Hi All,
I'm using HSDIO 6556 lines for 4-wire SPI communication of digital device whose output is a 16-bit digital output from the ADC. We need to use SPI 4-wire communication to talk to the digital registers in order to acquire the 16-bit digital output from the ADC.
I'm using a bread board to hold the device, and connecting the SPI lines through wires. The power-up of the device are done through wire's using SMU channels.
The problem I'm facing here is, I'm able to read the 16-bit digital output from the ADC using shorter wire length of approx 10 inches long. But the same setup, while trying with wire length of 1 to 1.5 meter long, I'm not able to acquire the raw data from the ADC correctly. There are missing bits in the data.
I'm using Labview2013 for this HSDIO acquisiton and generation. I have tried with the HSDIO properties of "Delayed Data Active Event" in order to compensate for the round trip delay. But still I was not able to acquire the data correctly.
So my question is, Whether the wire length really matters for SPI communication? Is there any limitation on the cable length during HSDIO acquistion and generation? Or whether the HSDIO calibration is limited to particular length only?
Kindly help me in this regard.
Thanks & Regards,
Pramod Kumar