Reply by Steve Holle ●July 2, 20042004-07-02
At 11:37 PM 7/1/2004, andor_bariska wrote:
>Steve Holle wrote:
>...
> > Has anyone out there dealt with sport signal termination on the
> > 065L successfully?
>
>Steve,
>
>have you looked at ADI's EE 74 which deals with the conditioning of
>SPORT signals?

We have looked at this ap note and although it was helpful, what eventually
did the trick was putting an 74xxx08 buffer on the TCLK0 and RFS0 lines
from the card driving those signals. The data sheet is pretty vague about
drive capability and what kind of buffers to use. The data lines cannot be
buffered, of course, since we have the DR and DT lines tied together. We
are a little worried about margins on the data lines since we can't buffer
them.

>Regards,
>Andor >
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Steve Holle
Link Communications, Inc.
1035 Cerise Rd.
Billings, MT 59101



Reply by andor_bariska ●July 2, 20042004-07-02
Steve Holle wrote:
...
> Has anyone out there dealt with sport signal termination on the
> 065L successfully?

Steve,

have you looked at ADI's EE 74 which deals with the conditioning of
SPORT signals?

Regards,
Andor


Reply by Steve Holle ●July 1, 20042004-07-01
We have a system with a backplane with five slots for ADSP-21065L DSP's
based custom cards. Each DSP card has SPORT 0 DR0A and DT0A tied together.
TCLK0, RFS0, and the common DT signals are then each run through a 33ohm
series to the backplane bus.

The problem is that we are having significant noise problems. One slot in
our back plane seems to have problems on the TCLK line as the audio
crackles until we connect a scope probe to the TCLK line.

We have tried various resistor and capacitor combinations which only seem
to make the problem worse. We have noted item 21 in the Anomaly list but
are not sure how to proceed to fix the problem. Has anyone out there dealt
with sport signal termination on the 065L successfully? If so, what was
your solution, if you wouldn't mind sharing it.

Thanks for your help.

Steve Holle
Link Communications, Inc.
1035 Cerise Rd.
Billings, MT 59101