[Simh] RSTS/E 10.1-L and Paper tape

[Johnny Billquist]

On 2016-01-07 01:00, Mark Pizzolato wrote:
> On  Wednesday, January 6, 2016 at 2:49 PM, Johnny Billquist wrote:
>>>> Other options could be using a disk with the files on it, setting up
>>>> tapes, but also, if simh supports it, possibly using the virtual DOS
>>>> device, that other emulators have, as well as using DECnet.
>>>>
>>> Does the virtual DOS device work in linux/mac?
>>
>> Does the DOS device exist in simh would be the first question...
>
> No such thing is in simh.
>
> It is not clear exactly what or how this would work with the legacy
> systems that are around.

Not sure how that matters...

> It would be hard to imagine that actually emulating a DOS disk structure
> (FAT, NTFS or other) would be useful since then someone would have
> to write driver software for each legacy OS to interpret this completely
> foreign structure.  The next logical step would be to implement some
> 'natural' file system that some least common denominator of legacy
> Systems could understand.  This might be RT-11 format maybe.

Uh? You are thinking too much.
The device actually have functions to find a specific file, open the 
specific file, read and write byte ranges, and close the file. How the 
host file system looks like, or other semantics, are totally hidden from 
the user of the device. You essentially ask it OPEN("FOO.BAR") and it 
either succeeds or fails. After that, you can read N bytes, write N 
bytes, seek to a specific position, or close the file.
So you just have a DMA address, a byte count, and a command register. 
Not much more. I can dig up my notes on exactly how it works if anyone 
is interested. It was years since I wrote my device driver.

But I don't have time to actually implement this in simh myself at the 
moment.

> If someone wants to take on this concept, I'll be open to looking at what
> they're thinking.
>
> Meanwhile, the 'crude' way to exchange data on most simulators can
> actually be done with cut and paste in console or telnet sessions.

Indeed. That also works. But it is really problematic when copying data 
into the simulator, since this goes through the OS terminal driver, 
which have limitations. Pasting in data often leads to data loss in my 
experience. But copying out works fine.

> Real files can move over the network (possibly with a couple of hops)
> from modern systems via tcp (FTP) into VMS or RSX (thanks Johnny)
> systems which can then pass them via DECnet to RSTS.

Yes. DECnet is a viable option.

But I still maintain that KERMIT is really the easiest solution to start 
with.

	Johnny

-- 
Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol