This repository contains a generic ENC28J60 driver with hardware abstraction and an lwIP network interface port. An example implementation for the hardware abstraction is provided for the EnergyMicro Gecko microcontroller, on which the example of an lwIP project using the driver can be run.

It provides all the functionality required for stable send/receive operation (was tested against concurrent flood pings and TCP requests), but has room for extension, especially with respect to error reporting and optimization. (Current code relies on polling only, and utilizes neither DMA nor interrupts.)

• Get a ENC28J60 chip with UEXT connector (MOD-ENC28J60 from Olimex)

• Get a Gecko chip with UEXT connector (EM-32G880F128-H from Olimex)

• Get an SWD programmer (any of the EnergyMicro starter kits)

• Wire everything up the only way the connectors fit

• Get an arm-none-eabi-gcc (eg. from the Debian package gcc-arm-none-eabi)

• Get the EFM32 toolchain set up (FIXME: that could need some more details)

• Fetch the lwIP library and build the example code

  cd examples/netblink/
  git clone git://git.savannah.nongnu.org/lwip.git -b DEVEL-1_4_1
  make
  

• Upload the program:

  make upload
  

• Configure your Ethernet interface as 192.168.0.1/24

• Test everything:

  socat udp:192.168.0.2:1234  -
  

• Enjoy that the LED blinks every time you send a line.

The driver itself resides in ./enc28j60driver/. It is basically stack agnostic, ie. it just implements typical operations conducted with the ENC28J60 (eg. setup, doing a self test, reading a received frame into pre-allocated memory).

If compiled with -DENC28J60_USE_PBUF, two small additional functions, @ref enc_read_received_pbuf and @ref enc_transmit_pbuf, are added, which are designed to use the lwIP pbuf memory management system. This is to keep the interfaces simple.

The lwIP netif implementation for the driver resides in lwip/netif, following the naming structure of the lwIP project (at least I hope so).

It is suitable for lwIP version 1.4.1 and the current (as of 2013-01-22) 1.5 development version.

Due to the interfaces provided by the driver itself, it is rather minimal, and only consists of a init and a polling routine (which, as the name implies, is to be called as often as possible).

An implementation of the hardware backend for the EFM32 Gecko platform can be found in efm32/enchw. It utilizes the free (zlib-style licensed) emlib library provided by EnergyMicro, and manages transmission of bytes over the chips' SPI peripherials. The very pinouts are defined in the enchw-config.h files, which are provided for particular development boards in efm32/boards/, along with very simple board drivers that are used in the examples.