Debug UART

We didn’t enable the debug UART in the mass production version. However, if our partners need to use the debug UART to port a custom OS or special driver, please refer to the following steps and proceed with caution.

The position of Debug UART

We didn't expose the debug UART on the panel; instead, it is accessible through internal 2.54mm DuPont headers. Please remove the belly cover carefully, and remember to place the O-ring correctly before putting the belly cover back on.

Configure GPIO to enable Debug UART and reflash NRU-230V

If you want to enable the debug UART immediately after the Jetson is powered on, you will need to enable GPIO3_PAC.07 (GPIO12/E10) by updating the the pinmux.

This involves modifying the relevant files and reflashing the Jetson module after applying the pinmux changes. We assume that you have already created an L4T folder with the NRU tarball extracted.

File name: L4T/bootloader/Orin-nru230-gpio-default.dtsi

gpio_main_default: default {
    ...
    gpio-output-low = <
        ...
-       TEGRA234_MAIN_GPIO(AC, 7)
        ...
        >;
        
    gpio-output-high = <
        ...        
+       TEGRA234_MAIN_GPIO(AC, 7)
        ...
        >;
        
};

Connection between NRU-230V and host device

Please prepare USB to TTL converters with 1.8V output to connect the Debug UART pin by following the order mentioned here. Make sure the TX of the Debug UART pin is connected to the RX of the converter.

Use Minicom on the host device to recieve UART data

• Please setup serial port using command: sudo minicom -s , and ensure the setting is as picture shown below.