Here are the pinouts for the Jetson TX1 and Jetson TX2.
J21 GPIO Header Pinouts – Jetson TX1/TX2
The Jetson TX1 and TX2 share the same carrier board. Here’s some info on the signals on the J21 GPIO Header:
Note: The I2C buss numbers are swapped on the Jetson TX2 versus the Jetson TX1.