pico-enc28j60

enc28j60 driver and lwIP integration for the Raspberry Pi Pico SDK (RP2040 microcontroller).

Requirements

• pico-sdk (Raspberry Pi Pico SDK)
• pico-extras with lwIP submodule

Remember to clone with submodules:

git clone --recurse-submodules https://github.com/raspberrypi/pico-extras.git

Or initialize submodules after a regular clone:

git clone https://github.com/raspberrypi/pico-extras.git
cd pico-extras
git submodule update --init --recursive

Usage

You can follow these instructions to build a lwIP app. The aim of this short tutorial is to successfully ping the device.

Clone this repository and the repositories mentioned in the Requirements section and note the clone paths.

Create a new empty directory that your project will reside in and cd to it.

mkdir picoping
cd picoping

Copy src/examples/lwip_integration.c and include/pico/enc28j60/examples/lwipopts.h and save it as main.c and lwipopts.h respectively in the new project root.

Remove the tcpecho_raw_init(); line before the main loop as well as #include "tcpecho_raw.h", because we only want a minimal example running. Edit the configuration section in the same file to reflect your setup, paying extra attention to the static IP address, netmask and gateway address as this example app won't include support for DHCP (pico-extras do not support it yet).

Copy external/pico_enc28j60_import.cmake, pico_extras_import.cmake and pico_sdk_import.cmake to your project's root and create a CMakeLists.txt with the following contents:

cmake_minimum_required(VERSION 3.19)

include(pico_sdk_import.cmake)
include(pico_extras_import.cmake)
include(pico_enc28j60_import.cmake)

project(picoping)

set(CMAKE_C_STANDARD 11)

pico_sdk_init()

include_directories(.)

add_executable(picoping main.c)
target_link_libraries(picoping pico_stdlib lwip pico_enc28j60)
pico_add_extra_outputs(picoping)

Now let's build it.

Create a build directory and configure the project passing paths to required components to CMake.

mkdir build

cd build

cmake \
    -DPICO_SDK_PATH=/path/to/pico-sdk/ \
    -DPICO_EXTRAS_PATH=/path/to/pico-extras/ \
    -DPICO_ENC28J60_PATH=/path/to/pico-enc28j60/ \
    ..

make

The compilation process should succeed and you should have a picoping.uf2 ready to load to your board.

After loading and rebooting you should be able to ping the IP address that you specified in the static configuration and get a response. If this is not the case, check the configuration and UART as a lot of debug information is printed there.

You can treat this app as a base for developing your own lwIP app. To make it easier, check out lwip-contrib as it contains examples such as tcp_echo_raw that are easy to integrate.