W5500-EVB-Pico board 
adafruit-circuitpython-wiznet_w5500_evb_pico-en_GB-8.0.0-beta.6.uf2
adafruit-circuitpython-bundle-8.x-mpy-20230126

import board
import busio
from adafruit_wiznet5k.adafruit_wiznet5k import WIZNET5K
import adafruit_wiznet5k.adafruit_wiznet5k_socket as socket
import adafruit_minimqtt.adafruit_minimqtt as MQTT
import digitalio
import time

##SPI0
SPI0_SCK = board.GP18
SPI0_TX = board.GP19
SPI0_RX = board.GP16
SPI0_CSn = board.GP17

##reset
W5x00_RSTn = board.GP20

def on_connect(client, userdata, flags, rc):
    print("MQTT connected to broker")

def main():

    # Setup your network configuration below
    # random MAC, later should change this value on your vendor ID
    MY_MAC = (0x00, 0x01, 0x02, 0x03, 0x04, 0x05)
    # Setup your network configuration below
    IP_ADDRESS = (192, 168, 1, 250)
    SUBNET_MASK = (255, 255, 255, 0)
    GATEWAY_ADDRESS = (192, 168, 1, 1)
    DNS_SERVER = (192, 168, 1, 1)

    ethernetRst = digitalio.DigitalInOut(W5x00_RSTn)
    ethernetRst.direction = digitalio.Direction.OUTPUT

    # For Adafruit Ethernet FeatherWing
    cs = digitalio.DigitalInOut(SPI0_CSn)
    # For Particle Ethernet FeatherWing
    # cs = digitalio.DigitalInOut(board.D5)
    spi_bus = busio.SPI(SPI0_SCK, MOSI=SPI0_TX, MISO=SPI0_RX)

    # Reset W5500 first
    ethernetRst.value = False
    time.sleep(1)
    ethernetRst.value = True

    # Initialize ethernet interface with DHCP
    # eth = WIZNET5K(spi_bus, cs)
    # Initialize ethernet interface without DHCP
    # *****  For DHCP to work correctly. Stop the code properly - STOP button, then click on play
    # otherwise WIZNET5K function call hangs and no IP address is recovered
    eth = WIZNET5K(spi_bus, cs, is_dhcp=False)
    eth.ifconfig = (IP_ADDRESS, SUBNET_MASK, GATEWAY_ADDRESS, DNS_SERVER)

    print("Chip Version:", eth.chip)
    print("MAC Address:", [hex(i) for i in eth.mac_address])
    print("My IP address is:", eth.pretty_ip(eth.ip_address))

    socket.set_interface(eth)

    MQTT.set_socket(socket, eth)
    
    g_mqtt_client = MQTT.MQTT(
        broker="broker ip",
        port=1883,
        username="user",
        password="password"
    )

    g_mqtt_client.on_connect = on_connect
    print("connecting")
    
    g_mqtt_client.connect()
    
    g_mqtt_client.subscribe("HELLO/WORLD")
    
    print("connected")
    while True:
        g_mqtt_client.publish("DETECTOR/ZONE1/ALIVE", "alive")
        print("loop")
        g_mqtt_client.loop()

if __name__ == "__main__":
    main()