Sending Data from Jetson Nnao to Arduino

Hello, I’m trying to connect NVIDIA Jetson Nano through serial communication with Arduino Uno via USB, so when my camera, connected to the jetson nano, detect an object the LED start to flash, but it’s not working. I think my arduino doesn’t receive any data from the jetson. If someone can help me with suggestions, or the answer that would be great. Here is my code for arduino and for jetson nano:


char data;
int LED=13;
void setup() {

pinMode(LED, OUTPUT);
digitalWrite(LED, LOW);


void loop() {

 if (Serial.available() ) { 
 if(data == 'Y' || data == 'y') {
  digitalWrite(LED, HIGH);

Jetson Nano:

import jetson.inference
import jetson.utils
import time
import serial
import argparse
import sys

# configure the serial connections (the parameters differs on the device you are connecting to)
ser = serial.Serial(port='/dev/ttyUSB0',baudrate=9600)

# parse the command line
parser = argparse.ArgumentParser(description="Locate objects in a live camera stream using an object detection DNN.", formatter_class=argparse.RawTextHelpFormatter,epilog=jetson.inference.detectNet.Usage())
parser.add_argument("--network", type=str, default="ssd-mobilenet-v2", help="pre-trained model to load (see below for options)")
parser.add_argument("--overlay", type=str, default="box,labels,conf", help="detection overlay flags (e.g. --overlay=box,labels,conf)\nvalid combinations are:  'box', 'labels', 'conf', 'none'")
parser.add_argument("--threshold", type=float, default=0.5, help="minimum detection threshold to use") 
parser.add_argument("--camera", type=str, default="0", help="index of the MIPI CSI camera to use (e.g. CSI camera 0)\nor for VL42 cameras, the /dev/video device to use.\nby default, MIPI CSI camera 0 will be used.")
parser.add_argument("--width", type=int, default=1280, help="desired width of camera stream (default is 1280 pixels)")
parser.add_argument("--height", type=int, default=720, help="desired height of camera stream (default is 720 pixels)")

    opt = parser.parse_known_args()[0]

 # load the object detection network
 net = jetson.inference.detectNet(, sys.argv, opt.threshold)

 # create the camera and display
 camera = jetson.utils.gstCamera(opt.width, opt.height,
 display = jetson.utils.glDisplay()

# process frames until user exits
while display.IsOpen():
# capture the image
img, width, height = camera.CaptureRGBA()

# detect objects in the image (with overlay)
detections = net.Detect(img, width, height, opt.overlay)

# print the detections
print("detected {:d} objects in image".format(len(detections)))

for detection in detections:

# render the image
display.RenderOnce(img, width, height)

# update the title bar
display.SetTitle("{:s} | Network {:.0f} FPS".format(, net.GetNetworkFPS()))

# print out performance info

if (detections > 0):

    ser = serial.Serial(port='/dev/ttyUSB0',baudrate=9600)

I don’t know anything about the particular Arduino board, but do you have file “/dev/ttyUSB0”? Possibly the serial UART already has a driver for this, in which case the file will be present, but otherwise you might need to add the driver.

Quick Question! Where can the serial module used in this python script be downloaded from? I downloaded pyserial from github but ser = pyserial.Serial(…) doesn’t work for me. It recognizes pyserial but does not recognize Serial. Thanks!