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.
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.