[Simh] Custom PC formatting

[Mark Pizzolato - Info Comm]

On Sunday, October 06, 2013 at 7:54 AM, Peter Onion wrote:
> I'm just having a look at porting an existing emulation into the simh
> framework.
> 
> My first problem is that there seems to be no way to provide a custom
> "print" routine for the value of the PC.
> 
> Why do I need one ?
> 
> Because the least significant bit of the Sequence Control Register in my
> machine has the value "half" as there are 2 instructions in each word.
> 
> I'm sure I'll have lots more questions soon !

Hi Peter,

Actually there is a custom way to display the contents of any simh device register.

This is available on the most recent simh codebase on github:  https://github.com/simh/simh

In the latest code, registers can have an optional bit field description for the register.  The bitfields can be formatted in a variety of flexible ways.

An example of a register which uses a custom formatting paradigm is the PSL register definition in the VAX CPU module at https://github.com/simh/simh/blob/master/VAX/vax_cpu.c

FYI a zip of the current code base is available at: https://github.com/simh/simh/archive/master.zip

Please come back with more questions as you encounter them.

- Mark