Forum Post: RE: No signal from the DOUT pin in ADS1299 EEG-FE

Hi Xinling, 

Your SCLK speed is ok. The minimum requirement for eight 24-bit channels + STATUS at 250 SPS is 55 kHz as calculated by Equation 6 on page 26 of the datasheet.

If JP21 = [1-2], /CS is tied to J3 pin 1, not pin 7.

If JP22 = [1-2], your START signal is tied to /CS. Default for JP22 is [2-3] so that START is tied to J3 pin 14.

If JP23 = [1-2], then CLKSEL is tied to GND and you must provide an external clock. 

Please confirm that you are using the correct jumper settings for /CS, START, and CLKSEL.

Thanks and regards,