ADS1x9x EVM code

HECTOR

Other Parts Discussed in Thread: ADS1291, ADS1292ECG-FE

Hello

I am working with ADS1291 and trying to modify the code in the EVM to meet my requirments ;

In the code ADS1x9x_ECG_Processing.c there are 3 filters ; low pass; 50_hz notch, 60 hz notch ;

As I know the notch filter must be an IIR , but as I see it is FIR in the example ; so how could you generate the Coeff. ?

Regards

Hector

over 11 years ago

0 HECTOR over 11 years ago

Intellectual 865 points

Solved

Thanks

0 Don Dapkus over 11 years ago in reply to HECTOR

TI__Guru**** 189399 points

Hi, Hector,

Great! Can you share with the community how you solved it?

BTW, this is a Precision converter, so I'm going to move it to that forum.

-d2

0 Tom Hendrick over 11 years ago in reply to Don Dapkus

TI__Guru**** 168605 points

Thanks Don!

Hi Hector!

Please do let us know what you you did to resolve your issue.

0 HECTOR over 11 years ago in reply to Tom Hendrick

Intellectual 865 points

Hello

The Notch filter must be a IIR filter but you still can design a FIR STOP BAND FILTER ; for example NOTCH _50Hz you can design a high order FIR stop vand filter of frequencies 47Hz-52HZ hamming filter that might do the job too ; that what is implemented in the code ;

Right now I am working on it ; I still could not find the proper filter to delete the DC offset voltage which is not fix from reading to other; the readings are great enough but the DC offset makes the analysis difficult,

Regards

Hector

0 Webb Yang over 10 years ago in reply to HECTOR

Intellectual 260 points

Hello,

I'm using ADS1292ECG-FE and also have a question about the filter setting.

I found that in Live ECG mode when using the 150 BW setting, the HP seemed to be still around 0.5 Hz so the ST segment is distorted.

Is it possible to change the FIR filter coefficients to lower the HP to 0.05 Hz?

Thank you.

Best regards,

Webb

0 Greg Hupp over 10 years ago in reply to Webb Yang

TI__Mastermind 23235 points

Mr Yang -

All of the filtering done for the LIVE ECG mode is done through post-processing the data in the firmware/software; it is not done within the ADC itself. As such, you can change the filter values for your application, but this must be accomplished by changing the software/firmware. The source code is available and is provided "as-is" if you wish to modify the settings for your applications.

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ADS1x9x EVM code