KW45 First Time Programming

[cnew01]

I am trying to program a custom KW45-based PCB for the first time. I tried using MCUXpresso. The J-Link could upload my program over SWD but when I tried entering debug mode the board halts at address 0x14816fdc. Further research has shown that the NBU for the Bluetooth coprocessor needs to be uploaded. I've tried AN13838, but my board cannot be discovered over UART. I've been looking into AN14003, but it's information is out of date with regards to the current SPSDK. What do I do?

[luis_maravilla]

Hello

The memory address you mention refers to ROM-Boot [Table 16 KW45 Reference Manual], On KW45, only boot ROM has access to the NBU flash,

For more information about ROM boot process flow please refer to AN14003 Figure 2

As you are using a KW45 chip from fabric for your custom PCB; Could you help us confirm if your KW45 chip from fabric was already fuse burned as the process described in AN14003?

And if there was already fuse burned, Could you confirm if the default KW45B41Z-EVK Keys [SBKDK and RoTKTH] described in Chapter 5.2.1 [AN14003] were used? Or you use custom generated keys for the board.

Also for confirmation, Have you done an updating NBU before on the chip?

Best Regards

Luis

[cnew01]

The fuses had not been burned yet, the KW45 is from fabric. Updating the NBU on the chip has not been done before.

[cnew01]

I will clarify that LPUART0 TX and RX pins are accessible on this custom board through a header.