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http://www.8051projects.net/forum-t7667-last.html


please post your doubts about

smoothening techniques here]]> Wed, 26 Mar 2008 23:44:24 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html
i am taking u there one by one..

yes we are intro ducing incorrect data... thats why i said it shud not be implemented thru software but mostly thru hardware!!!]]> contact@nospam.com (Ajay Bhargav) Fri, 28 Mar 2008 07:11:25 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html ]]> contact@nospam.com (Ajay Bhargav) Fri, 28 Mar 2008 08:50:22 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html Ajay wrote ...

you must click on thanks button

Done dude......now Amit's turn ]]> contact@nospam.com (Ajay Bhargav) Fri, 28 Mar 2008 10:31:16 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html ]]> contact@nospam.com (Ajay Bhargav) Fri, 28 Mar 2008 11:07:33 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html Is this the thread you mentioned? Good idea! But please do post something soon.. am waiting eagerly. And if possible do include help in assembly and not only C. Will be a huge help for noobs like me ]]> contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 06:48:22 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html http://www.8051projects.net/forum-t7667-last.html

this thread is only to discuss the doubts regarding the above link ]]> contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 10:46:13 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 11:52:07 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html
and yes u cant post there so all doubts will be solved here..


well implementing the sample hold technique can be done thru a micro controller it is easy!!!...

but it is like fooling your client

this is the way to do it..

all you need is to make the changes in the ADC data a little slower!!..

step1 . set interval for sampling.. suppose 1 sec..
step2 set interval to display data.. assume u r making a graph so points per sec suppose 5.
step3. read data @ADC at sampling rate...
step4 .no need to read the next 4 values simply copy the values to the next 4 variables.. repeat step3 and 4.

ex..

sample 1 =0 sample 2 =1 sample 3 =2 sample 4 =3 sample 5=2 sample 6 =1 sample 7 =0

u will get the following representation



*****
***** ____*****
*****_______________*****
*****__________________________*****
012345678901234567890123456789012345


thus you will get a theoritically smooth looking graph but practically it is useless...
therefore sample and hold technique is seldom used in softwares/codes... it is mostly an hardware implementation...
simplest S&H mechanism is the operation of a capacitor..
u can add a capacitor into your input(adc) to get the S&H response.

keep reading as i will be posting more techniques.. ]]> contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 20:53:02 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html ]]> contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 21:10:01 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html ]]> contact@nospam.com (Ajay Bhargav) Thu, 27 Mar 2008 22:09:41 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html
But I have a doubt. By copying the data to then next 4 variables, arent we introducing incorrect data there as there is a possibility the ADC o/p may have changed at that instant.

Also, can this be used as a replacement to the barrel shift algorithm u mentioned earlier?

By using a capacitor before the i/p of ADC will surely help smoothening out the variations! Il try that for sure!!!

Thanks a million!!!]]> contact@nospam.com (Ajay Bhargav) Fri, 28 Mar 2008 05:35:29 -0700 http://www.8051projects.net/forum-t7669.html Re: doubts on smoothening techniques for ADC/DAC data (DSP) http://www.8051projects.net/forum-t7669.html http://www.atmel.com/dyn/resources/prod_documents/doc8003.pdf]]> contact@nospam.com (Ajay Bhargav) Sun, 30 Mar 2008 01:01:14 -0700 http://www.8051projects.net/forum-t7669.html