Debugging on NRF52840 Dongle

[Rajendra]

Hi Forum,

I have just purchased nRF52840 Dongle and trying out “Blinky” application from source SDK “nRF5_SDK_for_Thread_and_Zigbee_2.0.0_29775ac\examples\peripheral\blinky”

After compiling and building the program under Eclipse IDE, used “nRF Connect” to program the nRF52840 Dongle. I am successful in downloading and running the program using this way.

 

To have debugging ability, I have soldered 10-pin ARM Cortex JTAG SWD on the nRF52840 Dongle. Made the connections as shown in the pictures attached. Changed delay to 1000 ms in main.c

 

My problem is the downloading and debugging doesn’t work.

Interestingly I get all the messages in Eclipse like J-Link connected, GDB connected, Downloading 1748 bytes @ address 0x00001000 - Verified OK, verification is also OK but the Dongle remains in DFU boot loader mode.

No program is actually downloaded because when I power cycle the Dongle, it runs old Blinky program showing 500ms blink delay. The Eclipse Console log is attached as well for downloading.

Setup Details:

SDK:                   nRF5_SDK_for_Thread_and_Zigbee_2.0.0_29775ac

IDE:                    Eclipse

Dongle:              nRF52840 dongle

Dev board:         nRF52840-Preview-DK

 

Settings on nRF52840-Preview-DK board:   Shorted P22, SW9 set on VDD

Attaching setup images and debug messages herewith.

Fullscreen Debug_problem.txt Download

SEGGER J-Link GDB Server V6.40 Command Line Version

JLinkARM.dll V6.40 (DLL compiled Oct 26 2018 15:06:02)

Command line: -if swd -device nRF52840_xxAA -endian little -speed 1000 -port 2331 -swoport 2332 -telnetport 2333 -vd -ir -localhostonly 1 -singlerun -strict -timeout 0 -nogui
-----GDB Server start settings-----
GDBInit file:                  none
GDB Server Listening port:     2331
SWO raw output listening port: 2332
Terminal I/O port:             2333
Accept remote connection:      localhost only
Generate logfile:              off
Verify download:               on
Init regs on start:            on
Silent mode:                   off
Single run mode:               on
Target connection timeout:     0 ms
------J-Link related settings------
J-Link Host interface:         USB
J-Link script:                 none
J-Link settings file:          none
------Target related settings------
Target device:                 nRF52840_xxAA
Target interface:              SWD
Target interface speed:        1000kHz
Target endian:                 little

