TMS320F2812

Dear Folks,

I am a M.Sc. student and I need to work with TMS320F2812 for my master. I
am new to DSP. I want to read a high rate ADC (about 50-100 MSPS) samples
by DSP and then process it. I have some questions about that; first, how
should I generate the clock of the ADC by DSP. Should I generate it using
PWM ? If the answer is yes, is it possible to generate a clock frequency in
that speed by TMS320F2812 ? As a final question, Is there any other methods
to make the ADC clock by DSP?

Thanks for your time and consideration. Looking forward to hearing from
you.

Kindest Regards,
Amir

"leomhb" <62505@dsprelated> writes:

> Dear Folks,
>
> I am a M.Sc. student and I need to work with TMS320F2812 for my master. I
> am new to DSP. I want to read a high rate ADC (about 50-100 MSPS) samples
> by DSP and then process it. 

Hi Amir,

That's not happening. Not on a 2812. You'll overload the CPU just
reading data. 

> I have some questions about that; first, how
> should I generate the clock of the ADC by DSP. Should I generate it using
> PWM ? If the answer is yes, is it possible to generate a clock frequency in
> that speed by TMS320F2812 ? As a final question, Is there any other methods
> to make the ADC clock by DSP?

TI has lots of documentation on this family - datasheets on the part,
user's guides, guides on the individual peripherals, etc. Try searching
their site and reading.

>
> Thanks for your time and consideration. Looking forward to hearing from
> you.
>
> Kindest Regards,
> Amir
>
>

-- 
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com

On Wed, 05 Dec 2012 08:32:05 -0600, leomhb wrote:

> Dear Folks,
> 
> I am a M.Sc. student and I need to work with TMS320F2812 for my master.
> I am new to DSP. I want to read a high rate ADC (about 50-100 MSPS)
> samples by DSP and then process it. I have some questions about that;
> first, how should I generate the clock of the ADC by DSP. Should I
> generate it using PWM ? If the answer is yes, is it possible to generate
> a clock frequency in that speed by TMS320F2812 ? As a final question, Is
> there any other methods to make the ADC clock by DSP?
> 
> Thanks for your time and consideration. Looking forward to hearing from
> you.
> 
> Kindest Regards,
> Amir

The only really sensible way to generate the ADC clock is using one of 
the timers, yes.

You should read the data sheet -- you'll find that the timer is clocked 
by the core clock divided by two, and from that you'd figure out that 
yes, your timer will be plenty fast.

-- 
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

On Wed, 05 Dec 2012 09:54:16 -0600, Tim Wescott wrote:

> On Wed, 05 Dec 2012 08:32:05 -0600, leomhb wrote:
> 
>> Dear Folks,
>> 
>> I am a M.Sc. student and I need to work with TMS320F2812 for my master.
>> I am new to DSP. I want to read a high rate ADC (about 50-100 MSPS)
>> samples by DSP and then process it. I have some questions about that;
>> first, how should I generate the clock of the ADC by DSP. Should I
>> generate it using PWM ? If the answer is yes, is it possible to
>> generate a clock frequency in that speed by TMS320F2812 ? As a final
>> question, Is there any other methods to make the ADC clock by DSP?
>> 
>> Thanks for your time and consideration. Looking forward to hearing from
>> you.
>> 
>> Kindest Regards,
>> Amir
> 
> The only really sensible way to generate the ADC clock is using one of
> the timers, yes.
> 
> You should read the data sheet -- you'll find that the timer is clocked
> by the core clock divided by two, and from that you'd figure out that
> yes, your timer will be plenty fast.

Whoops -- strike that.  I thought you meant 100kSPS.  100MSPS doesn't 
even give you time to put the ADC data anywhere, much less do anything 
with it.  That's well into FPGA territory.

