Change Sampling Frequency of AD9144 (FMCDAQ2)

Hi,

I am trying to set the sampling frequency of AD9144 to 2GHz. The default is 1GHz when the board is loaded with the provided Linux image.

This is the sequence that I am using:

1. I navigate to the devices directory using cd /sys/bus/iio/devices/

2. ls -l lists the available devices and I can see that AD9144 is named iio:device4

3. Executing cd iio:device4 takes me inside the device directory for AD9144. I execute ls -l to check the available properties for the device. Screenshot of the terminal outputs is given below.

4. cat out_voltage_sampling_frequency gives the present sampling frequency (1 GSPS) of AD9144.

5. I enter the command echo 2000000000 > out_voltage_sampling_frequency to change it to 2 GSPS. But nothing happens. Sampling frequency remains 1 GSPS. I try setting it to 2.8 GSPS since it is the maximum supported by AD9144 but do not see any result.

6. However, trying to change to a lower sampling rate gives the desired result.

I am trying to generate 400MHz gaussian and ricker waves using a higher sampling rate.

I am using SD Card image version 2019_R1. Image filename was 2019_R1-2020_06_22.img.xz, downloaded from https://wiki.analog.com/resources/tools-software/linux-software/zynq_images

Can anyone please help?

- Nairit