Sending pulse to each channel

johnwastaken · Post by **johnwastaken** » Mon May 30, 2011 7:17 pm

I have created a converter to import BioSemi data into ERPLab. I would like to test the converter to ensure each channel is importing the data as it should. Is there a way to create artificial data on the BioSemi intuitive to testing my software? i.e. - is there a way to send a pulse to each individual channel in the array to ensure that the import process is working correctly?

Cheers,
John

Post by **Coen** » Tue May 31, 2011 4:25 pm

The most simple method is probably to make a recording with the electrodes in salt water, and to lift the electrodes from the water one by one.

Best regards, Coen (BioSemi)

johnwastaken · Post by **johnwastaken** » Tue Jul 12, 2011 9:44 pm

Thanks Coen,

There is a further reason why a specific cal-pulse needs to be sent. When importing the data, the software requires you set a gain and a resolution. I need a way to calibrate so I know that the actual amplitude being measured is the same as the amplitude of the data I am analysing. Any ideas?

Post by **Coen** » Wed Jul 13, 2011 12:03 pm

The software should calculate the scaling from the values give in the BDF header, see http://www.biosemi.com/faq/file_format.htm. This leads to LSB = 31.25 nV for the EEG channels. Check your software by making a BDF file with a two bucket test and a calibrated signal generator.

Best regards, Coen (BioSemi)