ADS1299EEGFE-PDK: what settings should I use to get data from electrodes

Hi Sam, 

Just to confirm, you have the ADS1299 PDK software GUI installed and it loads up successfully? Does the GUI recognize the ADS1299 PDK?

Kind regards,
Nick Z

Hi Nick,

Yea, I have the software installed. I believe the GUI recognizes my board, I say that because if my board is not connect to the PC via USB, then the GUI wont open. I adjust of sample per channel to match the time I want to collect data. for example, for 250 (SPS) Sample per Second I change the number of sample per cahnnel ro 2500 for 10 seconds of data. the issue is my output data is gibberish, and I'm wandering if its a software or hardware setting issue. 

Hi Sam,

I will take your questions from here.

In the GUI's first "About" page, can you read the Firmware version? If yes, and you do not see any Download fail nor Timeout error, then you are in a good start.

Secondly, It's highly recommended to take pictures and note down the default jumpers settings/configuration for future reference and reset.

May I ask what signals and source of the signals are you injecting? Are they Single Ended or Differential? What might be the magnitude?

May I ask are you trying to implement

the Sequential(differential) Montage(ADS1299 datasheet Page 66 Figure 72 or ADS1299EVM user guide page 17 section 4.6.1) or

the Referential(Single Ended) Montage(ADS1299 datasheet Page 67 Figure 73 or ADS1299EVM user guide page 17 section 4.6.2)?

According to ADS1299EEG-FE EEG EVM user guide, page 51 schematic, the EVM is setup for Sequential(differential) Montage.

Please take a look of EVM user guide 4.6.1 and 4.6.2 to configure J6 and/or JP25.

May I ask why you select "Bias positive electrode driver"?

If your inputs are Differential, in the GUI, go to "ADC Register->Channel Registers->Channel Control Registers GUI Panel", for the channel you inject signal, select it to Normal Operation, Normal Electrode, SRB Open(Off), and you will need to adjust the PGA gain from small to large to see if you can observe the signal.

Let's use 1 channel at a time first, and Can you let us know which channel are you using for now? and attach/provide pictures of your "ADC Register->Channel Registers->Channel Control Registers GUI Panel" settings?

Thanks

Hi, to answer your questions:

1) in the "about" tab/page the firmware version is ADS1299 rev1 firmware version 0.0.27. I just confirm there are no download fails or errors.

2) for the hardware configuration, I confirmed the hardware configuration matched the default settings from the data sheet.

3) the source of the signal is from an electrode on my chest/heart, the electrode is connected to to the Pin 28 of J6 connector via a cable with alligator clips (on electrode) and micro grabbers (on pin 28 of J6). this would be single ended signal. I'm not sure what the magnitude of the heat beat would be. 

4) I'm trying to verify my setup to confirm I'm taking real data. eventually I want to keep the same setup, but move the electrode to my forehead. 

5/6) I have a Single ended signal. pin 28 is the positive (signal is being fed to pin 28 J6) and pin26 is shorted to pin 25 (default). in the GUI under "ADC register" tab/page --> channel register, for channel input I select "BIAS Positive electrode driver" to accommodate a single ended signal. based on your comment, it seems I should re take the data with "normal electrode" setting. any other settings I should change before re-taking data? 

Thank you

Hi,

1) sounds correct.

2) Good.

3) Before going to human body, Please refer to datasheet 9.3.1.1.2 and 9.6.1.3 and 9.6.1.6 and user guide 5.3.1 Internal Test Signals Input to do Internal Test Signal first.

It's recommended to make sure the Internal Test signal work properly before going to ECG simulator and human body.

Thanks.

Hi, I have a question on "continues" data gathering. when I set the data rater to 250SPS and Sample/CH to 2500 and press "continues". the data gathering automatically stops around 10 second +/- few seconds, which is expected. however, if I change the Samples/CH to 60,000 (2 min worth of data) the GUI takes much longer that 2 min to automatically stop, (it take longer that 3 min to automatically stop). my question is: 

should I manually stop the data gathering after 2 min by pressing the "continues" button again? 

If I don't manually stop the data gathering let it run till it automatically stop, what window of data was truly gathered? the first 2 min, or the last 2 min? 

Hello, 

In that case is there a newer version of the software that you could recommend? If NOT, are there other board I could purchase that will come with an updated software? 

Thank you,

Hi,

If you set DR = 250 SPS and select 60,000 samples per channel, how many channels did you enable?

60,000 samples per channel by a data rate of 250 samples per second -> 60,000 samples/ 250(samples/sec) = 240 sec needed to acquire/collects the amount of samples you want.

And, if you enable n channels, then it's total of 60,000 * n samples you are collecting and these samples need to be streamed to display on the GUI and in between, there are uController, OS, APIs, processes and GUI software that add delay/latency.

I may suggest if you want to collect a large number of samples, you can increases the Data Rate to higher SPS.

TI does not have newer version of EVM board nor software for this.