RX01 Bootstrap Loader

From: Jerome Fine <jhfine_at_idirect.com>
Date: Sat Feb 12 18:53:27 2000

>CLASSICCMP_at_trailing-edge.com wrote:

> >Due to the instruction set incompatibilities between the 11/20 and other
> >11s, will they even run RT11 V30B with 8K core?
> RT11 V03B ought to be OK, as long as you have enough memory. I know that
> 12K words core is enough (I have V03B on an 11/04 with 12K core), I suspect
> it will fit in 10 or 8K.

Jerome Fine replies:

I see that V3.0 distribution of RT-11 has a MAC8K.SAV file. Does this
mean that the total memory, including the RT-11 Operating System, can
run in 8 KBytes with MAC8K running in somewhat less? OR, does
MAC8K.SAV require 8 KBytes just to run itself (000000 to 017776)
with RT-11 being located above 020000 (octal)?

Is it possible that you have a complete V03.0B distribution? I have several
incomplete sets and also a V3.0 distribution from 14-Aug-1977 with the boot
floppy (RX01) partly overwritten (about the first 287 blocks) which means that
seven SAV files are not available, but can fortunately be replaced by later
versions that are available from V3.0B files which should be compatible if someone
wants for some reason to use the actual V3.0 Operating System of RT-11 as
opposed to V3.0B of RT-11. I believe that V3.0B files have a date of
11-Mar-1978.

Also, I looked at the SYSMAC.SML file and note that there is no .DrVTB
macro present (also no .DrSet macro although the information is hard coded
into the various device drivers, and obviously the SET commands do work).
Does this mean, in your opinion (maybe you or someone else remembers
that far back - 22 years ago) that an LS.MAC device driver can't operate
in V3.0B since RT-11 is not yet smart enough to use dual CSR/VECTOR
hardware that requires two .DrAst entries? I notice that V4.0 of RT-11
finally has the LS.SYS device driver, but there is none present in V3.0B
of RT-11, only the LP.SYS device driver.

Sincerely yours,

Jerome Fine
Received on Sat Feb 12 2000 - 18:53:27 GMT