Firing up the pdt11

[Chris Zach]

 > DEC controllers and DEC 8" drives cannot.  Not for any platform.
 >
 > Back in the day, DEC floppy users purchased pre-formatted floppies.
 > If you had an RX02, you could "INIT" an RX01 floppy to RX02 use -
 > essentially just rewriting the data portion of the sector to
 > double-density (256 bytes per sector) and I _think_ it's possible to
 > put it back.

Then I guess the question rattling around my brain is "How did I get 
this Elephant Memory systems disk formatted?" I know I didn't have an 
RX02 at the time, and I know DEC didn't do it for me as a favor. I know 
I bought a box of ten of them because I stuck the Elephant Memory 
Systems sticker on the front of my RM02 for good luck (I wonder where 
that drive is these days....) I thought that is why I kept the PDT11 
around.

I do have a card around here called an RXV21 from Plessy or something 
like that, maybe it could talk to an RX01 drive and format the disks?

Darn brain, there's a hole in it somewhere around this seemingly 
not-interesting fact. The disk though is still here, and is formatted 
RX01 with programs I wrote to it 30 years ago.

I did have an H11 computer, but it did not have the H27 disk drive, or 
at least I have no memory of owning one after looking at that one on Ebay.

In a practical sense, I really don't need to format anything anymore: 
The best use for the RX01 is to bootstrap BRUSYS so I can backup the 
EDSI disk with the TK50. Reading old disks is nice, but the first thing 
I do is create a .DSK image of them on a real disk. In theory it is 
handy to have a small capacity disk to do image transfers from SIMH 
using the PDP11GUI but now that I have Kermit up I can just transfer 
stuff that way....

Anyone want a pile of old RX02 formatted disks? I'll trade them for a 
few RX01 floppies just to have and to make PD: bootable disks for all 
the MiniMINCs out there.

> Back in the day, DEC floppy users purchased pre-formatted floppies.
> If you had an RX02, you could "INIT" an RX01 floppy to RX02 use -
> essentially just rewriting the data portion of the sector to
> double-density (256 bytes per sector) and I _think_ it's possible to
> put it back.

Hm. Well at least that makes disk alignments a lot simpler: If all the 
disks were originally formatted at DEC then interchange is pretty much 
guaranteed.

Ah DEC. Always wanted to get that last nickel from their user base.

CZ