-- 
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

"leomhb" <62505@dsprelated> wrote in message 
news:APSdnZ-617N4xyLNnZ2dnUVZ_sGdnZ2d@giganews.com...
> Dear Folks,
>
> I am a M.Sc. student and I need to work with TMS320F2812 for my master. I
> am new to DSP. I want to read a high rate ADC (about 50-100 MSPS) samples
> by DSP and then process it.

50-100 MSPS is completely out of the class of TMS28xx.
Somewhat 10 or may be 20 MSPS would be realistic.

> I have some questions about that; first, how
> should I generate the clock of the ADC by DSP. Should I generate it using
> PWM ? If the answer is yes, is it possible to generate a clock frequency 
> in
> that speed by TMS320F2812 ? As a final question, Is there any other 
> methods
> to make the ADC clock by DSP?

There are timers, there are serial ports, there is CLK_OUT signal. Zillion 
of methods.

Vladimir Vassilevsky
DSP and Mixed Signal Consultant
www.abvolt.com

On Wednesday, December 5, 2012 8:32:05 AM UTC-6, leomhb wrote:
> Dear Folks, I am a M.Sc. student and I need to work with TMS320F2812 for my master. I am new to DSP. I want to read a high rate ADC (about 50-100 MSPS) samples by DSP and then process it. I have some questions about that; first, how should I generate the clock of the ADC by DSP. Should I generate it using PWM ? If the answer is yes, is it possible to generate a clock frequency in that speed by TMS320F2812 ? As a final question, Is there any other methods to make the ADC clock by DSP? Thanks for your time and consideration. Looking forward to hearing from you. Kindest Regards, Amir

You are not going to do 50MHz to 100MHz sampling with a F2812. You may want to consider using an external clock with the external ADC and external memory, controling the start/stop/storage of conversion/data with the F2812, and using the F2812 to read the external memory to do the processing (the F2812 has a 19-bit external interface built in) after the storage time.

On Wednesday, December 5, 2012 8:32:05 AM UTC-6, leomhb wrote:
> Dear Folks, I am a M.Sc. student and I need to work with TMS320F2812 for my master. I am new to DSP. I want to read a high rate ADC (about 50-100 MSPS) samples by DSP and then process it. I have some questions about that; first, how should I generate the clock of the ADC by DSP. Should I generate it using PWM ? If the answer is yes, is it possible to generate a clock frequency in that speed by TMS320F2812 ? As a final question, Is there any other methods to make the ADC clock by DSP? Thanks for your time and consideration. Looking forward to hearing from you. Kindest Regards, Amir

Also, if you get a progarmmable clock/osc (maybe mini circuits?), your program can vary the conversion rate.

You haven't stated whether you are trying to capture a burst of data and 
then process it, or whether you are trying to process 50 -100M samples 
continuously.

If you are making a burst measurement, you could use a SHARC DSP with its 
PDAP interface (FIFO) for data rates to about 50M/s or you could use the 
SHARC ADSP-21469 link ports. Alternatively, you could use an external FIFO 
(which could be implemented by an FPGA or a dedicated device) in front of  
most DSPs. You will also need a low phase jitter clock source.

If you are trying to process continuous data, you are definitely in FPGA 
space. 

Al Clark
www.danvillesignal.com








Randy Yates <yates@digitalsignallabs.com> wrote in
news:87obi8h5of.fsf@randy.site: 

> "leomhb" <62505@dsprelated> writes:
> 
>> Dear Folks,
>>
>> I am a M.Sc. student and I need to work with TMS320F2812 for my master.
>> I am new to DSP. I want to read a high rate ADC (about 50-100 MSPS)
>> samples by DSP and then process it. 
> 
> Hi Amir,
> 
> That's not happening. Not on a 2812. You'll overload the CPU just
> reading data. 
> 
>> I have some questions about that; first, how
>> should I generate the clock of the ADC by DSP. Should I generate it
>> using PWM ? If the answer is yes, is it possible to generate a clock
>> frequency in that speed by TMS320F2812 ? As a final question, Is there
>> any other methods to make the ADC clock by DSP?
> 
> TI has lots of documentation on this family - datasheets on the part,
> user's guides, guides on the individual peripherals, etc. Try searching
> their site and reading.
> 
>>
>> Thanks for your time and consideration. Looking forward to hearing from
>> you.
>>
>> Kindest Regards,
>> Amir
>>
>>
> 

