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Difference between C6416 and DM642

Started by qing_lee73 August 11, 2004
Hi group,

Here comes my second question today: what is the difference between
DM642 and C6416?

I know there is coprocessor that deals with entropy coding and some
additional peripherals in DM642. But I want to know how much it can
help to improve the performance? And is there any other difference
between DM642 and C6416 that can help improve performance?

Thanks in advance!!

Best regards,
Quentin



There is no coprocessor which deals with entory coding
in DM642. You might be confusing it with DM270 etc.
There are additional video ports, but they won't be of
any help in performance as such. In fact performance
in DM642 should be lower than C6416 since it has only
256K L2 compared to 1M L2 in C6416. Regards
Piyush

--- qing_lee73 <> wrote:

> Hi group,
>
> Here comes my second question today: what is the
> difference between
> DM642 and C6416?
>
> I know there is coprocessor that deals with entropy
> coding and some
> additional peripherals in DM642. But I want to know
> how much it can
> help to improve the performance? And is there any
> other difference
> between DM642 and C6416 that can help improve
> performance?
>
> Thanks in advance!!
>
> Best regards,
> Quentin >
>
> _____________________________________
> Note: If you do a simple "reply" with your email
> client, only the author of this message will receive
> your answer. You need to do a "reply all" if you
> want your answer to be distributed to the entire
> group.
>
> _____________________________________
> About this discussion group:
>
> To Join: Send an email to > To Post: Send an email to
>
> To Leave: Send an email to > Archives: http://www.yahoogroups.com/group/c6x
>
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>
> Yahoo! Groups Links >
>


=====
**************************************
And---"A blind Understanding!" Heav'n replied.

Piyush Kaul
http://www.geocities.com/piyushkaul
__________________________________


Piyush-

> There is no coprocessor which deals with entory coding
> in DM642. You might be confusing it with DM270 etc.
> There are additional video ports, but they won't be of
> any help in performance as such. In fact performance
> in DM642 should be lower than C6416 since it has only
> 256K L2 compared to 1M L2 in C6416.

A biggie: DM642 has EMAC peripheral. None of the C641x devices have that one.

-Jeff

> --- qing_lee73 <> wrote:
>
> > Hi group,
> >
> > Here comes my second question today: what is the
> > difference between
> > DM642 and C6416?
> >
> > I know there is coprocessor that deals with entropy
> > coding and some
> > additional peripherals in DM642. But I want to know
> > how much it can
> > help to improve the performance? And is there any
> > other difference
> > between DM642 and C6416 that can help improve
> > performance?
> >
> > Thanks in advance!!
> >
> > Best regards,
> > Quentin





EMAC might be very useful . But how does it effect the
performance?? --- Jeff Brower <> wrote:

> Piyush-
>
> > There is no coprocessor which deals with entory
> coding
> > in DM642. You might be confusing it with DM270
> etc.
> > There are additional video ports, but they won't
> be of
> > any help in performance as such. In fact
> performance
> > in DM642 should be lower than C6416 since it has
> only
> > 256K L2 compared to 1M L2 in C6416.
>
> A biggie: DM642 has EMAC peripheral. None of the
> C641x devices have that one.
>
> -Jeff
>
> > --- qing_lee73 <> wrote:
> >
> > > Hi group,
> > >
> > > Here comes my second question today: what is the
> > > difference between
> > > DM642 and C6416?
> > >
> > > I know there is coprocessor that deals with
> entropy
> > > coding and some
> > > additional peripherals in DM642. But I want to
> know
> > > how much it can
> > > help to improve the performance? And is there
> any
> > > other difference
> > > between DM642 and C6416 that can help improve
> > > performance?
> > >
> > > Thanks in advance!!
> > >
> > > Best regards,
> > > Quentin > _____________________________________
> Note: If you do a simple "reply" with your email
> client, only the author of this message will receive
> your answer. You need to do a "reply all" if you
> want your answer to be distributed to the entire
> group.
>
> _____________________________________
> About this discussion group:
>
> To Join: Send an email to > To Post: Send an email to
>
> To Leave: Send an email to > Archives: http://www.yahoogroups.com/group/c6x
>
> Other Groups: http://www.dsprelated.com
>
> Yahoo! Groups Links >
>


=====
**************************************
And---"A blind Understanding!" Heav'n replied.

Piyush Kaul
http://www.geocities.com/piyushkaul
__________________________________


DM642 has dedictaed video ports to allow for multi channel decoding.
It has a 256K L2 memory. DM642 is intended for video and streaming
video applications.

