Help on different types of emulators

"Jim Thomas" <jthomas@bittware.com> wrote in message
news:1012cf18ujusu63@corp.supernews.com...
> Fred Marshall wrote:
> > I think I get it now.  Let me try to parrot back:
> >
> > "An emulator in today's terms most likely means a JTAG emulator which
is:
> > - a physical JTAG interface on a board or on a processor chip that
allows
> > getting at registers, memory, interrupts, etc. on the real processor
> > - an external software interface that allows one to monitor and control
what
> > the processor is doing
> > It can be used as a monitor and it can be used as a debugger."
> >
> > Am I getting close?
>
> Yup.  I'd say you nailed it.

Thanks folks!  Now all I have to do is make it work!
I bought the ADSP-BF533 EZ-Kit Lite.
Now I guess I'm going to have to get to work with it.

Fred

Fred:

I would add one thing. JTAG was devised as a testability enhancement to
chips. However, though many chips support the JTAG standard, most of them
also include boundary registers not part of the JTAG standard. In these
additional registers, accessible via JTAG, the chips can actually be forced
to execute instructions, that were not part of their own code, but forced in
via JTAG.

Therein lies the fine line. The chips that allow forced execution of
externally generated instrunctions (not from their own prom/ram/whatever)
via JTAG, allow "emulation" in the full sense of the word--a different
processor can be used to generated the opcodes that will be executed on the
target processor. Now, it may not happen in real-time, but it is "emulation"
via JTAG.

Jim



"Jim Thomas" <jthomas@bittware.com> wrote in message
news:1012cf18ujusu63@corp.supernews.com...
> Fred Marshall wrote:
> > I think I get it now.  Let me try to parrot back:
> >
> > "An emulator in today's terms most likely means a JTAG emulator which
is:
> > - a physical JTAG interface on a board or on a processor chip that
allows
> > getting at registers, memory, interrupts, etc. on the real processor
> > - an external software interface that allows one to monitor and control
what
> > the processor is doing
> > It can be used as a monitor and it can be used as a debugger."
> >
> > Am I getting close?
>
> Yup.  I'd say you nailed it.
>
> --
> Jim Thomas            Principal Applications Engineer  Bittware, Inc
> jthomas@bittware.com  http://www.bittware.com          (703) 779-7770
> The problem with the future is that it keeps turning into the present -
> Hobbes
>

"Jim Gort" <jgort@comcast.net> wrote in message
news:n0JQb.146429$na.242071@attbi_s04...
> Fred:
>
> I would add one thing. JTAG was devised as a testability enhancement to
> chips. However, though many chips support the JTAG standard, most of them
> also include boundary registers not part of the JTAG standard. In these
> additional registers, accessible via JTAG, the chips can actually be
forced
> to execute instructions, that were not part of their own code, but forced
in
> via JTAG.
>
> Therein lies the fine line. The chips that allow forced execution of
> externally generated instrunctions (not from their own prom/ram/whatever)
> via JTAG, allow "emulation" in the full sense of the word--a different
> processor can be used to generated the opcodes that will be executed on
the
> target processor. Now, it may not happen in real-time, but it is
"emulation"
> via JTAG.
>
> Jim

Thanks Jim.  You never did tell me if you were the Jim Gort who worked at
PDI....

Fred