>On Wednesday, December 5, 2012 8:32:05 AM UTC-6, leomhb wrote:
>> Dear Folks, I am a M.Sc. student and I need to work with TMS320F2812 for
=
>my master. I am new to DSP. I want to read a high rate ADC (about 50-100
MS=
>PS) samples by DSP and then process it. I have some questions about that;
f=
>irst, how should I generate the clock of the ADC by DSP. Should I generate
=
>it using PWM ? If the answer is yes, is it possible to generate a clock
fre=
>quency in that speed by TMS320F2812 ? As a final question, Is there any
oth=
>er methods to make the ADC clock by DSP? Thanks for your time and
considera=
>tion. Looking forward to hearing from you. Kindest Regards, Amir
>
>You are not going to do 50MHz to 100MHz sampling with a F2812. You may
want=
> to consider using an external clock with the external ADC and external
mem=
>ory, controling the start/stop/storage of conversion/data with the F2812,
a=
>nd using the F2812 to read the external memory to do the processing (the
F2=
>812 has a 19-bit external interface built in) after the storage time.
>

Dear,

I am sorry because of my incomplete explanation. Of course, I am using an
external ADC (Analog AD9283), and I want to controlling the clock of the
AD9283 by TMS320F2812 and also, read the samples and save them into the
internal memory of the DSP. Is there enough time to read the data from the
ADC and then saving them to internal memory (DSP) in such speed?

Thanks 

"leomhb" <62505@dsprelated> writes:

>>On Wednesday, December 5, 2012 8:32:05 AM UTC-6, leomhb wrote:
>>> Dear Folks, I am a M.Sc. student and I need to work with TMS320F2812 for
> =
>>my master. I am new to DSP. I want to read a high rate ADC (about 50-100
> MS=
>>PS) samples by DSP and then process it. I have some questions about that;
> f=
>>irst, how should I generate the clock of the ADC by DSP. Should I generate
> =
>>it using PWM ? If the answer is yes, is it possible to generate a clock
> fre=
>>quency in that speed by TMS320F2812 ? As a final question, Is there any
> oth=
>>er methods to make the ADC clock by DSP? Thanks for your time and
> considera=
>>tion. Looking forward to hearing from you. Kindest Regards, Amir
>>
>>You are not going to do 50MHz to 100MHz sampling with a F2812. You may
> want=
>> to consider using an external clock with the external ADC and external
> mem=
>>ory, controling the start/stop/storage of conversion/data with the F2812,
> a=
>>nd using the F2812 to read the external memory to do the processing (the
> F2=
>>812 has a 19-bit external interface built in) after the storage time.
>>
>
> Dear,
>
> I am sorry because of my incomplete explanation. Of course, I am using an
> external ADC (Analog AD9283), and I want to controlling the clock of the
> AD9283 by TMS320F2812 and also, read the samples and save them into the
> internal memory of the DSP. Is there enough time to read the data from the
> ADC and then saving them to internal memory (DSP) in such speed?

As Al Clark pointed out, it depends on whether your intent is to capture
a continuous stream of samples or only a block of samples (e.g., N=64
samples) and then process. In the latter case you would presumably be
doing a "capture N, process, capture N, process, ..." procedure, so your
capture would not be continuous.

The F2812 won't be fast enough to capture samples continuously at 50
MHz. Or rather, you wouldn't have many cycles left to do anything with
the data once it's captured. I believe the top clock speed for the
device is 200 MHz, so that only leaves you 4 cycles per sample - hardly
enough to read it from a port and store it somewhere.
-- 
Randy Yates
Digital Signal Labs
http://www.digitalsignallabs.com