Micropython-ESP32-W5500 (Wiznet)

Enhanced and SSL support version (untested): Check ESP32-Wiznet-W5500-SSL-Micropython.

Connect your ESP32 to the W5500 (Wiznet) Ethernet module and use Python's requests as an HTTP client.

Hardware

• ESP32 ESP-WROOM-32
• W5500 (or W5100)

Firmware

• Micropython

Tools

• Python
• ampy (Install using pip)

  pip install adafruit-ampy

Wiring

ESP32	W5500
3V3	V
GND	G
GPIO5 (VSPI_CS)	CS
GPIO18 (VSPI_CLK)	SCK
GPIO23 (VSPI_MOSI)	MO
GPIO19 (VSPI_MISO)	MI
GPIO34	RST

Instructions

1. Upload Required Files

Upload the following files to your ESP32 using ampy:

• wiznet5k.mpy
• wiznet5k_dhcp.mpy
• wiznet5k_dns.mpy
• wiznet5k_socket.mpy
• sma_esp32_w5500_requests.mpy

Example (replace COM9 with your ESP32’s serial port):

ampy --port COM9 put wiznet5k.mpy
ampy --port COM9 put wiznet5k_dhcp.mpy
ampy --port COM9 put wiznet5k_dns.mpy
ampy --port COM9 put wiznet5k_socket.mpy
ampy --port COM9 put sma_esp32_w5500_requests.mpy

2. Run the Code

Upload the following code to your ESP32 to fetch data over HTTP using the W5500 module.

from wiznet5k import WIZNET5K
from machine import Pin, SPI
import wiznet5k_socket as socket
import time
import struct
import sma_esp32_w5500_requests as requests

# Initialize SPI and W5500
spi = SPI(2)
cs = Pin(5, Pin.OUT)
rst = Pin(34)
nic = WIZNET5K(spi, cs, rst)

# Define the URL to fetch data from
TEXT_URL = "http://quietlushbrightverse.neverssl.com/online/"

# Display chip info and network status
print("Chip Version:", nic.chip)
print("MAC Address:", [hex(i) for i in nic.mac_address])
print("My IP address is:", nic.pretty_ip(nic.ip_address))
print("IP lookup google.com: %s" % nic.pretty_ip(nic.get_host_by_name("google.com")))

# Initialize requests object with socket and Ethernet interface
requests.set_socket(socket, nic)

# Fetch and print content from the URL
print("Fetching text from", TEXT_URL)
r = requests.get(TEXT_URL)
print('-' * 40)
print(r.text)
print('-' * 40)
r.close()

print("Done!")

Limitations

• Works only with HTTP (not HTTPS). For SSL support, check out the enhanced version here.

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How to Log in to ASP.NET Forms (Forms-Based Authentication)

If you need to log in to an ASP.NET form and retrieve a cookie for subsequent private page requests, follow these steps. The login page is logon.aspx, and the private page is default.aspx.

1. Get the Login Page

Fetch the login page and extract the necessary form values.

2. Post Username, Password, and ViewState

Send a POST request with the username, password, and __VIEWSTATE from the page.

3. Send the Cookie for Private Pages

Once logged in, capture the cookie and use it to access private pages.

Here is the code to log in and get the cookie:

from wiznet5k import WIZNET5K
from machine import Pin, SPI
import wiznet5k_socket as socket
import sma_esp32_w5500_requests as requests

def findVal(txt, tag):
    g = txt[txt.find(tag):]
    g = g[g.find("value"):]
    g = g[:g.find("/>")]
    g = g.strip()
    g = g.replace('value="', "")
    g = g[:-1]  # remove the trailing quote
    return g

# Initialize SPI and W5500
spi = SPI(2)
cs = Pin(5, Pin.OUT)
rst = Pin(34)
nic = WIZNET5K(spi, cs, rst)

# Display chip info and network status
print("Chip Version:", nic.chip)
print("MAC Address:", [hex(i) for i in nic.mac_address])
print("My IP address is:", nic.pretty_ip(nic.ip_address))

# Initialize requests object with socket and Ethernet interface
requests.set_socket(socket, nic)

# Log in to the website
url = 'http://win.smait.ir/logon.aspx'
g = requests.get(url).text

# Extract the __VIEWSTATE and other hidden form values
payload = {
    '__EVENTTARGET': "",
    '__EVENTARGUMENT': "",
    '__VIEWSTATE': findVal(g, '__VIEWSTATE'),
    '__VIEWSTATEGENERATOR': findVal(g, '__VIEWSTATEGENERATOR'),
    '__EVENTVALIDATION': findVal(g, '__EVENTVALIDATION'),
    'txtUserName': "1",
    'txtUserPass': "2",
    'Button1': "Login"
}
print(payload)

# Send POST request to log in
p = requests.post(url, data=payload)
print(p.headers)

# Get the cookie from the response headers
cookie = p.headers['set-cookie'].split('; expires=')[0]
print(cookie)

# Use the cookie to access the private page
p2 = requests.get('http://win.smait.ir/default.aspx', headers={"Cookie": cookie})
print(p2.text)

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License

This project is licensed under the MIT License - see the LICENSE file for details.