10 Oct
2003
10 Oct
'03
7:41 p.m.
Ron Hudson wrote:
Jay West wrote:
What OS was I running?
My initial guess was DOS, but I'd suspect HP's standalone RJE station with
processing happening on a mainframe somewhere else. I actually seem to have
a pretty extensive library of paper tapes and manuals for the standalone RJE
system.
The boot loader was stored at (i think) 102077 (punch
this in the
switch register and hit run???)
102077 is generally used as the T register display upon a "good halt", not a
starting address. So when you ran the boot loader, if it loaded correctly,
you would get a 102077.
Right. That's the halt code -- actually, the 2100 displays the last
instruction, which in this
case is the halt instruction (1020xx)...
Depending on how much core memory was in the machine, the boot loader
started at x7700 octal, where
x was set depending on the core size. For a 32K machine, x was 7 giving
a starting program counter
of 77700 for the paper tape reader boot and 77740 for the disk boot...
(but you knew this part, Jay :-)
Jay West