User will be concerned by this note in the following cases:
- migration from KW35/36_HVQFN48 Wettable Flank package version to KW37/38/39
- Flashloader is used via UART0 interface
So, KW35/36_HVQFN48 Wettable Flank package version and KW37/38/39 are pin to pin compatible.
In order to keep more flexibility on KW37/38/39 pins used for the flashloader have been updated for UART0.
KW35/36 UART0 pin: PTC2_UART0_RX, PTC18_UART0_RX
KW37/38/39 UART0 pin: PTC6_UART0_RX, PTC7_UART0_RX (PTC18 is kept for SPI only)
The flashloader is programmed in the NXP factory to allow the user to dowload its own code.
To know more on Flashloader: https://community.nxp.com/docs/DOC-341224
To know more on KW37/38/39: KW39/38/37 32-bit Bluetooth 5.0 Long-Range (please refer to Reference MAnual for Flasloader interface listing)
User migrating from KW35/36_HVQFN48 Wettable Flank package version to KW37/38/39 and using flashloader via follwing interfaces are not concerned: I2C, SPI or CAN