Vladimir,
On 4/26/2011 10:25 AM, vterrap wrote:
>
> Mike,
>
> You are right. DSK reference said that it has asynchronous outputs
> only. I suppose synchronous memory can still be implemented as ECLKOUT
> output is present. Also I was referring to DSK, not to the C6455 by
> itself.
>
FYI - the phrase "the specifics of the 6455 EMIF external logic and
board layout" was intended to refer to the DSK Daughtercard interface.
mikedunn
> Vladimir
>
> --- In c... , mikedunn
> wrote:
> >
> > Vladimir,
> >
> > On 4/25/2011 9:10 AM, vterrap wrote:
> > >
> > > Jeff and Lee-Mort,
> > >
> > > First of all to answer your question Jeff: according to the 6455 DSK
> > > manual EMIF connector only provides asynchronous access. I am not
> > > quite sure of that, but if this is indeed true, the fastest clock you
> > > can get is when HOLD = STROBE = SETUP = 1 ECLKOUT, and then there
> is a
> > > minimum turn around time of 2 ECLKOUTs. Therefore with the max
> > > ECLCKOUT of 150 MHz, you can get only 30 MHz asynchronous memory
> > > clock. If synchronous memory can be used, despite what manual says,
> > > then max clock can be up to 166 MHz.
> > >
> >
> > FYI-The "synchronous memory cannot be used" is a half truth.
> Synchronous
> > Dynamic RAMs cannot be used - I'm not sure if you misread it or it
was
> > printed wrong.
> > I don't know the specifics of the 6455 EMIF external logic and board
> > layout, but I would expect it to support SRAMs at 90-133 Mhz.
> >
> > mikedunn
> > >
> > >
> > > Also, I made an error when I made a post. I made EMIF to DAC
> > > connection, not the EMIF to ADC. I have connected the ADC to the HPI
> > > port using an FPGA as pre-processing and control module. I think that
> > > ADC to EMIF is still easier to do and will not require anything
> extra.
> > > First of all, I have seen application notes and projects online that
> > > talk about EMIF to ADC connection. Second, drawback of EMIF is
> that it
> > > does not have an event that can be used by EDMA. Therefore, a timer
> > > event needs to be used to transfer ADC readings into the memory via
> > > EDMA. It is important to make sure timer events and the memory
> writes,
> > > are synchronized. Another option is to connect clock from memory
> > > writes, to the GPIO pin, and use that as the EDMA event.
> > >
> > > Hope this adds a little more help. Also I am going to see if I can
> > > post some of my thesis and code work.
> > >
> > > Vladimir
> > >
> > >
> >
parallel signal from adc to tms320c6455 dsk
Started by ●April 21, 2011
Reply by ●April 26, 20112011-04-26
