I am using a dual ADC ad9652 which comes with a function of setting the LVDS digital output to a number of fixed test patterns. The test patterns include all ones, all zeros, alternating all ones and all zeros and checkerboard. I have used this test mode function for a single ADC without any question. But with a dual ADC, it appears as if each ADC has its own pattern and so the same pattern would appear twice in a row when the output of two ADCs are interleaved on a single 16bit LVDS bus. For example, after setting the register 0x00D in the register map using SPI to the value of 0111binary, the output becomes
as opposed to an alternating pattern of 0xFFFF and 0x0000.
Is it a correct behaviour?