---
title: "W55RP20 MicroPython Examples for tcp client"
url: "https://maker.wiznet.io/josephsr/projects/w55rp20-micropython-examples-for-tcp-client/"
markdown_url: "https://maker.wiznet.io/josephsr/projects/w55rp20-micropython-examples-for-tcp-client/md"
type: "WCC: WIZnet Created Content"
author: "Joseph"
editor: "WIZnet"
editor_url: "https://maker.wiznet.io/"
original_author: "Joseph"
license: "MIT license (MIT)"
published: "2025-02-07"
language: "en"
hardware: ["WIZnet W55RP20-EVB-Pico"]
likes: 0
views: 2104
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# W55RP20 MicroPython Examples for tcp client

> This MicroPython project establishes a TCP client using a WIZnet W5x00 Ethernet module, continuously connecting to a server and echoing received data.

Original author: Joseph

## Components

- **WIZnet W55RP20-EVB-Pico** x 1 ([docs](https://wiznet.io/products/powered-by-raspberry-pi/w55rp20-evb-pico))
- Software: **MicroPython** ([docs](http://micropython.org/))

## Documents and links

- [micropython examples for tcp_client](https://github.com/WIZnet-ioNIC/WIZnet-ioNIC-micropython-examples/blob/main/tcp_client.py) (code)

## Article

### **Source Code ExplanationImports:**

- `socket`, `usocket`: Used for TCP communication.

- `machine`, `network`: Handles hardware and networking functionalities.

- `time`, `uasyncio`: Provides timing and async support.

- `w5x00_init`: Initializes the WIZnet W5x00 Ethernet module.

**Connection Settings:**

- `destip = '192.168.7.3'` and `destport = 2300` define the target server.

- `conn_info = (destip, destport)` holds the connection tuple.

- `conn_flag`: Tracks connection status.

`**client_loop(ip)**`**:**

- Establishes a persistent TCP connection to the server.

- Continuously attempts reconnection if the connection fails.

- Receives data (`s.recv(2048)`), decodes it, prints it, and echoes it back.

`**main()**`**:**

- Calls `w5x00_init()` to configure the W5x00 Ethernet module.

- Extracts IP and starts `client_loop(ip)`.

**Execution Flow:**

- Runs as `__main__`, initializes Ethernet, and starts the TCP client.

---

### ▶ **How to RunPrepare Hardware:**

- Connect the WIZnet W5x00 Ethernet module to the MicroPython board.

- Ensure the board is networked via Ethernet.

**Deploy Code:**

- Upload the script to the MicroPython board.

- Run `main.py` via REPL or automatically on boot.

**Set Up a TCP Server (for testing):**

```plaintext
nc -lvp 2300
```

Or use a Python TCP server:

```python
import socket
s = socket.socket()
s.bind(('0.0.0.0', 2300))
s.listen(1)
conn, addr = s.accept()
while True:
   data = conn.recv(2048)
   if data:
       conn.send(data)
```

### **Execution Result**

- **If connection succeeds:**

```plaintext
my ip is 192.168.7.100
Loopback client Connect! (0.5) seconds
recv from 192.168.7.3:[2300]: Hello Server
```

- **If the server disconnects:**

```plaintext
disconnect [Errno 104] ECONNRESET
connect error [Errno 111] ECONNREFUSED
```

- **Data Echoing:**
  - Any received message is echoed back to the sender.

---

Source: https://maker.wiznet.io/josephsr/projects/w55rp20-micropython-examples-for-tcp-client/