>> don`t want to run fancy tools on it or X. The only thing that is important 
>> to me is the SDCC compiler (sdcc.sourceforge.net) I hope it will work with 
>> this little RAM.
>
> 170 MB should be enough space for a stripped down NetBSD. I don't know about 
> sdcc though.
>
> Also 4MB of memory is too little. You will need to build a custom kernel that 
> is small enough. Maybe it is not possible.

if we are talking about "will NetBSD boot on 4MB?" the answer is yes, 
including latest -current (tested :).

if we are talking about "will NetBSD be usable on 4MB?" NetBSD-1.4 series 
is probably the last usable.

>> Of course the notebook has no NIC or CDROM. I have to make floppy sets or 
>> an installation over Nullmodemcable. I think floppy will be the way to go.
>
> Floppies are too slow and too unreliable. You could spend a week if you 
> attempted 100 floppies. Use floppies to boot installer and use slip over your 
> null modem -- that is how I installed mine for a few years until one day the 
> pcmcia started working :)

not true. i installed NetBSD-1.5 through floppies with 2 hours on my 
notebook with 200MB disk whis way.

1) manually made fs and swap partition, newfs'ed the fs partition and 
mounted it at /mnt


2) on other machine i tarred up all required files from binary sets this 
way

tar cvf - sets|split -b1440k

getting lots of files like xaa,xab,xac etc...


3) for each file i did

cat file >/dev/fd0b

and in the same time on my notebook

cat /dev/fd0b >file

in case of failed floppy i just used other for same file.

no need to have floppies for everything! 2-3 floppies are enough (+boot 
floppy of course)

4) when all files transferred:

cat x??|tar xvf -

rm x??

now in subdirectory "sets" all system is ready to be installed from. i did 
manually but sysinst should work too.