how does the nrf52832 decide to enter the swd mode?

[cgadgil]

hi

my question is really basic, but i am not able to find an answer anywhere else. I am trying to program the nordic using its SWDIO and SWCLK pins and am stuck as i get " emulator not found" error. I am wondering what the problem could be. How does the nrf52832 detect a swd programmer connected and decide to enter the debug mode as against running its existing code if any? 

is a reset or some specific signal on any other pin necessary?

I have used the nrf51822 before and i only connected SWDIO, SWCLK, VCC and GND and everything worked well. but with the nrf52832 i am having issues programming the IC.

thanks in advance for the answer

[Håkon Alseth]

For the specific debugger that you're using, it seems that it has limited support according to this page: https://www.waveshare.com/arm-debugger.htm

It mentions that this only works with the nRF51822 board. I suspect that the manufacturer does not support other devices with this specific programmer, but I would recommend contacting them to double check.

Best regards,

Håkon

[cgadgil]

thanks!

yes it seems so.. i will check with the manufacturer. However i would still want to know the answer to my question "How does the nrf52832 detect a swd programmer connected and decide to enter the debug mode as against running its existing code if any? "

because i am not finding sufficient documentation on the reset process from hardware + firmware perspective at one place

[Håkon Alseth]

Hi,

 

The nRF51 has mux'ed the nRESET pin with the SWDIO pin, so the setup there is a bit different to other Cortex M-family devices. The nRF52832 has dedicated SWDIO/SWDCLK pins, thus it uses the standardized ARM DAP to enable the "debugger interface" (DIF). More info can be found in one of our white papers:

http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.whitepapers/dita/whitepapers/nwp_027/intro.html?cp=11_4

Cheers,

Håkon

[cgadgil]

thanks

reading the following gave a clearer picture

http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0314h/Babdadfc.html

To update on the programming issue, i tried another set of custom PCB with nrf52832 with same result. The device is initially detected, softdevice  is programmed and while downloading the application i get an error. After this happens the my laptop refuses to detect the device. Any subsequent power up cycles and effort to connect to the device fail.

I am afraid my programmer may be damaging my device in some way.

[cgadgil]

nrfjprog --eraseall --log
nrfjprog version 9.7.3
--------------------------------------------------------------------------------
nRF_open_dll
. nRFXX_open_dll
. . nRFXX_dll_version
nRF_enum_emu_snr
. nRFXX_enum_emu_snr
nRF_enum_emu_snr
. nRFXX_enum_emu_snr
nRF_connect_to_emu_with_snr
. nRFXX_connect_to_emu_with_snr
. . nRFXX_is_connected_to_emu
. . nRFXX_connect_to_emu_without_snr
. . . nRFXX_is_connected_to_emu
. . . nRFXX_enum_emu_snr
. . nRFXX_connect_to_emu_without_snr:	JLink:	 Firmware: J-Link ARM-OB STM32 compiled Aug 22 2012 19:52:04
. . nRFXX_connect_to_emu_without_snr:	JLink:	 Hardware: V7.00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 S/N: 20151216
. . nRFXX_connect_to_emu_without_snr:	JLink:	 Feature(s): RDI,FlashDL,FlashBP,JFlash,GDBFull
. . nRFXX_connect_to_emu_without_snr:	JLink:	 TELNET listener socket opened on port 19021
. . nRFXX_connect_to_emu_without_snr:	JLink:	WEBSRV  Starting webserver
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0031ms, 0039ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	WEBSRV Webserver running on local port 19080
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0034ms, 0042ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns O.K.
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0037ms, 0045ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_GetHWStatus(...)
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0004ms, 0053ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_ExecCommand("Device = NRF52832_xxAA", ...). 
. . nRFXX_connect_to_emu_without_snr:	JLink:	C:\Program Files (x86)\SEGGER\JLink_V622g\JLinkDevices.xml evaluated successfully.
. . nRFXX_connect_to_emu_without_snr:	JLink:	Device "NRF52832_XXAA" selected.
. . nRFXX_connect_to_emu_without_snr:	JLink:	Device "NRF52832_XXAA" selected.
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0237ms, 0293ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_ExecCommand("SetRestartOnClose = 0", ...). 
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x01
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0001ms, 0297ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_ExecCommand("DisableFlashDL", ...). 
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0001ms, 0300ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_ExecCommand("SetDbgPowerDownOnClose = 1", ...). 
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x01
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0001ms, 0303ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_ExecCommand("ExcludeFlashCacheRange 0x0-0xFFFFFFFF", ...). 
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0001ms, 0306ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_TIF_Select(JLINKARM_TIF_SWD)
. . nRFXX_connect_to_emu_without_snr:	JLink:	  returns 0x00
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0003ms, 0310ms total)  
. . nRFXX_connect_to_emu_without_snr:	JLink:	JLINK_SetSpeed(2000)
. . nRFXX_connect_to_emu_without_snr:	JLink:	 (0002ms, 0313ms total)  
nRF_read_connected_emu_snr
. nRFXX_read_connected_emu_snr
. . nRFXX_is_connected_to_emu
. . nRFXX_is_connected_to_emu:	JLink:	JLINK_IsOpen()
. . nRFXX_is_connected_to_emu:	JLink:	  returns 0x01
. . nRFXX_is_connected_to_emu:	JLink:	 (0002ms, 0316ms total)  
nRF_read_device_family
. nRFXX_read_device_family
. . nRFXX_is_connected_to_emu
. . nRFXX_is_connected_to_emu:	JLink:	JLINK_IsOpen()
. . nRFXX_is_connected_to_emu:	JLink:	  returns 0x01
. . nRFXX_is_connected_to_emu:	JLink:	 (0003ms, 0320ms total)  
. . nRFXX_read_access_port_register
. . . nRFXX_coresight_configure
. . . nRFXX_coresight_configure:	JLink:	JLINK_CORESIGHT_Configure()
. . . nRFXX_coresight_configure:	JLink:	 >0x10B TIF>
. . . nRFXX_coresight_configure:	JLink:	 >0x10F TIF>
. . . nRFXX_coresight_configure:	JLink:	 >0x0D TIF>
. . . nRFXX_coresight_configure:	JLink:	 >0x0D TIF>
. . . nRFXX_coresight_configure:	JLink:	  returns 0
. . . nRFXX_coresight_configure:	JLink:	 (0009ms, 0330ms total)  
. . . nRFXX_power_debug_and_system_regions
. . . . nRFXX_write_debug_port_register
. . . . nRFXX_write_debug_port_register:	JLink:	JLINK_CORESIGHT_WriteAPDPReg(DP reg 0x02, 0x00000000)
. . . . nRFXX_write_debug_port_register:	JLink:	 >0x0D TIF>
. . . . nRFXX_write_debug_port_register:	JLink:	  returns -1
. . . . nRFXX_write_debug_port_register:	JLink:	 (0004ms, 0336ms total)  
. . . . nRFXX_write_debug_port_register:	JLinkARM.dll CORESIGHT_WriteAPDPReg returned error -1.

. . . nRFXX_power_debug_and_system_regions:	JLinkARM.dll CORESIGHT_WriteAPDPReg returned error -102.

nRF_close_dll
. nRFXX_close_dll
. . nRFXX_is_connected_to_emu
. . nRFXX_is_connected_to_emu:	JLink:	JLINK_IsOpen()
. . nRFXX_is_connected_to_emu:	JLink:	  returns 0x01
. . nRFXX_is_connected_to_emu:	JLink:	 (0002ms, 0339ms total)  
. . nRFXX_disconnect_from_emu
. . nRFXX_disconnect_from_emu:	JLink:	JLINK_Close()