Regds
JS >piyush kaul wrote:
>
> EMAC might be very useful . But how does it effect the
> performance??
>
> --- Jeff Brower <> wrote:
>
> > Piyush-
> >
> > > There is no coprocessor which deals with entory
> > coding
> > > in DM642. You might be confusing it with DM270
> > etc.
> > > There are additional video ports, but they won't
> > be of
> > > any help in performance as such. In fact
> > performance
> > > in DM642 should be lower than C6416 since it has
> > only
> > > 256K L2 compared to 1M L2 in C6416.
> >
> > A biggie: DM642 has EMAC peripheral. None of the
> > C641x devices have that one.
> >
> > -Jeff
> >
> > > --- qing_lee73 <> wrote:
> > >
> > > > Hi group,
> > > >
> > > > Here comes my second question today: what is the
> > > > difference between
> > > > DM642 and C6416?
> > > >
> > > > I know there is coprocessor that deals with
> > entropy
> > > > coding and some
> > > > additional peripherals in DM642. But I want to
> > know
> > > > how much it can
> > > > help to improve the performance? And is there
> > any
> > > > other difference
> > > > between DM642 and C6416 that can help improve
> > > > performance?
> > > >
> > > > Thanks in advance!!
> > > >
> > > > Best regards,
> > > > Quentin
> >
> >
> > _____________________________________
> > Note: If you do a simple "reply" with your email
> > client, only the author of this message will receive
> > your answer. You need to do a "reply all" if you
> > want your answer to be distributed to the entire
> > group.
> >
> > _____________________________________
> > About this discussion group:
> >
> > To Join: Send an email to
> >
> >
> > To Post: Send an email to
> >
> > To Leave: Send an email to
> >
> >
> > Archives: http://www.yahoogroups.com/group/c6x
> >
> > Other Groups: http://www.dsprelated.com
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
>
> =====
> **************************************
> And---"A blind Understanding!" Heav'n replied.
>
> Piyush Kaul
> http://www.geocities.com/piyushkaul > __________________________________
>
> _____________________________________
> Note: If you do a simple "reply" with your email client, only the author of
this message will receive your answer. You need to do a "reply all" if you want
your answer to be distributed to the entire group.
>
> _____________________________________
> About this discussion group:
>
> To Join: Send an email to
>
> To Post: Send an email to
>
> To Leave: Send an email to
>
> Archives: http://www.yahoogroups.com/group/c6x
>
> Other Groups: http://www.dsprelated.com
>
> Yahoo! Groups Links >
>




Piyush-

> EMAC might be very useful . But how does it effect the
> performance??

By not using McBSP or HPI to send data to other devices or other processors? By
having a a more practical, easier-to-connect alternative than UTOPIA ?

Other than memory/cache, I/O bottleneck is the number 2 factor affecting
performance. Would you use a processor in a video application *without* a
network
connection?

-Jeff

> --- Jeff Brower <> wrote:
>
> > Piyush-
> >
> > > There is no coprocessor which deals with entory
> > coding
> > > in DM642. You might be confusing it with DM270
> > etc.
> > > There are additional video ports, but they won't
> > be of
> > > any help in performance as such. In fact
> > performance
> > > in DM642 should be lower than C6416 since it has
> > only
> > > 256K L2 compared to 1M L2 in C6416.
> >
> > A biggie: DM642 has EMAC peripheral. None of the
> > C641x devices have that one.
> >
> > -Jeff
> >
> > > --- qing_lee73 <> wrote:
> > >
> > > > Hi group,
> > > >
> > > > Here comes my second question today: what is the
> > > > difference between
> > > > DM642 and C6416?
> > > >
> > > > I know there is coprocessor that deals with
> > entropy
> > > > coding and some
> > > > additional peripherals in DM642. But I want to
> > know
> > > > how much it can
> > > > help to improve the performance? And is there
> > any
> > > > other difference
> > > > between DM642 and C6416 that can help improve
> > > > performance?
> > > >
> > > > Thanks in advance!!
> > > >
> > > > Best regards,
> > > > Quentin




Jeff,
You too are right, but maybe we need to define
performance first. Perhaps we are using different
definitions of performance.

I used the word performance to indicate MCPS count for
the codec part. And my contention is that this figure
is going to be better(lower) in C6416 rather that
DM642. This is also supported by my experience.

You seem to use "performance" for overall usability
and capacity of the entire system (application). I
would acknowledge that. The EMAC and Video ports are
very useful and maybe necessary too in some video
applications.

But it looks like the OP wanted information on the
effect on performance figures for the codec part,
hence my answer.

