nfcente/main.py

from micropython import const
from os import uname
from machine import SoftSPI, Pin

import uasyncio as asyncio

import aioble
import bluetooth
import random
import struct
import machine
import time
import gc
import sys

import pn532_i2c

# Based on example from: https://github.com/micropython/micropython-lib/blob/master/micropython/bluetooth/aioble/examples/temp_sensor.py
# Unfortunately, there is no license information for aioble anywhere to be found...

# Also based on https://github.com/somervda/nfc-tester which doesn't come with a license file either...

RFID_BASE = lambda x: "1408%s-1337-BABE-B00B-C0FFEEC0FFEE" % (((4 - len(str(x))) * "0") + str(x))
RFID_SERVICE_UUID = bluetooth.UUID(RFID_BASE(1))
RFID_CHAR_UUID = bluetooth.UUID(RFID_BASE(2))

_ADV_INTERVAL_MS = 250_000

rfid_service = aioble.Service(RFID_SERVICE_UUID)
rfid_characteristic = aioble.Characteristic(
    rfid_service, RFID_CHAR_UUID, read=True, notify=True
)
aioble.register_services(rfid_service)

async def peripheral_task():
    while True:
        try:
            async with await aioble.advertise(
                _ADV_INTERVAL_MS,
                name="RFIDTest",
                services=[RFID_SERVICE_UUID],
            ) as connection:
                print("Connection from", connection.device)
                await connection.disconnected()
        except BaseException as e:
            print("Exception in peripheral_task:", e)

async def read_task(rdr, buzzer=None):
    # Start listening for a card
    print("Waiting for RFID/NFC card...")

    while True:
        try:
            do_read(rdr, buzzer)
        except Exception as e:
            print("Exception in read_task:", e)
        await asyncio.sleep_ms(100)

def do_read(rdr, buzzer=None):
    gc.collect()
    last_uid = None
    while True:
        try:
            uid = rdr.read_passive_target(timeout=0.2)
            if last_uid == uid:
                continue
            if uid is None:
                print("No card found")
                last_uid = None
                continue

            struid = "".join(['{:0>{w}}'.format(hex(i)[2:], w=2) for i in uid])
            print("Found card with UID:", struid)
            rfid_characteristic.write(uid)

            if buzzer:
                buzzer.value(1)
                time.sleep_ms(300)
                buzzer.value(0)

            last_uid = uid

        except Exception as e:
            print("Something failed:", e)
            pass

        finally:
            time.sleep_ms(100)

async def main():
    try:
        i2c = machine.I2C(0, scl=machine.Pin(1), sda=machine.Pin(0))
        devices = i2c.scan()
        if len(devices) == 0:
            print("No i2c device !")
            return 1

        else:
            print('i2c devices found:', len(devices))
            for device in devices:
                print("Decimal address: ", device, " | Hex address: ", hex(device))

        pn532 = pn532_i2c.PN532_I2C(i2c, debug=False)
        ic, ver, rev, support = pn532.get_firmware_version()
        print("Found PN532 with firmware version: {0}.{1}".format(ver, rev))
        pn532.SAM_configuration()

        time.sleep_ms(100)

        gc.collect()

        buzzer = Pin(27, Pin.OUT)
        buzzer.value(0)

        await asyncio.gather(
            peripheral_task(),
            read_task(pn532, buzzer)
        )

    except KeyboardInterrupt:
        print("Interrupted")

    except Exception as e:
        print("Exception in main:", e)
        return 1


asyncio.run(main())