:47.896Z INFO Using nrfjprog to communicate with target
2020-08-16T15:41:47.899Z ERROR Could not fetch memory size of target devkit: Error: Error occured when get library info. Errorcode: CouldNotOpenDevice (0x4)
Lowlevel error: INVALID_OPERATION (fffffffe)

[Nikosant03]

I recommend you to follow the Running a first test and Programming an application of Getting started with nRF Connect SDK (nRF53 Series)

Also try to flash your pdk with an example that does not require softdevice.

[woff]

I try to Running a first test and Programming an application of Getting started with nRF Connect SDK (nRF53 Series) many time.

But I can't flash hex to nRF5340 anytime now.

Because I flash wrong hex before.

help me

[Nikosant03]

You're using the programmer (from nRF Connect for Desktop) to flash your board isn't it? Did you try the "Erase all" and then the "Read" to verify that the memory is empty? 

Did you try an example that do not require softdevice?

Also check this post

[woff]

I cut a pic below. 

It can't do anymore

because button is false.

logs(

2020-08-17T06:52:37.909Z INFO Application data folder: C:\Users\Administrator\AppData\Roaming\nrfconnect\pc-nrfconnect-programmer
2020-08-17T06:52:37.985Z DEBUG App pc-nrfconnect-programmer v1.4.4 official
2020-08-17T06:52:37.985Z DEBUG App path: C:\Users\Administrator\.nrfconnect-apps\node_modules\pc-nrfconnect-programmer
2020-08-17T06:52:37.985Z DEBUG nRFConnect 3.4.2 is supported by the app (^3.3.0)
2020-08-17T06:52:37.985Z DEBUG nRFConnect path: C:\Users\Administrator\AppData\Local\Programs\nrfconnect\resources\app.asar
2020-08-17T06:52:37.985Z DEBUG HomeDir: C:\Users\Administrator
2020-08-17T06:52:37.985Z DEBUG TmpDir: C:\Users\ADMINI~1\AppData\Local\Temp
2020-08-17T06:52:38.004Z INFO Using nrfjprog library 10.9.0, pc-nrfjprog-js 1.7.3
2020-08-17T06:52:38.007Z VERBOSE Could not fetch serial number for serial port at COM1
2020-08-17T06:52:39.796Z INFO Using nrfjprog to communicate with target
2020-08-17T06:52:40.057Z INFO Using J-Link Software version 6.80
2020-08-17T06:52:40.763Z INFO Segger serial: 960119975
2020-08-17T06:52:40.763Z INFO Segger speed: 2000 kHz
2020-08-17T06:52:40.763Z INFO Segger version: J-Link OB-K22-NordicSemi compiled Jan 21 2020 17:33:01
2020-08-17T06:52:40.766Z INFO Core probed: 960119975.
2020-08-17T06:52:40.766Z INFO Core RAM: 512KiB.
2020-08-17T06:52:40.766Z INFO Core ROM: 1024KiB in pages of 4KiB.
2020-08-17T06:52:41.751Z ERROR Error when closing nrfjprog: Error: Error occured when close opened device. Errorcode: CouldNotResetDevice (0x5)
Lowlevel error: CANNOT_CONNECT (fffffff5)

2020-08-17T06:52:41.751Z INFO Model: NRF5340_xxAA_ENGA.
2020-08-17T06:52:41.754Z ERROR Error when getting device info: Error: Error: Error occured when open device long term. Errorcode: CouldNotOpenDevice (0x4)
Lowlevel error: INVALID_OPERATION (fffffffe)

2020-08-17T06:52:41.757Z ERROR Error when closing nrfjprog: Error: Error occured when close opened device. Errorcode: CouldNotOpenDevice (0x4)
Lowlevel error: INVALID_OPERATION (fffffffe)

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