RT11 boot block 0 words ?

Pete Turnbull pete at dunnington.plus.com
Wed Jan 4 19:04:00 CST 2006

On Jan 4 2006, 21:49, Gooijen, Henk wrote:
> I would like to use the vast knowledge of this community, as a brief
> search through the calssiccmp archive gave no answer ...
> I can't get RT11 booted anymore on my 11/34.

> Is the first word (000240) the first word of block 0 of the RT11

Yes, AFAIR all standard DEC bootstraps have 240 as the first word of
the boot block.  240 is NOP.  Somebody once told me why they're done
that way, but I can't remember; only that it seemed sensible at the
time.  The only exceptions I know are the not-really-bootstraps on the
first block of non-bootable RSX disks, which contain a little bit of
code that prints something like "This is not a bootable disk" to the
console, and then halts.

It sounds a bit like your boot block has been wiped, and mostly
replaced with zeros.  Can you load the first block off the disk
manually, preferably not into location 000000, and examine it?  Should
be fairly easy with an RL11.  Then try some other block and make sure
that's not all zeros, to ensure it's the disk content you're seeing,
not some problem with the controller.

Pete						Peter Turnbull
						Network Manager
						University of York

More information about the cctech mailing list