Hi asthra,
I am using FRDM-K20D50M(SCH Rev D) with KDS3.2.0.
Refer the Typical Usage of Component Serial_LDD.

After input 'e' at UART2_RX(PTD2 Pin8 J2), I can receive the 'Hello world' from UART2_TX(PTD3 Pin10 J2).

I have attached the test project.
Best Regards,
Robin
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