Advanced Iris Tracking Software

[kwagyeman]

Only one program can read the serial port at a time. But, once you have the script working in OpenMV IDE... Save the script to the camera, reset the camera, and then open the serial port in another application.

[s-bbrackett]

I guess if you want a simpler answer, I simply want to take data off of the camera and onto visual studios.

[s-bbrackett]

Sorry I didn't see your last post. So, I can write just a print statement and use the IDE terminal with the saved code and it will pickup on VS?

[kwagyeman]

Yes.

Note: On opening the VCP port make the DTR line active. The MicroPython OS will not print data unless this is active.

[s-bbrackett]

Excuse my beginner questions but how to I work the DTS and RTS? I have a RTS function in visual studios but I'm not sure how it works in Micropython.


Thanks

[s-bbrackett]

*DTR

[kwagyeman]

After opening the serial port make sure to set the line. I can give you a snippet of Qt C++ code for example. This is one line of code normally.

[s-bbrackett]

While I don't need the code for Qt, how do I write the code in micropython?

[kwagyeman]

Nothing has to be done on the cam for this. Just print data.

[s-bbrackett]

So no settings, no code? Just save and reset?

[kwagyeman]

Hey man, you may wish to try by doing o_o.

[s-bbrackett]

Hey if you could show me a bit of that Qt code, maybe that might help my issues. A while ago, I sent you a post with the current settings/variables in my VS code. If those could clear anything up, let me know.


Thanks.

[s-bbrackett]

If you understand C#, let me know and I could send you a bit of my code.

[kwagyeman]

Paste it. Use the code tags.

[s-bbrackett]

Here you go:

Code: Select all

using System;
using System.IO.Ports;
using System.ComponentModel;

namespace EyeStuff
{
    class PortDataReceived
    {
        

        public static void Main()
        {
            SerialPort mySerialPort = new SerialPort("COM3");

            mySerialPort.BaudRate = 115200;
            mySerialPort.Parity = Parity.None;
            mySerialPort.StopBits = StopBits.One;
            mySerialPort.DataBits = 8;
            mySerialPort.Handshake = Handshake.None;
            mySerialPort.RtsEnable = true;

            mySerialPort.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);
           
            mySerialPort.Open();

            Console.WriteLine("Press any key to continue...");
            Console.WriteLine();
            Console.ReadKey();
            mySerialPort.Close();
        }

        private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
        {
            SerialPort sp = (SerialPort)sender;
            string indata = sp.ReadExisting();
            Console.WriteLine("Data Received:");
            Console.Write(indata);
        }
    }
}

[kwagyeman]

Okay, is it working?

[s-bbrackett]

The code compiles with no errors and it runs it's "Press any key" part, but it never prints out any data. At this point, I really don't know what the problem could be besides that I forgot something. Please let me know if you have any suggestions.

Thanks

[s-bbrackett]

Never mind I got it working. However, I wanted to say thank you for your help with the DTR. I forgot one line of code within my script and when I fixed it, everything worked fine. Thanks again.

[kwagyeman]

Great to hear!

[s-bbrackett]

Hey I'm back again.
I just wanted to know, if I were to use serial pins to communicate between the two cameras, I would ONLY use pins 4 and 5, right? This is also the simplest way to communicate between the two correct?

Thanks.

[kwagyeman]

Yes, communication is just a serial port between the two devices then. It's full duplex. You can use the struct module to send binary messages and decode them. Or, you can send data as text.

[s-bbrackett]

So I can just use the print function to send text, and then create a statemachine on the other end to receive it?

[s-bbrackett]

I guess the better way to phrase it would be, what's the easiest way to receive data sent by the print command.

