This copy of Ethernet for Wiznet chips is intended only for Teensy boards. For using with any non-Teensy board, please use Arduino's Ethernet:
https://github.com/arduino-libraries/Ethernet
Or use the copy of Ethernet from your board's vendor, if they publish a modified copy of Ethernet specifically for their boards.
Back in 2018, I worked on unifying support for all 3 Wiznet chips (available at that time) with many performance improvements I had developed for Teensy's copy of Ethernet. I tested on many boards and it was released as Arduino Ethernet version 2.0.0.
https://www.pjrc.com/arduino-ethernet-library-2-0-0/
For a brief time, I was officially the maintainer for Arduino's Ethernet library. However, months later Arduino changed their repository access requirements, which I could not meet. I also became very busy with developing Teensy 4.0, leaving little time for testing Ethernet on other hardware.
In 2020, we released Teensy 4.1 with native ethernet, which offers vastly better performance than using a Wiznet chip. I do not anticipate spending much development time on Wiznet support in the foreseeable future. If you use Ethernet with Teensy, please consider Teensy 4.1 for future projects. The performance is so much better.
If you use a non-Teensy board, this is not the Ethernet library for you. Please do not report issue or ask for technical support for non-Teensy boards on this Teensy-specific repository.
Wiznet chips W5100, W5200 and W5500 are automatically detected.
Efficient block mode of W5200 & W5500 are used for data and multi-byte register access.
Wiznet socket registers are cached, which greatly reduces SPI communication overhead, at the cost of a small increase in RAM usage. TCP connections and UDP packets accessed in small chunks typically see a substantial performance boost.
Adafruit's Ethernet.init(CSPIN) extension is supported, to allow use of different pins for the chip select signal. Optimized direct register I/O is used for most Arduino compatible boards.
http://www.pjrc.com/teensy/td_libs_Ethernet.html
| Board | Chip | Shield / Module | Internet | Local (LAN) |
|---|---|---|---|---|
| Teensy 3.6 | W5500 | WIZ850io | 212.59 | 1143.58 |
| Teensy 3.6 | W5200 | WIZ820io | 202.44 | 1102.71 |
| Teensy 3.6 | W5100 | WIZ812MJ | 180.76 | 274.14 |
| ESP32 Feather | W5500 | Featherwing Ethernet | 211.06 | 965.76 |
| Teensy 3.2 | W5500 | WIZ850io | 205.37 | 958.06 |
| Teensy 3.2 | W5200 | WIZ820io | 215.44 | 914.78 |
| Teensy 3.2 | W5100 | WIZ812MJ | 170.07 | 234.55 |
| ChipKit Uno32 | W5500 | Seeed Ethernet W5500 | 177.19 | 858.81 |
| ChipKit Uno32 | W5200 | WIZ820io | 188.31 | 837.56 |
| ChipKit Uno32 | W5100 | Ethernet R2 (clone) | 159.72 | 272.18 |
| Arduino Due | W5500 | Seeed Ethernet | 214.44 | 689.69 |
| Arduino Due | W5200 | WIZ820io | 206.51 | 670.88 |
| Arduino Due | W5100 | Arduino Ethernet R3 | 105.98 | 109.73 |
| ESP8266 Feather | W5500 | Featherwing Ethernet | fail (dns) | 583.31 |
| Teensy LC | W5500 | WIZ850io | 200.51 | 479.73 |
| Teensy LC | W5200 | WIZ820io | 199.62 | 471.95 |
| Teensy LC | W5100 | WIZ812MJ | 126.40 | 137.77 |
| Arduino 101 (Intel) | W5500 | Seeed Ethernet W5500 | 168.96 | 359.32 |
| Arduino 101 (Intel) | W5200 | WIZ820io | 169.37 | 349.35 |
| Arduino 101 (Intel) | W5100 | Arduino Ethernet R3 | 42.39 | 43.60 |
| Teensy 2.0 | W5100 | WIZ812MJ | 81.07 | 84.85 |
| Arduino Uno R3 | W5500 | Seeed Ethernet W5500 | 185.44 | 329.00 |
| Arduino Uno R3 | W5500 | Arduino.org Ethernet2 | 195.32 | 329.60 |
| Arduino Uno R3 | W5200 | WIZ820io | 191.85 | 331.27 |
| Arduino Uno R3 | W5100 | Arduino Ethernet R3 | 79.11 | 82.66 |
| Arduino Uno R3 | W5100 | Ethernet R2 (clone) | 79.27 | 82.66 |
| Arduino Leonardo | W5500 | Seeed Ethernet W5500 | 179.98 | 328.14 |
| Arduino Leonardo | W5200 | WIZ820io | 183.69 | 330.30 |
| Arduino Leonardo | W5100 | Ethernet R2 (clone) | 78.75 | 82.28 |
| Mega 2560 (clone) | W5500 | Seeed Ethernet W5500 | 179.58 | 323.36 |
| Mega 2560 (clone) | W5200 | WIZ820io | 172.73 | 325.44 |
| Mega 2560 (clone) | W5100 | Ethernet R2 (clone) | 74.31 | 77.44 |
| Arduino Zero | W5500 | Seeed Ethernet W5500 | 183.13 | 305.26 |
| Arduino Zero | W5500 | Arduino.org Ethernet2 | 181.60 | 305.28 |
| Arduino Zero | W5200 | WIZ820io | 177.53 | 298.53 |
| Arduino Zero | W5100 | Arduino Ethernet R3 | 91.33 | 96.64 |
| Arduino Zero | W5100 | Ethernet R2 (clone) | 91.42 | 96.64 |
| Arduino MKR1000 | W5500 | MKR ETH | 181.27 | 298.93 |
| Arduino MKR1000 | W5200 | WIZ820io | 125.20 | 291.98 |
| Arduino Uno Wifi Rev2 | W5500 | Seeed Ethernet W5500 | 163.86 | 213.36 |
| Arduino Uno Wifi Rev2 | W5500 | Arduino.org Ethernet2 | 169.72 | 212.88 |
| Arduino Uno Wifi Rev2 | W5200 | WIZ820io | 161.94 | 212.19 |
| Arduino Uno Wifi Rev2 | W5100 | Arduino.org Ethernet2 | 69.50 | 72.23 |
| Arduino Uno Wifi Rev2 | W5100 | Ethernet R2 (clone) | 69.55 | 72.30 |
For more information about these benchmarks: https://www.pjrc.com/arduino-ethernet-library-2-0-0/
ESP32 may require edit to SPI.h to add SPI.transfer(data, size) espressif/arduino-esp32#1623