GDB front-end for SimH

[Maciej W. Rozycki]

On Tue, 24 Apr 2018, Paul Koning via cctalk wrote:

> One drawback is that there aren't all that many SIMH architectures that 
> have GDB support.  VAX does, and Alpha; that's about it.  I don't know 
> how hard it is to do a basic platform in GDB, probably not all that 
> difficult.  At least for machines like PDP-11.  One's complement might 
> be harder (PDP-1), never mind things like the IBM 1620...  :-)

 You need target BFD and libopcodes support for a GDB port to be possible.  
There is such support already present for PDP-11, so wiring in GDB parts 
should be straightforward.  A remote protocol stub for SimH should also be 
easy to write as you don't need all the fancy stuff and GDB will be happy 
to work with just the `?', `G', `M', `c', `g', `m' request packets and the 
`S' stop reply packet implemented.  The rest is optional.

 HTH,

  Maciej