Read the data of the NFC reader connected to Raspberry Pi 3 with Python and send it to openFrameworks with OSC

1. Overview

Continuing from the previous article (Running openFrameworks sample program on Raspberry Pi 3 --Qiita), replace Mac for exhibition with Raspberry Pi It is an attempt to do so.

Last time, I installed oF on Raspberry Pi and ran the sample program, so this time I will connect the NFC reader to Raspberry Pi and send the NFC data read from the python program to openFrameworks with OSC.

2. Working environment

• Raspberry Pi 3 + 2016-09-23-raspbian-jessie
• RFID-RC522 Amazon Search: RC522

3. Reference site

1. How to connect NFC reader / writer RFID-RC522 of SPI communication method to Raspberry Pi 3 Model B and read NFC tag (How to connect NXP MFRC522 RFID reader / writer to Raspberry Pi 3 and read NFC card without contact)
2. mxgxw/MFRC522-python: A small class to interface with the NFC reader Module MFRC522
3. Python OSC (pyOSC) | Android Days
4. pyOSC 0.3.5b-5294 : Python Package Index
5. Realize ofxFaceTracker with Raspberry Pi2 --Take ’s diary

4. Use NFC reader on Raspberry Pi 3

I made it possible to use the NFC reader by relying on the reference site 1. The program I ran is Read.py on reference site 2. Since it was as per the reference site, it is omitted.

When I first tried it, I ran the program and it didn't respond to NFC tags. The site said that I had to disable the Device Tree, but I couldn't find the Device Tree in the Advanced Option even after `sudo raspi-config`.

I wasn't sure, but I reinstalled Raspbian and it got better. I bought a micro SD card with Raspbian 2016-02-26 pre-installed, but the pre-installed one may not have been good.

5. Install pyOSC

I used osc to bring the python sample program run in 4. to openFrameworks. I thought it would be nice if I could read the NFC reader directly from oF, but I didn't know what to do, so I chose this method.

I tried pyOSC while looking at the reference site 3. (Python OSC (pyOSC) | Android Days).

Install pyOSC

git clone https://gitorious.org/pyosc/devel.git
cd devel
sudo python setup.py install

Failure

Reference site 3. I tried the sample program written in, but it didn't work.

git clone https://github.com/conanxin/Arduino-Meets-Blender-OSC.git

Start up two terminals and try running the sample program.

terminal1

cd Arduino-Meets-Blender-OSC/pyOSC_examples
python basic_receive.py

terminal2

cd Arduino-Meets-Blender-OSC/pyOSC_examples
python basic_send.py

When I ran send.py, I got the following error.

terminal2

Traceback (most recent call last):
  File "basic_send.py", line 28, in <module>
    client.sendto(msg, ('127.0.0.1', 2014)) # note that the second arg is a tupple and not two arguments
  File "/usr/local/lib/python2.7/dist-packages/OSC.py", line 1174, in sendto
    ret = select.select([],[self._fd], [], timeout)
AttributeError: 'OSCClient' object has no attribute '_fd'

I just didn't understand.

success

Take a moment and try another sample. Run the sample that was in the develop folder where you downloaded pyOSC.

terminal1

cd devel/examples
python knect-rcv.py

terminal2

cd devel/examples
python knect-snd.py

When I executed knect-snd.py, the following was displayed on the screen of knect-rcv.py.

terminal1

('Now do something with', 'user1', 3.0, 1.0, -1.0)
('Now do something with', 'user2', 4.0, 2.0, -2.0)
('Now do something with', 'user3', 3.0999999046325684, 2.0, -2.0)
('Now do something with', 'user4', 6.0, 3.200000047683716, -2.4000000953674316)

6. Add OSC processing to RFID program

I inserted the knect-snd.py program into Dump.py.

Dump_osc.py

#!/usr/bin/env python
# -*- coding: utf8 -*-

import RPi.GPIO as GPIO
import MFRC522
import signal

# OSC setting
from OSC import OSCClient, OSCMessage
client = OSCClient()
client.connect(("localhost", 7110))

continue_reading = True

# Capture SIGINT for cleanup when the script is aborted
def end_read(signal,frame):
    global continue_reading
    print "Ctrl+C captured, ending read."
    continue_reading = False
    GPIO.cleanup()

# Hook the SIGINT
signal.signal(signal.SIGINT, end_read)

# Create an object of the class MFRC522
MIFAREReader = MFRC522.MFRC522()

# This loop keeps checking for chips. If one is near it will get the UID and authenticate
while continue_reading:

    # Scan for cards    
    (status,TagType) = MIFAREReader.MFRC522_Request(MIFAREReader.PICC_REQIDL)

    # If a card is found
    if status == MIFAREReader.MI_OK:
        print "Card detected"

    # Get the UID of the card
    (status,uid) = MIFAREReader.MFRC522_Anticoll()

    # If we have the UID, continue
    if status == MIFAREReader.MI_OK:

        # Print UID
        print "Card read UID: "+str(uid[0])+","+str(uid[1])+","+str(uid[2])+","+str(uid[3])

        # Send OSC
        client.send( OSCMessage("/user/1", [uid[0], uid[1], uid[2], uid[3]] ) )

        # This is the default key for authentication
        key = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]

        # Select the scanned tag
        MIFAREReader.MFRC522_SelectTag(uid)

7. Create a program to receive OSC with openFrameworks

The sample program is also used here. Copy the sample program oscReceiveExample to openFrameworks / apps / myApps /.

cd openFrameworks/examples/addons
cp -r oscReceiveExample /home/pi/openFrameworks/apps/myApps/

Open ofApp.h.

cd /home/pi/openFrameworks/apps/myApps/oscReceiveExample/src
vim ofApp.h

Change `# define PORT 12345``` on the 7th line where the port number is set to `# define PORT 7110``` and save.

Go back up one folder and do make. When the compilation is finished, make run.

cd ..
make
make run

A blue window will open in the upper right corner of the screen. Launch another terminal and launch Dump_osc.py created in 6.

cd MFRC522-python
python Dump_osc.py

When you hold the NFC key chain attached to the NFC reader, the NFC UID is also displayed on the blue screen.

The video looks like this. (Click the image to go to YouTube)

Now that we've done this, it seems good to do the processing according to the UID received by oF.