[Simh] Bug in pdp11 simulator?

[Mark Pizzolato - Info Comm]

Bob,

Jordi's idle issue is with the released v3.9-0 version.

I'm not a PDP11 user, and I know next to nothing about PDP11 OSes.

Therefore, I really can't address this issue with authority, however I looked at the running system when this happens. 

His ini file does the following:

  set pclk enable
  set clk 60
  set pclk 60

Before he boots the clocks look like this:
                    sim> sh clk
                    CLK, 60Hz, address=17777546-17777547, vector=100
                    sim> sh pclk
                    PCLK, address=17772540-17772545, vector=104, 60 Hz
                    sim> b rp0

                    RSTS/E requires a clock, enabling KW11-L at 60Hz.
                    KW11-L doesn't work.

Thinking this looks strange, I hit Ctrl-E

                    Simulation stopped, PC: 062454 (CMP R5,(R0))
                    sim> sh clk
                    CLK, 50Hz, address=17777546-17777547, vector=100
                    sim> sh pclk
                    PCLK, address=17772540-17772545, vector=104, 60 Hz

I don't know what the message means, but the clock rate seems to have changed from 60hz to 50hz.  It would seem that this could cause these two clocks to have strange event timing interactions which could cause the logic in sim_idle to not actually idle....

I have no idea where to go from here.

- Mark

On Friday, May 04, 2012, at 3:25 AM, Jordi Guillaumes i Pons wrote:
> Hi everyone.
> 
> Congratulations to Bob, Mark and everyone involved in this new release.
> The networking new features are really outstanding.
> 
> Unfortunately, I've jumped in whats seems to be a bug, present in the final
> release but, weird enough, not apreciable in the 3.9-0-rc1 branch.
> When I try to boot RSTS/E V10 using a pdp11 emulator built from the git
> repository the simulator hangs and I have to kill the process. When i use a
> binary built from the rc1 branch, it works (but it ignores the idle detection in
> RSTS, works in RSX...).
> 
> I'm compiling SIMH under linux amd64. If this is a real bug and not a stupid
> mistake from my part please tell me what can I do to help to fix it.
> 
> My config file, for reference, is attached to this email (I hope the list
> processor won't strip it).
> 
>