Connecting to J-Link...
J-Link is connected.
Firmware: J-Link OB-SAM3U128-V2-NordicSemi compiled Jul 12 2018 11:44:41
Hardware: V1.00
S/N: 683146273
Checking target voltage...
Target voltage: 3.30 V
Listening on TCP/IP port 2331
Connecting to target...Connected to target
Waiting for GDB connection...Connected to 127.0.0.1
Reading all registers
Read 4 bytes @ address 0x00000000 (Data = 0x20000400)
Read 2 bytes @ address 0x00000000 (Data = 0x0400)
Received monitor command: speed 1000
Target interface speed set to 1000 kHz
Received monitor command: clrbp
Received monitor command: reset
Resetting target
Received monitor command: halt
Halting target CPU...
...Target halted (PC = 0x00000998)
Received monitor command: regs
R0 = 00000000, R1 = 00000000, R2 = 00000000, R3 = 00000000
R4 = 00000000, R5 = 00000000, R6 = 00000000, R7 = 00000000
R8 = 00000000, R9 = 00000000, R10= 00000000, R11= 00000000
R12= 00000000, R13= 20000400, MSP= 20000400, PSP= 00000000
R14(LR) = FFFFFFFF, R15(PC) = 00000998
XPSR 01000000, APSR 00000000, EPSR 01000000, IPSR 00000000
CFBP 00000000, CONTROL 00, FAULTMASK 00, BASEPRI 00, PRIMASK 00
Reading all registers
Read 4 bytes @ address 0x00000998 (Data = 0x47184B06)
Read 2 bytes @ address 0x00000998 (Data = 0x4B06)
Received monitor command: speed auto
Select auto target interface speed (1000 kHz)
Received monitor command: flash breakpoints 1
Flash breakpoints enabled
Received monitor command: semihosting enable
Semi-hosting enabled (Handle on BKPT)
Received monitor command: semihosting IOClient 1
Semihosting I/O set to TELNET Client
Received monitor command: SWO DisableTarget 0xFFFFFFFF
SWO disabled successfully.
Received monitor command: SWO EnableTarget 0 0 0x1 0
SWO enabled successfully.
Read 4 bytes @ address 0x00000998 (Data = 0x47184B06)
Read 2 bytes @ address 0x00000998 (Data = 0x4B06)
Downloading 1748 bytes @ address 0x00001000 - Verified OK
Downloading 8 bytes @ address 0x000016D4 - Verified OK
Downloading 112 bytes @ address 0x000016DC - Verified OK
Comparing flash   [....................] Done.
Verifying flash   [....................] Done.
Writing register (PC = 0x    12e0)
Read 4 bytes @ address 0x000012E0 (Data = 0x4A074906)
Read 2 bytes @ address 0x000012E0 (Data = 0x4906)
Received monitor command: clrbp
Received monitor command: reset
Resetting target
Received monitor command: halt
Halting target CPU...
...Target halted (PC = 0x00000998)
Received monitor command: regs
R0 = 00000000, R1 = 00000000, R2 = 00000000, R3 = 00000000
R4 = 00000000, R5 = 00000000, R6 = 00000000, R7 = 00000000
R8 = 00000000, R9 = 00000000, R10= 00000000, R11= 00000000
R12= 00000000, R13= 20000400, MSP= 20000400, PSP= 00000000
R14(LR) = FFFFFFFF, R15(PC) = 00000998
XPSR 01000000, APSR 00000000, EPSR 01000000, IPSR 00000000
CFBP 00000000, CONTROL 00, FAULTMASK 00, BASEPRI 00, PRIMASK 00
Reading all registers
Read 4 bytes @ address 0x00000998 (Data = 0x47184B06)
Read 2 bytes @ address 0x00000998 (Data = 0x4B06)
Starting target CPU...

Any kind of help is most welcome.

Thanks,

Rajendra

[Edvin]

Hello Rajendra,

I believe that you haven't removed the bootloader on the dongle, is that correct?

If you just program an application to the chip while still having the bootloader, the bootloader (which is always run on startup) will not recognize the app as a valid application, and it will stay in bootloader mode waiting for a valid app.

The short answer is: It is not possible to debug on the nRF52840 dongle.

The long answer is:

You can't use the DK to program the dongle, because of the voltage difference between the USB (5V) and the DK (3V). If you have a proper Segger programmer with a level shifter this is possible, but the DK programmer doesn't have this.

That being said, you can program the device with the DK, but this is because the bootloader that is programmed on the Dongle includes a part that changes the power registers before it starts the application. The difficult part is that in order to debug your application you need to either remove or replace the bootloader. If you remove it, or replace it without the power register hack, and then reset the device, you will no longer be able to communicate with it using the DK's programmer, and your dongle is bricked until you get hold of a proper segger programmer.

Basically, if you do: "nrfjprog --eraseall && nrfjprog --reset", it is bricked.

We are currently in the making of a guide/blog post that describes how you can use your dongle for developing, but it is not finished yet. I am not quite sure what the blog post will contain, and the guy writing it is out of office this week, so I can't ask him.

We also state that the dongle is not a development kit. If you want to develop on the nRF52840, I really really recommend you to go with the nRF52840 DK.

Best regards,

Edvin

[masterLee]

Hi,  I would like to see this  guide/blog when you finish it since I had similar issues.

I managed to find a solution though, with the help of SB47 next to debug-out connector.

When I couple SB47 the SWD cable I use takes Voltage and the nRF Dongle has power from the cable.

So USB of the dongle is not needed to power the dongle. So you can program the bootloader again in the dongle and thus enabling the USB power of it . Then you can use the nRF connect as before.

Please when you complete the guide send a reply in this post with the link so we can be notified.

Thank you for your time.

[Edvin]

https://devzone.nordicsemi.com/tutorials/b/getting-started/posts/nrf52840-dongle-programming-tutorial