Debugging external nRF51422

[swoud]

Hi,

I am programming and debugging an external customised board by following the DK manual and the below link: electronut.in/.../

I use the interface P20 instead of P19, and wire the four signals (VTG, GND_Detect, SWDIO and SWDCLK) to the external board. I think the programming should be fine because I can see the programming processing bar. However, I cannot debug this external board. As mentioned in the manual of DK, the DK should bypass the internal chip and debug the external one if the external one is powered on, but from what I could see, the DK is still debugging the internal chip.

Could you please give me some suggestions? Thanks

[Update]

I checked again about this problem, and I do the following efforts:

1. I first upload a script into the chip, so the chip will print characters on the serial port.

2. I connect the VDD and SH_VTG of P20, GND and SH_GND_DETECT of P20 together (as the photo show below, without connecting the external board).

3. Under this configuration, I suppose the DK should bypass the internal chip. However, it does not. After powering on the DK, the serial port is still doing the printing.

4. Under this configuration, I tried to do the programming, but it is not successful - meaning the programming is directed to the external chip.

Would you please give me some suggestions?

[RK]

I have no more ideas and your explainaion about the serial port was too contorted to understand. I am however telling you that if the debugger is connected during programming then it's connected during debugging, they are one and the same thing. It's either connected, or it's not connected.

Try using JLink from the command line to go read the FICR where the unique MAC address of the chip is, that will tell you which chip you are actually talking to

[swoud]

Hi, what confuses me is that, when the pin1 of P19 is supplied with high voltage while pin10 is connected to the GND, the DK should bypass the internal chip, however, it doesn't. is there any reason for this?

[RK]

No there is no reason for this - it works - therefore either you have not connected it properly or you have misidentified which board you are connected to and it has in fact bypassed it, or you blew something up whilst trying it out .

Again - use the JLink command line to read the FICR on the chip to work out what you are actually connected to in each case.

[swoud]

Hi, thanks for your reply. I am sorry but I know quite little about software part. Could you please guide me how to connect to the target chip via JLink command line? Thanks a lot.

[swoud]

Hi, could you please refer to my update and give me some suggestions?