RetroBSD is a port of 2.11BSD Unix intended for embedded systems with fixed memory mapping. The current target is Microchip PIC32 microcontroller with 128 kbytes of RAM and 512 kbytes of Flash. PIC32 processor has MIPS M4K architecture, executable data memory and flexible RAM partitioning between user and kernel modes. The project is open source and hosted at RetroBSD.org
PIC32-Pinguino was used by RetroBSD developers since long time as it’s small and easy to use, but the Pinguino bords processor PIC32MX440 has not enough RAM to hold the RetroBSD, so we got number of requests to release PIC32-PINGUINO-MICRO with PIC32MX795F512H processor which is pin to pin compatible, so we run small batch of these boards and named them PIC32-RetroBSD, these surely can be used with Pinguino and MPIDE, but note that you must have additional PIC-KIT3 to re-flash the proper bootloader, as RetroBSD bootloader is different and we ship these boards with RetroBSD bootlaoder. Also you will need PIC32-RetroBSD-SD for the file system.
We are shipping today free PIC32-RetroBSD boards to the 9 RetroBSD developers.
olimex 
Dec 16, 2015 @ 22:44:54
Can the PIC32-RetroBSD-SD Image downloaded anywhere (like on http://retrobsd.org/wiki/autobuild.php ) ?
Dec 17, 2015 @ 09:36:50
It should be “retrobsd-pinguino-micro-2015-12-03.zip” – it is always the best idea to refer to the RETROBSD web-site for the latest firmware and images.
Dec 17, 2015 @ 15:29:25
Please document on the web shop page that this comes with RetroBSD bootloader because it now states exactly the opposite “If you do not want to use Pinguino IDE and you want to program this board with a PIC-ICD2-POCKET or PIC-KIT3 …”
Dec 17, 2015 @ 15:31:42
thanks!the usual copy+paste mistakes 🙂
Dec 25, 2015 @ 11:07:07
Here is a video about this board and RetroBSD project, from BSD Now videocast: https://www.youtube.com/watch?v=TSz4yn63YNw