title: How to send data from Jetson nano to Arduino?
body: <p>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 turn on, 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:</p>
  
  <p>Arduino:</p>
  
  <pre><code>char data;
  int LED=13;
  void setup() {
  
  Serial.begin(9600);
  pinMode(LED, OUTPUT);
  digitalWrite(LED, LOW);
  
  }
  
  void loop() {
  
   if (Serial.available() ) { 
    data= Serial.read();
   }
   if(data == 'Y' || data == 'y') {
    digitalWrite(LED, HIGH);
      delay(5000);            
   }
  }
  </code></pre>
  
  <p>Jetson Nano:</p>
  
  <pre><code>#!/usr/bin/python
  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)")
  
  try:
      opt = parser.parse_known_args()[0]
  except:
      print("")
      parser.print_help()
      sys.exit(0)
  
   # load the object detection network
   net = jetson.inference.detectNet(opt.network, sys.argv, opt.threshold)
  
   # create the camera and display
   camera = jetson.utils.gstCamera(opt.width, opt.height, opt.camera)
   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:
      print(detection)
  
  # render the image
  display.RenderOnce(img, width, height)
  
  # update the title bar
  display.SetTitle("{:s} | Network {:.0f} FPS".format(opt.network, net.GetNetworkFPS()))
  
  # print out performance info
  net.PrintProfilerTimes()
  
  
  if (detections &gt; 0):
  
      ser = serial.Serial(port='/dev/ttyUSB0',baudrate=9600)
      time.sleep(2)
      print(ser)
      ser.write('Y')
  </code></pre>