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J. David Bryan wrote:
<blockquote cite="mid200602122254.k1CMsgaj019115@mail.bcpl.net"
type="cite">
<pre wrap="">
For some reason, delivery of your message was delayed until the 10th. Are
you still having trouble?
</pre>
</blockquote>
Probably somthing to do with a new list member making a first
submission. Not realy important - gave me some time to persue some
other problems.<br>
<blockquote cite="mid200602122254.k1CMsgaj019115@mail.bcpl.net"
type="cite">
<blockquote type="cite">
<pre wrap="">The Interdata SIMH documentation says that a non-attached disk appears
as "not ready". My command file looks like:
set cpu 832
set dm0 msm300
att -e dm0 dm0.dsk
att mt0 boot.tap
d 78 85a18540
set cpu hist=100
set br 954a
boot mt0
</pre>
</blockquote>
<pre wrap=""><!---->
I don't know anything about the Interdata machines, but your command file
looks reasonable to me.
I note without understanding this comment in the Interdata simulator
documentation:
"To boot OS16/32, the hex form of the operating system file's
extension must be placed in locations 7E:7F."
I gather that you're accommodating that requirement?
</pre>
</blockquote>
I'm booting from tape, so some other considerations apply. The "d 78
85a18540" is required for booting the OS from tape. SIMH will boot
diagnostics from tape without this extra initialization. The OS boot
from tape does some strange things. The Auto Load instruction reads the
first 80 bytes of an about 1.5k boot loader from the tape. Naturaly all
sorts of data overruns occur in the data path from the tape drive as
the tape keeps spinning. Those first 80 bytes of the tape get the drive
reset and read the whole block this time somewhere higher in memory.
This bootloader can load an os off of tape or disk, thus in addition to
the locations that need to be initialized for the autoload instruction
(and are initialized by the SIMH boot command), locations need to be
initialized to tell the boot loader where to find the OS. In this case
on the same tape as the bootloader. I get the OS to load and start just
fine. It is a credit to SIMH that it handles this tape drive abuse just
fine.<br>
<blockquote cite="mid200602122254.k1CMsgaj019115@mail.bcpl.net"
type="cite">
<pre wrap="">
Although I know nothing about your machines or the fidelity of the SIMH
simulation, from extensive work with the HP 2100 simulators, I can
recommend that a good place to start would be with the original Interdata
system diagnostics, if they are available to you. Running the HP
diagnostics against the simulator resulted in 83 bugs being reported and
fixed. SIMH now runs the HP RTE series of multiuser, multiprogramming
operating systems flawlessly, whereas they wouldn't boot when I started.
Tracking down problems one at a time via the diagnostics proved far easier
than trying to determine why an interrupt-driven RTOS wouldn't run.
</pre>
</blockquote>
There are two Interdata disk controlers supported by SIMH, I've got one
working in both OSs, the other fails in both OSs.<br>
<br>
Running diagnostics is next, before I make too much noise on the list.<br>
<br>
I will, however give a quick synopsis here:<br>
<br>
Single stepping the OS driver I discover that basicly what is happening
is that the driver does a "Sense Status" instruction to the device and
gets back a "Device Not Ready" status and gives up. The Interdata SIMH
documentation says that "Device Not Ready" is returned if a file is not
attached. Stepping through the SIMH code that implements the SS
instruction looks like that is indeed what is happening - the SS
instruction thinks there is no device attached. Given that the
Interdata IDE disk controler is reputed to pass diagnostics (which I
should be able to try in the next day or two) it is reasonable for me
to suspect that my having somthing set up wrong is at least as likly as
a bug in the code.<br>
<br>
Actual details later.<br>
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