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

[RK]

what In Circuit Emulator or debugger are you using to try and program the chip? Segger? OpenOCD .. what? 

[cgadgil]

https://www.waveshare.com/wiki/ARM_Debugger

Although it does not mention the nordic microcontroller in the supported microcontroller list, since nordic is cortex M4 i believe it should still work?