How can I tell what GPIO pins are available for use as just regular gpio (write a 1 or a 0) on the J21 header?
What is “cat /sys/kernel/debug/gpio” telling me? And how do tell what is already set up as a gpio?
Please don’t point me to this: Jetson/Tutorials/GPIO - eLinux.org as it hasn’t been very helpful for me. The output for the “cat /sys/kernel/debug/gpio” command isn’t shown in that tutorial so I have no clue what to look for. Also, I don’t know how to find out the gpio number used in software and how that links to the external header pin.
All I want is to turn on an external LED or two and sense button input on a button or two in a polling fashion. Hopefully I can stay in user space for all of this.
Like I said, I’m new to embedded Linux so, if possible, be as detailed as possible.
Hi, I just got my Tk1 last night, looking t do the same thing, also I am brand new to embedded Linux. Finding bits of info here and there; This is something anyway:
Are you talking about the TK1 datasheet? I couldn’t find the table you reference in the TX1 datasheet. Also, in Table 14 in the TK1 datasheet, I don’t understand how the pins listed map to actual code.