You've got UART access to an embedded device. Maybe you soldered wires to test pads, maybe the debug header was exposed. Either way, you have a shell - but UART is painful: Slow (115200 baud = ~2-3 KB ...

This demo shows how to configure and use the UART driver from the Real-Time Drivers (RTD / MCAL) package on the FRDM-A-S32K344 microcontroller using S32 Design Studio. The example demonstrates UART ...