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Processing Time in TI eZdsp F2812

Started by vickykulkarni March 30, 2006
Hi

I have a question regarding the flow of my code. I am oversampling my
input signal using the ADC at a rate 3.125 MHz. I have 2 inputs & am using
simultaneous sampling. I am using the adcseqovdtest code of TI as a
framework. So I have 16 samples from the ADC Result registers. My question
is with sampling rate of 3.125 and clock frequency of 150 MHz, I have
(150/3.125) 48 instructions per sample to do signal processing right? So
if i process each sample before reading the next sample, will that work in
real time? The code is 

fir.input=( (AdcRegs.ADCRESULT0)>>4); 
fir.calc(&fir);	 
output=fir.output;

fir.input=( (AdcRegs.ADCRESULT1)>>4);
fir.calc(&fir);	 
output=fir.output;

fir.input=( (AdcRegs.ADCRESULT2)>>4);
fir.calc(&fir);	 
output=fir.output;
......etc for all other result registers.

Any help is highly appreciated. Thanks.

Vik
On Thu, 30 Mar 2006 11:33:48 -0600, "vickykulkarni"
<vickykulkarni@hotmail.com> wrote in comp.dsp:

> Hi > > I have a question regarding the flow of my code. I am oversampling my > input signal using the ADC at a rate 3.125 MHz. I have 2 inputs & am using > simultaneous sampling. I am using the adcseqovdtest code of TI as a > framework. So I have 16 samples from the ADC Result registers. My question > is with sampling rate of 3.125 and clock frequency of 150 MHz, I have > (150/3.125) 48 instructions per sample to do signal processing right? So > if i process each sample before reading the next sample, will that work in > real time? The code is > > fir.input=( (AdcRegs.ADCRESULT0)>>4); > fir.calc(&fir); > output=fir.output; > > fir.input=( (AdcRegs.ADCRESULT1)>>4); > fir.calc(&fir); > output=fir.output; > > fir.input=( (AdcRegs.ADCRESULT2)>>4); > fir.calc(&fir); > output=fir.output; > ......etc for all other result registers. > > Any help is highly appreciated. Thanks. > > Vik
I hope you have built your executable so this code, and the calculation subroutine, are moved to internal RAM and executed from there. The real question is how long your FIR calculation function takes. See my reply in today's thread "flash and external ram timing on TI 2812" as to how to use one of the 3 general purpose timers to get exactly cycle counts for code execution on the 2812. -- Jack Klein Home: http://JK-Technology.Com FAQs for comp.lang.c http://c-faq.com/ comp.lang.c++ http://www.parashift.com/c++-faq-lite/ alt.comp.lang.learn.c-c++ http://www.contrib.andrew.cmu.edu/~ajo/docs/FAQ-acllc.html