Re: Encapsulating Ada.Direct_IO

[Adam Beneschan <adam@irvine.com>]

On Nov 19, 12:24 am, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> On Thu, 18 Nov 2010 21:57:10 -0800, Dennis Lee Bieber wrote:
> > On Thu, 18 Nov 2010 18:05:49 +0100, "Dmitry A. Kazakov"
> > <mail...@dmitry-kazakov.de> declaimed the following in comp.lang.ada:
>
> >> On Thu, 18 Nov 2010 08:31:20 -0800 (PST), Adam Beneschan wrote:
>
> >>> Then there was a
> >>> DEC machine that used 36-bit words and represented strings by sticking
> >>> five 7-bit ASCII characters in each word, but I don't remember much
> >>> else.
>
> >> RADIX-50?
>
> >>http://en.wikipedia.org/wiki/DEC_Radix-50
>
> >    Why bother... 5 * 7bit => 35bits, easily fits into a 36bit word with
> > one left over!
>
> Because 3*7 = 21 >> 16. Under RSX-11, RT-11 they packed 3 file name
> characters into one 16-bit word. With 64K address space that was important.

Yeah, I remember the -11.  Cute little machines.  The 36-bit one I was
referring to was, I think, DEC-10; my recollection is that the
instruction set contained instructions that would let you stuff
characters of any size (including 7 bits) into words until it couldn't
fit any more and then go to the next word.

                                   -- Adam