Some queries regarding GPIO usage in Jetson Nano

Autonomous Machines Jetson & Embedded Systems Jetson Nano
1

Hello Support,

We need to design our carrier board having need of 30 GPIOs. I would appreciate some queries pertaining to that,

  1. As per pinmux sheet, can we claim pin function to be GPIO for any of pins showing GPIO no; like GPIO_PB.04 under the column “GPIO” of pinmux sheet?

  2. Where do we get details about electrical characteristics of pin like VIH/ VIL, VOH/ VOL, current driving capacity, etc? It seems Jetson Nano product design guide has no details.

  3. Also need details about using GPIO as interrupt, its edge, etc?

Thanks,
jagdish

3

hello jagdish.karamchandani,

please check Accessing GPIOs via “gpio” Device Labels for GPIO numbers.
you should also access TX1 TRM, check Chapter-9.10 for more details of GPIO controller.
thanks

4

Hello Jerry,

Thanks for your response. My query was more about any GPIO as listed in pinmux. The link “accessing GPIO via “gpio” Device Labels” has more about 40-pin expansion header details. Like pinmux has I2S1_XX signals & other such signals, so could such pins be used for GPIO?

Regards,
jagdish

5

hello jagdish.karamchandani,

you may refer to Pinmux spreadsheets for the default board configurations, and also the selections of these pins.
Nano was using dtb file to apply those settings, you may also have an alternative way to disassembler the dtb file into text file for checking.
for example, $ dtc -I dtb -O dts -o output.txt tegra210.dtb

6

Hello Jerry,

I am already referring pinmux spreadsheet, so I just ask that whatever pins are showing GPIO can be configured in GPIO, right? Or there are any exceptions to GPIO configurations to some of pins.

I hope you get my point.

Regards,
jagdish

7

hello jagdish.karamchandani,

yes, you may configure GPIO pins if they’re defined as GPIO in the board configuration.

8

Hello Jerry,

Thanks for confirming, this helped a lot.

Regards,
jagdish