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For them that are confused 2bsd is best thought of as 16 bit bsd, and as such it's development carried on for far longer than would be thought.

I have to admit I am not sure why you need a 16 bit os for a 32 bit processer like the pic32. Best I can come up with is that because 16 bit is such a constrained memory space it runs well on small microcontrollers.

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The latter, but also 2.11bsd does not have virtual memory, and thus does not require an MMU. It was written with the segmentation features of a PDP-11 in mind, which so happen to adapt to PIC32 as it has kernel/user separation and memory protection via a kseg/useg segmentation (as opposed to a TLB with individual page protections).

It's not 16-bit as such. But since it's small enough to fit in 16-bit, it's small enough to fit on the small memory available on pic32.

It's like what if you have an 80386. It can run Linux (which is 32 bit). But your 80386 only has 1 megabyte of RAM. Then you can run Minix! Minix is available both in 32 bit and 16 bit versions. You could run the 16 bit, but then you get all the 16-bit limitations, so you can run the 32 bit version of Minix. Still small, but you get the added benefits of larger integers and larger address space.

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