Hi,

On Fri, Mar 28, 2014 at 3:07 AM, Stuart Brady <sdb@zubnet.me.uk> wrote:
On Thu, Mar 27, 2014 at 10:04:13PM +0000, Stuart Brady wrote:
> Hi Jon,
>
> Just wondering if you could help clear up a question regarding both the
> ZX-State format and the behaviour of the Z80, please?
>
> Reading the ZX-State specification, I'm wondering if Fuse has an
> incorrect implementation of ZXSTZF_HALTED:
>
>    http://www.spectaculator.com/docs/zx-state/z80regs.shtml
>
> Fuse only advances PC once the interrupt is delivered, and keeps fetching
> from the address containing the HALT opcode over and over until then.
> I understand that it should ignore the opcodes returned, but what address
> should it be fetching from? — that of the HALT opcode or the one beyond?

An extra data point here:  in my copy of "Almost everything about... the
Z80 microprocessor"[1] by Miklos Patrubany, page 193, the simulator
fetches from the opcode _after_ the HALT.

The Z80 simulator therein is emulated by the my-amic[2] project, if anyone
wants to try it out.  I haven't yet.


Cheers,
Alex


[1] mine is in Romanian, but has an English summary with this title.
[2] http://code.google.com/p/my-amic/