Wiznet w550-evb-pico UDP server

[andrewmk]

I managed to get a UDP server working on a Wiznet w5500-evb-pico board. Loaded up CircuitPython 9.0.4 from https://downloads.circuitpython.org/bin/wiznet_w5500_evb_pico/en_GB/adafruit-circuitpython-wiznet_w5500_evb_pico-en_GB-9.0.4.uf2 and the matching Adafruit adafruit_wiznet5k and adafruit_ticks libraries.

import board
import busio
import digitalio
import time

from adafruit_wiznet5k.adafruit_wiznet5k import *
import adafruit_wiznet5k.adafruit_wiznet5k_socketpool as socketpool

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

##reset
W5x00_RSTn = board.GP20

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

cs = digitalio.DigitalInOut(SPI0_CSn)
spi_bus = busio.SPI(SPI0_SCK, MOSI=SPI0_TX, MISO=SPI0_RX)

# Reset W5x00 first
print("Initialising...")
ethernetRst.value = False
time.sleep(1)
ethernetRst.value = True

MY_MAC = "00:01:02:03:04:05"
PORT = 5000
TIMEOUT = None
MAXBUF = 1024

# Initialize ethernet interface with DHCP
eth = WIZNET5K(spi_bus, cs, is_dhcp=True, mac=MY_MAC, debug=False)
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))

pool = socketpool.SocketPool(eth)
sock = pool.socket(pool.AF_INET, pool.SOCK_DGRAM)
sock.bind((eth.pretty_ip(eth.ip_address), PORT))
buffer = bytearray(MAXBUF)

while True:
    eth.maintain_dhcp_lease()
    size, addr = sock.recvfrom_into(buffer)
    print(buffer[:size].decode())

[anecdata]

Thanks. I don't recall why I never got around to doing a WIZnet server, but I'll try to add an example for completeness. WIZnet socket examples should work like native wifi (once the custom setup is done).

[andrewmk]

I had great difficulty finding a working example of receiving UDP packets. Maybe it's because I wanted to use CircuitPython 9.04, or maybe it's that the Adafruit wiznet library seems to have changed recently, or both. Anyway in the end I picked apart the adafruit_ntp library and some other examples and got it working.