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ADS1256EVM-PDK: About long-term log acquisition using ADCPro

Genius 3215 points

Replies: 1

Views: 71

Part Number: ADS1256EVM-PDK

Hi Team,

I have three questions.

(1) Is it possible to get 7 hours AD value log using ADCPro?

  My customers are thinking of putting an evaluation board in a thermostatic chamber to check temperature drift.

  However, when I try to execute it by actually pressing the Continuous button, an error occurs on the PC screen.

  I would like to know what procedure should be taken for 7 hours.

(2) Is it possible to output logs in one file format?

  When my customer checks Auto and presses the Continuous button, new txt files are created continuously.

  My customer wants to get a long log in one file.

(3) How is input switching switched when multiple analog values ​​are converted to digital values?

  In this case, is the sampling period fixed for multiple inputs?

I look forward to your kind support.

Best Regards

Kenji

  • Hi Kenji,

    Would it be possible to share a screenshot of the error message? Is the customer running into this error or is it only on your PC that you are seeing this issue? Let me know if you need additional support on this issue!

    Regarding your specific questions...

    1. Only at very slow data rates can you capture true continuous data for long periods...ADCPro has a limited block size of about 1M samples. However, you can capture blocks of data into multiple files, but there will be gaps in the time domain data, between one block of data to the next. If you're measuring a DC signal, then perhaps this is okay for looking changes in offset.

      Do be aware that the EVM was not designed yo be operated at extreme temperatures. However, from 0-80 C or so it is probably okay... Many of the components on the EVM will not operate across the same temperature range of the ADS1256. Do take care to avoid condensation at cold temperatures possibly resulting in permanent damage to the EVM. 

       
    2. Unfortunately, ADCPro does not concatenate data into an existing file. You'll have to post-process the data files after data collection to get them into a single file format. Files formatting should be consistent though, so perhaps it wouldn't be too difficult to write a script that combines these files into a single file, removing any unnecessary header data from each file.

       
    3. In ADCPro, the UI will allow you to select a single channel and then capture data from that channel. Unfortunately, our software does not perform any channel sequencing, even though the ADS1256 could support this behavior in a real application.

      In the customer's own written software, they could reprogram the ADC's MUX after each conversion to cycle through multiple ADC channels. This process is shown in Figure 19 of the ADS1256 datasheet and the maximum data rate when multiplexing is shown in Table 14.

    Best regards,
    Chris Hall
    Applications Engineer | Precision ADCs


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