[Simh] DECserver (terminal server) emulation?

[Paul Koning]

> On Apr 13, 2017, at 3:34 AM, Johnny Billquist <bqt at softjar.se> wrote:
> 
> On 2017-04-13 02:27, Paul Koning wrote:
>> 
>>> On Apr 12, 2017, at 2:22 AM, Johnny Billquist <bqt at softjar.se> wrote:
>>> 
>>> The DS500 is a PDP-11, true. But it's also the model that don't have any local storage, and thus uses MOP in way more ways than any other DS, which might be a problem unless you have some machine with a proper MOP implementation.
>>> The MOP server that exists for Unix systems will not do. It only supports booting.
>> 
>> What else do you need?  MOP doesn't do much more than that.  Config data download?
> 
> Actually, it does. MOP can do reading and writing of data to files as well.

Not really.  There's a load protocol and a dump protocol.  Load can reference the load image by ID string if enabled, but that doesn't make it a general file access protocol.

> And it can support terminal traffic. I don't even have the information on how this part of MOP works, all I know is that it does work. In RSX, you have a program called CCR for the terminal traffic (Console Carrier Request I think). RSX-11S systems can also do crashdumps over MOP if they crash.
> 
> I know that you can use CCR on VMS as well, but I don't remember the syntax. Might be some switch to SET HOST.

The console carrier protocol, as well as all the other bits of MOP, are fully documented in the MOP architecture spec.

>> In any case, MOP is a trivial protocol, fixing omissions in an existing MOP implementation is pretty easy.
> 
> Possibly. I don't have all the details.
> 
>> Hm.  mop.py?  That would be nicely portable and easy to create...
> 
> Feel free. :-)

Actually, parts of it (including console carrier) already exist in my Python DECnet stack.  Not yet load/dump, though.

	paul