[comp.periphs] LIBS hard drive questions

bgr@wild.Rice.EDU (Robert G. Rhode) (08/15/89)

I have recently acquired a LIBS100 CLSI 80MB hard drive with 7 disk packs.
It came with no documentation or promises (the price was right: free), 
and I want to try to interface it to my Atari ST through the DMA port.

I have been told:

1) the hard drive came from a PDP-11 computer and has not been used for two
years.  There was a second which was said to work, which was given to some-
one else.  This one is suspected (by its former operator) to need a fuse.

2) the PDP-11 is a Uni-bus machine.  Did I get that right?

3) the hard drive currently has no controller.

What I thought I might do is try to make this thing bark like a SCSI device,
then buy a SCSI controller and driver software, saving myself all of the hassle
except the translation from Uni-bus to SCSI. (A trivial job, right? :-) )

What I need to know is:

What is the operating language of the LIBS100 CLSI drive (i.e. how many bits
wide are the words, what are the pinouts, what are the control codes, etc.),
or alternately where can I find docs, who makes controllers for it, and is it
even worthwhile to consider trying to make it look like a SCSI device, or
should I just hack straight from Uni-bus to DMA?  Will I need to multiplex
16-bit drive words into 8-bit Atari words?  32-bit?  Can a contoller be made
using fairly straightforward TTL?  How complex is driver software?

I haven't a clue where to begin, so if anyone can help me out I'd really
appreciate it.  What I need most now are specifications, I guess.


Robert Rhode			|	"Today's champion
rhode@ricevm1.rice.edu		|    is tomorrow's crocodile shit."
bgr@uncle-bens.rice.edu		| Monty Python : Contractual Obligation Album