I recently got one of these for cheap, and ended up finding a bunch of resources for both Windows and Linux, and thought I would share it here.
Most of it can actually be found at the NI ftp server, ftp.ni.com:
- /support/gpib/ni488224/Windows2000XP/ni488224.exe - NI 488.2 for Windows. I believe this is the last version that supports GPIB-ENET, should work with Win2k and XP, contains all the utilities to assign IP, update firmware, and scan and test communication with instruments.
- /support/gpib/linux/nienet-linux-1.2.tar.gz - Linux set of tools for assigning IP and updating firmware, as well as a C library that can be used to communicate with the controller.
- /support/gpib/firmware/GPIBENET/EnetA5.bin - Latest firmware
- /support/manuals/320910a.pdf - Software Reference Manual for the GPIB-ENET - It mentions an ESP-488 diskette which should also contain the C source code for all the communication functions, but I was not able to find this anywhere.
- /support/manuals/321243e.pdf - Getting started guide
The easiest way to work with it is using the Python implementation
here as mentioned by mimmus78.
You only really need libnienet.py which gives you the set of basic functions, although not all functions are implemented.
It is Python 2, but converting to 3 is not a big effort, it's mostly about changing internal functions to use bytes explicitly instead of strings.
If you do need some functions which are not implemented in libnienet.py, you can either use C, include ugpib.h and link to the library provided by e.g. the nienet-linux package above (32-bit only), or you can use ctypes to load the shared library into Python and have access to all the ib* C functions from there.
On 64-bit Python, you won't be able to load the 32-bit library directly, but you can use MSL-LoadLib package to achieve this.
I tried all 3 methods (pure Python, C, C->Python) and they all seem to work well.
Overall I'm quite happy with it, it's very convenient to be able to connect from any host and operation has been reliable so far, and if you can get it for cheap (I paid ~€30) then it's a no brainer.
Only downside is lack of support for more standard APIs like linux-gpib/PyVISA/sigrok, but on the other hand it's not rocket science to make use of the NI-488 functions to do what you need.