Helios64 has one UEXT (Universal-Extension-Connector) header which exposes 3 serial communication interfaces into a single header:
- RS232 (UART)
Below is the full pinout of the UEXT header:
Be careful with the header polarity when connecting.
SPI & I2C¶
Refer to the respective pages directly:
The UART exposed on the UEXT header is UART Controller 0 from the RK3399 SoC. The primary purpose of this UART is to provide serial communication between SoC and Device connected to the UEXT port.
If you are looking for SoC serial console you should refer to USB-C Console Mode.