It turns out to be linux
. Latest firmware seems to be a 3.4 kernel. The system part is pretty lightweight and based around busybox. There's a bunch of GPL stuff in there and the e-series manual says that the licence can be found at "www;raymarine.com" but sticking "GPL" into the search engine
on their web site yields nothing and nothing for "GNU". Anyone know where Raymarine
keep their copy of the GPL and the source code covered by it?