How do I run the SPE demo code on TX2


I flashed the SPE binary to the TX2 with GTE (generic timestamping engine) enabled. How do I verify that the flash is successful? The instruction says it’s gonna print stuff after I short pin 17 and pin 15. Where is this message gonna be printed at?

Thanks in advance!

Hello, hengruiz:
You need not short pins for timer app test. The message SPE firmware prints will output to UARTG (serial@c290000).
If you made the carrier board yourself, just export Tx/Rx of that UART for SPE debug port.
If you are using NV Jetson TX2, you may have to fly wires to export those 2 pins.


Thanks for your reply. I’m actually trying to run the GPIO/GTE app, which needs to short pin 15 and pin 17 according to the instruction. Do you think it is possible to get the debug print from the TX2 itself, instead of exporting tx/rx and reading from an external device?

Thank you

Hello, Hengruiz:
Shorting pin 15 and 17 in J26 as described in doc/ is just to test GPIO and connect the GPIO input pin to output pin and trigger the interrupt/check the GPIO functions. It has nothing to do with debug print.

It’s better to wire a UART port with TX/RX for further development.


Hi ChenJian,

I’m trying to get this working on Xavier now.

Do you mean the UARTG port as described in the doc? Or the UARTC port used by kernel?
The gpio doc also says Short GPIO pins of the 40 pin header J30 pin 16 and pin 32, this should print out “GPIO input irq triggered” message since pin 16 is configured as OUT which drives the pin 32 which is configured as INPUT and also has interrupt enabled.. Is this print statement gonna be print directly to the UART debug port?

The doc also mentions the TCU for debug. I connected my host machine with the Xavier and open up a minicom port to the SPE device, but nothing gets printed. Do I need to configure anything to get it printing to the TCU port?

Thank you so much

Hello, Hengruiz:
For Xavier, you can connect USB for debug port (refer to for details.). Xavier uses UARTC as physical port for debug. (TCU: Tegra Combined UART)
SPE FW uart-app.c initializes/configures/tests UARTG in Xavier.

When those module test patterns running, some messages will be output to debug UART port.