1.2 KiB
1.2 KiB
Helios64 has one UEXT (Universal-Extension-Connector) header which exposes 3 serial communication interfaces into a single header:
- I2C
- SPI
- RS232 (UART)
Pinout Table
Below is the full pinout of the UEXT header:
| PIN | Port | Remarks |
|---|---|---|
| 1 | 3.3V | |
| 2 | GND | |
| 3 | TXD (UART) | |
| 4 | RXD (UART) | |
| 5 | SCL (I2C) | |
| 6 | SDA (I2C) | |
| 7 | MISO (SPI) | |
| 8 | MOSI (SPI) | |
| 9 | SCK (SPI) | |
| 10 | SSEL (SPI) |
!!! Warning Be careful with the header polarity when connecting.
SPI & I2C
Refer to the respective pages directly:
RS232 (UART)
The UART bus exposed on the UEXT header is the same than the RK3399 SoC serial console exposed on the USB Type-C. There is no dedicated UART bus on the UEXT connector. The intention is to allow user to connect to SoC serial console by another way than the USB-to-Serial bridge.
!!! Important If you connect some modules which might require dedicated serial UART line to the SoC, this module will not operate properly.