Communicating with microcontroller via UART issues

Robotics & Edge Computing Jetson & Embedded Systems Jetson Nano
1

Hello,
I am attempting to use the Jetson Nano’s Tx(Pin 8) and Rx(Pin 10) to communicate with a microcontroller operating a 6DOF robotic arm (Amazon.ca).
I have been attempting to follow this tutorial: Jetson Nano - UART - JetsonHacks connecting the Tx of the Nano to the Rx of the controller and vice versa. The microcontroller came with a small manual covering communication protocol for its device. However before I can even being writing instructions to this device I need to figure out how to issue communications via UART, and verify that a signal is actually being sent (as I am concerned I may have shorted the 5V supply pin on the board earlier, and I do not know what damage this would have caused).
I am using this examply code: https://github.com/cheydrick/Canonical-Arduino-Read/blob/master/canonicalarduinoread.c in order to attempt to send a signal to the microcontroller, even though it is incorrect. I have modified it to use ttyTHS1 instead of ttyUSB0. When I connect the microcontroller via UART I do not see any new entries in dmesg or in the list of devices under /dev/.
I am very much a beginner at the hardware aspects of the Jetson Nano but I am familiar with C/C++ programming. This project is an attempt to broaden my understanding of communication protocols, hardware components and electronic theory. Patience and understanding is greatly appreciated.

LeArm user manual.pdf (1.8 MB)

2

hello gstewart9727,

you’ll also need to ensure you don’t have data lose on the serial port.
FYI, we had verification that serial data is being transferred properly without any data loss with execute getty running at background,
you might also refer to Topic 1063027 to enable that.
for example, on Jetson-Nano.

$ sudo /sbin/getty -a ubuntu -L 115200 ttyTHS<port> &
3

Hello JerryChang,
I don’t think data loss is my most immediate issue. I am more concerned about not being able to send a signal using my current method. Running your suggested command yields “[1] 8789”. I am going to attempt to just connect the Nano to a regular arduino to verify that the UART communication is working.