Re: Tempest Tech?? (Using the Z input on scope with Tempest)

Hmm.. Lets give this a second thought:

If the vector drawn should be RED, and you use an OR port to BLANK
the trace, the BLUE vector would become BLACK (blanked), because the
BLUE (and the green)
output will be blanked (and thus the output of the OR would blank the
vector on a
monochrome display).

The (retrace) vectors should only be black when ALL of the outputs are
blanked, so
you should use an AND port (or NAND, if your scope has an inverted Z
input).

Am I right or do I forget something?

Cya !

Joel Rosenzweig wrote:
>
> Matt,
>
> Scott's suggestion is OK, but there's a little more the to story. If you
> use only one of the RGB signals as your Z input, you will only see vectors
> that use the corresponding color gun to greate the vector. That is, if you
> hook up only your B gun and Tempest draws a magenta vector, you'll see it
> because the B and R guns are used to create magenta. But if Tempest draws a
> green vector you'll miss it because your scope is blanking on everything
> except B gun activity.
>
> In order to see all of the vectors, you must OR all three signals together.
> If you scope needs an inverted input on Z, remember to invert the output.
> That is, use a 3 input NOR gate or logically equivalent circuit.
>
> Joel-
>
> >Matt,
> > Use any one of the three RGB signals as the z input to a scope. Tempest
> >has a mono Z out on Q10(i think) Q10 combines the three RGB signals into
> >one mono signal, perfect for an o-scope.
> >
> >-Scott
> >
> >PS please re-post this to the VL if it doesn't show-up. My VL posts don't
> >bounce, but they never appear on the VL.
> >
> >At 04:38 PM 12/6/99 -0800, Matt Rossiter - Verio Southern California wrote:
> >>You can also hook the board up to an oscilloscope if it has an XY mode.
> >>This is how I test all my vector boards from home.
> >>
> >>Of course, this brings up another question I have. I hope I'm not asking
> >>too many questions. How does one hook up the Z or blanking circuit to the
> >>oscilloscope? I know with black and white vector games there's a Z
> >>hookup, but I can't see any for the color vector games but I do see X and
> >>Y Inverts. Could someone explain this to me?
> >>
> >>
> >>Matt
> >
> >--
> >Scott Swazey QUALCOMM Incorporated Work: (858) 657-2419
> >mailto:sswazey@qualcomm.com V-213G Pager:(858) 683-5210
> >
> >
Received on Tue Dec 7 13:55:02 1999