cardreader.py

from time import sleep, time
import sys
from mfrc522 import SimpleMFRC522
import RPi.GPIO as GPIO

readers = []
poll_list = list()
curr_poll_list = list()
RESET_PIN = 21  # In BCM pin number. See: https://pinout.xyz


def read_init():
    rfid_count = 18
    for i in range(0, rfid_count):
        poll_list.append(i)
    curr_poll_list = poll_list.copy()

    GPIO.setmode(GPIO.BCM)

    for i in range(0, rfid_count):
        # Parameters are bus and device number respectively. Device number is allias to
        # Chip Select (Slave Select) in SPI Protocol.
        # /dev/spidev<bus>.<device>
        # Pin association to the device numbers configured by device tree object.
        # See: /home/alarm/spi-cs-extend.dts
        # See: https://gist.github.com/mcbridejc/d060602e892f6879e7bc8b93aa3f85be
        readers.append(SimpleMFRC522(0, i, 800000))

    # Its recommended to reset MFRC522 after each polling. Pulling Reset_Pin to low
    # (by setting the ping to low mode in out settings) turns off the sensors until
    # the pin is high again.
    GPIO.setup(RESET_PIN, GPIO.OUT)

    GPIO.output(RESET_PIN, GPIO.LOW)
    sleep(0.01)

    GPIO.output(RESET_PIN, GPIO.HIGH)
    sleep(0.01)


def read_process():
    reads = dict()
    poll_duration_in_s = 2.5
    try:
        # One-shot reads might miss. So its better to poll multiple times.
        old_time = 0
        total_read = 0
        while True:
            if time() - old_time < poll_duration_in_s:
                for i, v in enumerate(curr_poll_list):
                    readers[v].READER.MFRC522_Init();
                    # print(v)
                    id, text = readers[v].read_no_block()
                    if id:
                        reads[v + 1] = id
                        txt = "0x001"
                        #readers[v].write(txt) # RFID TAg eklemek istersek bu komutu çalýþtýracaðýz.
                        curr_poll_list.remove(v)
                    print("%d ID: %s %s" % (i, id, text)) 
		    
                    #print(list(str(text).encode('ascii')))
                total_read += 1
                # print(curr_poll_list)

            else:
                if total_read != 0:
                    return reads
                for number, id in sorted(reads.items()):
                    print("RFID NUMBER: %d KEY ID: %d" % (number, id))

                reads.clear()
                print("Total Read = %d.\tReading the devices..." % (total_read))
                total_read = 0
                old_time = time()
                curr_poll_list = poll_list.copy()
                GPIO.output(RESET_PIN, GPIO.LOW)
                sleep(0.05)

                GPIO.output(RESET_PIN, GPIO.HIGH)
                sleep(0.05)


    except KeyboardInterrupt:
        GPIO.cleanup()
        raise


def to_ascii(text):
    ascii_values = [ord(character) for character in text]
    return ascii_values