[kwagyeman]

No, use this:

import time
from pyb import UART

# Always pass UART 3 for the UART number for your OpenMV Cam.
# The second argument is the UART baud rate. For a more advanced UART control
# example see the BLE-Shield driver.
uart = UART(3, 19200, timeout_char = 1000)

while(True):
uart.write("Hello World!\r")
time.sleep(1000)

uart.write() accepts any formatted string. So, you can use python string formatting there. See all the uart methods: http://docs.openmv.io/library/pyb.UART. ... light=uart

[s-bbrackett]

Awesome! So if that sends strings, how to I receive the strings? Also, don't need to declare the pins anywhere, correct?

[kwagyeman]

UART(3) is fixed to the same I/O pins.

As for receiving data. Please read the UART methods. In general, you want to call any() to see how many bytes are available and then read() that many bytes. If you'd like to see a great example... please see the Pixy Emulation UART script.

[s-bbrackett]

OK so I understand the code, but can I give you an example of how my physical pin system is set up? My system has two openMV cams both plugged into the computer via micro-USB cords. The two cams are then connected with two wires vis pins 4 and 5. Lastly, the camera that sends eye data is disconnected from the openMv IDE while the other is connected. Does this all sound about right?


Thanks again.

[kwagyeman]

Yes, make sure both cameras share grounds and that RX plugs into TX of the other camera and TX plugs into RX of the other camera.

[s-bbrackett]

Thank you, now I have this code as a start but I know its wrong. Could you tell/show me what else I need to add to it.

Code: Select all

uart = UART(3, 19200, timeout_char = 1000)

while(True):
    inData = uart.any()
    print(inData);
    time.sleep(1000)

[kwagyeman]

Code: Select all

uart = UART(3, 19200, timeout_char = 1000)

while(True):
    count = uart.any()
    if count:
    	print(uart.read(count))
    	time.sleep(1000)

[s-bbrackett]

Thank you. So, I have everything all connected via pins 4 and 5, and my system has two connecting ground pins. Then I have one of the cameras plugged into the IDE while the other is disconnected. However, I still am not reading any data on my receiving camera. Do you have any ideas of what could be wrong?

Thanks

[kwagyeman]

The code only prints to the IDE. If you want to send data over the UART you have to call the usrt.write() method. Print sends data back to the PC over USB.

[s-bbrackett]

So I replace all the example code you gave me with usrt?

[s-bbrackett]

If you want I can send you examples of my sending code. The code that's receiving the data is the code that you provided for me.

[kwagyeman]

Okay, I'll take a look.

[s-bbrackett]

So for my sending code I have,

Code: Select all

uart = pyb.UART(3, 115200)

while (True):
    clock.tick()
    # Capture snapshot
    img = sensor.snapshot()
    # Find eyes !
    # Note: Lower scale factor scales-down the image more and detects smaller objects.
    # Higher threshold results in a higher detection rate, with more false positives.
    eyes = img.find_features(eyes_cascade, threshold=0.5, scale=1.5)

    # Find iris
    for e in eyes:
        iris = img.find_eye(e)
        img.draw_rectangle(e)
        img.draw_cross(iris[0], iris[1])
        uart.write("!EYE x:%d, y:%d, w:%d, h:%d" % e)
        uart.write("!IRIS x:%d, y:%d" % iris)

Then for my receiving code I have

Code: Select all

uart = UART(3, 19200, timeout_char = 1000)

#LED
blue_led = LED(3)

while(True):
    count = uart.any()
    if count:
        print(uart.read(count))
        blue_led.on()
        time.sleep(1000)

The pins are then setup as I described before.

Thanks

[s-bbrackett]

Never mind I got it working. However, I was wondering if you could tell me how to pull a string out of a string. MY data is currently being transmitted in the format of

Code: Select all

uart.write("!EYE x:%d, y:%d, w:%d, h:%d" % e)
        uart.write("!IRIS x:%d, y:%d" % iris)

I want to have just the x and y data values at the end, and I am curious as how to go about it. Thank you.

[kwagyeman]

Hi, that would be a general purpose python question. You should Google about how to do that in Python and there's likely a lot of examples.

[jiapei100]

Are you using VSCode to debug OpenMV code?