Does TX2 have 8 inputs and 16 outputs GPIO?

will use 4 stepper motors,which use GPIO control,a total of 24 gpios are needed.
I know J21 on carrier board which have pin can be used as gpio. I compared the pins with Jetson-TX2-Generic-Customer-pin excel, than i find all pins which can be used as gpio. but When I really control these gpio pins, I can only use some, others will be randomly changed by the system.
Does TX2 have 8 inputs and 16 outputs GPIO which will not be randomly changed by the system?

hello wm18822827507,

there’re several GPIO pin were used by default, you may extract the dts file for examination.
you should also have pinmux customization, please also refer to documentation, Jetson TX2 Pinmux and GPIO Configuration for details.

background:TX2 Jetpack4.2
question:I dont know which node control gpio in dts. and “Jetson TX2 Pinmux and GPIO Configuration” doesn’t help me either,what adderss and value mean in "pinmux. = ", I have no documents to find the address and value.
i maybe need a excel just like “Jetson-TX2-Generic-Customer-Pinmux-Template.xls” which In the how to pinmux customization?
doc.rar (820 KB)

the motor can also be control by pwm. how use hardware pwm on TX2?

background:NVIDIA Jetson TX2 - Jetpack 4.2 [L4T 32.1.0]
questions:, i can’t find “/opt/nvidia/jetson-io/” in my tx2, where it is ?

hello wm18822827507,

that Jetson-IO python script is included in the local host machine.
if you install with SDK manager, it’ll locate as below. $OUT/Linux_for_Tegra/tools/*

i can’t find the path as you saw.
opt@opt-JIAYUES525:~/nvidia/nvidia_sdk/JetPack_4.2_Linux_P3310/Linux_for_Tegra$ ls -lh
total 208K
-rwxr-xr-x 1 opt opt 31K 3月 13 2019
drwxr-xr-x 4 opt opt 4.0K 1月 8 14:17 bootloader
-rwxr-xr-x 1 opt opt 3.2K 3月 13 2019
-rwxr-xr-x 1 opt opt 74K 3月 13 2019
lrwxrwxrwx 1 opt opt 23 3月 13 2019 jetson-tx2-as-4GB.conf -> p2771-0000-as-0888.conf
lrwxrwxrwx 1 opt opt 27 1月 7 16:43 jetson-tx2.conf -> p2771-0000-dsi-hdmi-dp.conf
-rw-r–r-- 1 root root 1.8K 1月 7 16:42 jetson-tx2_conf_back
lrwxrwxrwx 1 opt opt 20 3月 13 2019 jetson-tx2i.conf -> p2771-3489-ucm1.conf
lrwxrwxrwx 1 opt opt 22 3月 13 2019 jetson-xavier.conf -> p2972-0000-devkit.conf
lrwxrwxrwx 1 opt opt 27 3月 13 2019 jetson-xavier-maxn.conf -> p2972-0000-devkit-maxn.conf
lrwxrwxrwx 1 opt opt 30 3月 13 2019 jetson-xavier-slvs-ec.conf -> p2972-0000-devkit-slvs-ec.conf
drwxr-xr-x 4 opt opt 4.0K 3月 13 2019 kernel
-rw-rw-r-- 1 opt opt 4.9K 12月 27 10:41 log.txt
drwxr-xr-x 3 opt opt 4.0K 3月 13 2019 nv_tegra
-rw-r–r-- 1 opt opt 1.9K 3月 13 2019 p2771-0000-as-0888.conf
-rw-r–r-- 1 opt opt 8.5K 3月 13 2019 p2771-0000.conf.common
-rw-r–r-- 1 opt opt 1.8K 3月 13 2019 p2771-0000-devkit.conf
-rw-r–r-- 1 opt opt 1.8K 3月 13 2019 p2771-0000-dsi-hdmi-dp.conf
-rw-r–r-- 1 opt opt 2.3K 3月 13 2019 p2771-3489-ucm1.conf
-rw-r–r-- 1 opt opt 2.2K 3月 13 2019 p2771-3489-ucm2.conf
-rw-r–r-- 1 opt opt 8.2K 3月 13 2019 p2972-0000.conf.common
-rw-r–r-- 1 opt opt 1.7K 3月 13 2019 p2972-0000-devkit.conf
-rw-r–r-- 1 opt opt 1.9K 3月 13 2019 p2972-0000-devkit-maxn.conf
-rw-r–r-- 1 opt opt 1.9K 3月 13 2019 p2972-0000-devkit-slvs-ec.conf
drwxr-xr-x 21 root root 4.0K 12月 26 11:50 rootfs
-rwxr-xr-x 1 opt opt 9.5K 3月 13 2019

hello wm18822827507,

you should note that Jetson‑IO is available with the release of l4t-32.3.1
please access pinmux spreadsheet through download center for customization.

i have access pinmux spreadsheet, i can see the pinmux which can config as gpio in J21. How do I configure it to gpio?

i can control 13 gpio pins now. 11 gpio pins are missing. how can i get more pins in J21?

test 1
tx2 mode: sudo nvpmodel -m 0; sudo /usr/bin/jetson_clocks
Gpio produces square wave frequencies is 71k/hz.

test 2
tx2 mode: sudo nvpmodel -m 3; sudo /usr/bin/jetson_clocks
Gpio produces square wave frequencies is 222k/hz.

questions:I need it to work in mode 0 and the frequency is more than 100k. What’s going on here, How do I fix it?