Regards
Piyush
--- Jeff Brower <> wrote:

> Piyush-
>
> > EMAC might be very useful . But how does it effect
> the
> > performance??
>
> By not using McBSP or HPI to send data to other
> devices or other processors? By
> having a a more practical, easier-to-connect
> alternative than UTOPIA ?
>
> Other than memory/cache, I/O bottleneck is the
> number 2 factor affecting
> performance. Would you use a processor in a video
> application *without* a network
> connection?
>
> -Jeff
>
> > --- Jeff Brower <> wrote:
> >
> > > Piyush-
> > >
> > > > There is no coprocessor which deals with
> entory
> > > coding
> > > > in DM642. You might be confusing it with DM270
> > > etc.
> > > > There are additional video ports, but they
> won't
> > > be of
> > > > any help in performance as such. In fact
> > > performance
> > > > in DM642 should be lower than C6416 since it
> has
> > > only
> > > > 256K L2 compared to 1M L2 in C6416.
> > >
> > > A biggie: DM642 has EMAC peripheral. None of
> the
> > > C641x devices have that one.
> > >
> > > -Jeff
> > >
> > > > --- qing_lee73 <> wrote:
> > > >
> > > > > Hi group,
> > > > >
> > > > > Here comes my second question today: what is
> the
> > > > > difference between
> > > > > DM642 and C6416?
> > > > >
> > > > > I know there is coprocessor that deals with
> > > entropy
> > > > > coding and some
> > > > > additional peripherals in DM642. But I want
> to
> > > know
> > > > > how much it can
> > > > > help to improve the performance? And is
> there
> > > any
> > > > > other difference
> > > > > between DM642 and C6416 that can help
> improve
> > > > > performance?
> > > > >
> > > > > Thanks in advance!!
> > > > >
> > > > > Best regards,
> > > > > Quentin
>


=====
**************************************
And---"A blind Understanding!" Heav'n replied.

Piyush Kaul
http://www.geocities.com/piyushkaul
__________________________________



Piyush-

> You too are right, but maybe we need to define
> performance first. Perhaps we are using different
> definitions of performance.
>
> I used the word performance to indicate MCPS count for
> the codec part. And my contention is that this figure
> is going to be better(lower) in C6416 rather that
> DM642. This is also supported by my experience.
>
> You seem to use "performance" for overall usability
> and capacity of the entire system (application). I
> would acknowledge that. The EMAC and Video ports are
> very useful and maybe necessary too in some video
> applications.
>
> But it looks like the OP wanted information on the
> effect on performance figures for the codec part,
> hence my answer.

I agree. I think Quentin got a good idea of the tradeoffs and struggle involved
in
figuring out which device to use :-)

-Jeff

> --- Jeff Brower <> wrote:
>
> > Piyush-
> >
> > > EMAC might be very useful . But how does it effect
> > the
> > > performance??
> >
> > By not using McBSP or HPI to send data to other
> > devices or other processors? By
> > having a a more practical, easier-to-connect
> > alternative than UTOPIA ?
> >
> > Other than memory/cache, I/O bottleneck is the
> > number 2 factor affecting
> > performance. Would you use a processor in a video
> > application *without* a network
> > connection?
> >
> > -Jeff
> >
> > > --- Jeff Brower <> wrote:
> > >
> > > > Piyush-
> > > >
> > > > > There is no coprocessor which deals with
> > entory
> > > > coding
> > > > > in DM642. You might be confusing it with DM270
> > > > etc.
> > > > > There are additional video ports, but they
> > won't
> > > > be of
> > > > > any help in performance as such. In fact
> > > > performance
> > > > > in DM642 should be lower than C6416 since it
> > has
> > > > only
> > > > > 256K L2 compared to 1M L2 in C6416.
> > > >
> > > > A biggie: DM642 has EMAC peripheral. None of
> > the
> > > > C641x devices have that one.
> > > >
> > > > -Jeff
> > > >
> > > > > --- qing_lee73 <> wrote:
> > > > >
> > > > > > Hi group,
> > > > > >
> > > > > > Here comes my second question today: what is
> > the
> > > > > > difference between
> > > > > > DM642 and C6416?
> > > > > >
> > > > > > I know there is coprocessor that deals with
> > > > entropy
> > > > > > coding and some
> > > > > > additional peripherals in DM642. But I want
> > to
> > > > know
> > > > > > how much it can
> > > > > > help to improve the performance? And is
> > there
> > > > any
> > > > > > other difference
> > > > > > between DM642 and C6416 that can help
> > improve
> > > > > > performance?
> > > > > >
> > > > > > Thanks in advance!!
> > > > > >
> > > > > > Best regards,
> > > > > > Quentin




I think the Video Ports in the DM642, with their 'glueless' interface
and scaling / resampling features, will save a lot of time for the
codecs. Also, do I understand right that the demultiplexing and
packing of component data (Y, U, V) into separate buffers is
available only in the DM642 ? This is a huge saver particularly in
combination with the scaling feature since it will save a big amount
of EDMA bandwidth, because almost all codecs operate on 'planar' YUV
rather than interleaved.

