OpenSDA V2 Release 11.2017 - ISSUE with MKw41Z

[matteolasagni]

Dear All,

we have a custom design based on the MKW41z, which gives us troubles when trying to programming it.

We use a board FRDM-KW41Z as an external programmer, after having appropriately modified the board to program an external MCU. In particular, we have cut the jumpers J14, J13 and J25 of the FRDM-KW41Z and connected them respectively to SWCLK, SWDIO, and Reset of R41Z.

What we notice is that:

- The target MCU supplied with 3V draws 6mA before being programmed. To us, this value looks a bit too high.

- Apparently the target MKW41Z keeps resetting while programming.

- We notice that this issue only occurs when the FRDM-KW41Z is programmed with OpenSDA v2.2 and JLink is used; instead, with DAPLink rev0241 this issue does not occur and the target MCU can be programmed.

In attachment the error generated when trying to program the node via JLink command line interface.

The same  approach works fine when programming the MKw41Z embedded on the same FRDM-KW41Z or the MKw41Z embedded on another MKw41Z.

Our custom board is designed according to the recommendation of NXP, namely we followed the same schematic as indicated for the FRDM-KW41Z.

1. Is there any step that we are overlooking for correctly programming the node?

2. Is it necessary to configure any flag of the MKW41Z before programming it?

Best regards,

Matteo Lasagni

[gerardo_rodriguez]

Hello Matteo,

I was also able to program the KW41 MCU from a FRDM-KW41Z with the OpenSDA JLink debugger interface from another freedom board. This must mean that there is something in your custom hardware that is affecting the OpenSDA JLink interface and the CMSIS-DAP interface is robust enough to work.

Have you checked with an oscilloscope that the SWD_DIO, SWD_CLK and Reset signals are clean and noise free?

My suggestion would be to try with a dedicated external JLink debug probe to see if it has the same behavior as the OpenSDA JLink interface.

About your questions, I believe you are not missing any step. Debugging your custom board should be the same as with the freedom board.

Let me know your findings.

Regards,

Gerardo