My adc_capture function returns the same values, regardless which frequency I choose. I am using a FMCOMMS3 board and an Artiz-7 board without any DDR memory, so I replaced the DDR Controller with a BRAM Controller and block memory generator. I don't have the data or instruction cache on my Microblaze core enabled, so the only things connected to the BRAM controller are the ADC and DAC DMAs, as shown below.
In the SDK, the address map for Microblaze doesn't include the BRAM controller address, since it's not connected to Microblaze and the address doesn't appear in xparameters.h. When I manually put in the BRAM address, I repeatedly get the same values. I didn't expect that to work, but what do I need to do to get the BRAM integrated with the ADC and DAC DMAs? Do I have to connect the data and instruction caches? Is there another way to receive samples?