Regards
~ka

--- In , piyush kaul <piyushkaul@y...> wrote:
> Jeff,
> You too are right, but maybe we need to define
> performance first. Perhaps we are using different
> definitions of performance.
>
> I used the word performance to indicate MCPS count for
> the codec part. And my contention is that this figure
> is going to be better(lower) in C6416 rather that
> DM642. This is also supported by my experience.
>
> You seem to use "performance" for overall usability
> and capacity of the entire system (application). I
> would acknowledge that. The EMAC and Video ports are
> very useful and maybe necessary too in some video
> applications.
>
> But it looks like the OP wanted information on the
> effect on performance figures for the codec part,
> hence my answer.
>
> Regards
> Piyush
> --- Jeff Brower <jbrower@s...> wrote:
>
> > Piyush-
> >
> > > EMAC might be very useful . But how does it effect
> > the
> > > performance??
> >
> > By not using McBSP or HPI to send data to other
> > devices or other processors? By
> > having a a more practical, easier-to-connect
> > alternative than UTOPIA ?
> >
> > Other than memory/cache, I/O bottleneck is the
> > number 2 factor affecting
> > performance. Would you use a processor in a video
> > application *without* a network
> > connection?
> >
> > -Jeff
> >
> > > --- Jeff Brower <jbrower@s...> wrote:
> > >
> > > > Piyush-
> > > >
> > > > > There is no coprocessor which deals with
> > entory
> > > > coding
> > > > > in DM642. You might be confusing it with DM270
> > > > etc.
> > > > > There are additional video ports, but they
> > won't
> > > > be of
> > > > > any help in performance as such. In fact
> > > > performance
> > > > > in DM642 should be lower than C6416 since it
> > has
> > > > only
> > > > > 256K L2 compared to 1M L2 in C6416.
> > > >
> > > > A biggie: DM642 has EMAC peripheral. None of
> > the
> > > > C641x devices have that one.
> > > >
> > > > -Jeff
> > > >
> > > > > --- qing_lee73 <qing_lee73@y...> wrote:
> > > > >
> > > > > > Hi group,
> > > > > >
> > > > > > Here comes my second question today: what is
> > the
> > > > > > difference between
> > > > > > DM642 and C6416?
> > > > > >
> > > > > > I know there is coprocessor that deals with
> > > > entropy
> > > > > > coding and some
> > > > > > additional peripherals in DM642. But I want
> > to
> > > > know
> > > > > > how much it can
> > > > > > help to improve the performance? And is
> > there
> > > > any
> > > > > > other difference
> > > > > > between DM642 and C6416 that can help
> > improve
> > > > > > performance?
> > > > > >
> > > > > > Thanks in advance!!
> > > > > >
> > > > > > Best regards,
> > > > > > Quentin
> > =====
> **************************************
> And---"A blind Understanding!" Heav'n replied.
>
> Piyush Kaul
> http://www.geocities.com/piyushkaul >
> __________________________________
>





Piyush wrote :
> I used the word performance to indicate MCPS count for
> the codec part. And my contention is that this figure
> is going to be better(lower) in C6416 rather that
> DM642. This is also supported by my experience.

This is very depending on the algorithm.
In general case, you are right that having more internal
memory helps getting best performance.
At least it helps getting performance with less effort.

In that sense, our codecs softwares gets same performances
on DM642 and C6416 using 128KB cache / 128KB ISRAM.

Another point to take into account for the performance
is that C6416 is available for mew months in 720MHz
and 1GHz whereas DM642 at 720 is only recently announced
as available (or to be soon).

The tradeoff of C6416 is the overall board price (if this
is important for you :)
+ more expensive DSP (for same performance)
+ need for FPGA to handle video interface (which are on-chip
on DM642)
+ need for external EMAC if network is required (also on chip
on DM642)

Note that on DM642 EMAC and PCI are exclusive.

Jeff wrote :
> DM642 has EMAC peripheral. None of the C641x devices have that one.
C6412 have but it is not a real competitor to DM642 for vieo apps.

Jean-Michel. Jean-Michel.