ADAS3022 CFG Readback

ADAS3022 CFG Readback question. On page 33 of the datasheet, there is as CFG Readback section. Will that feature give me back the CFG data for the channel that was read out ? For example, at the EOC, CFG for channel (n + 2) is sent on DIN and data for channel n is sent back on SDO.

If CFG (n+2) is then sent again on DIN (to create SCKs) without toogling CNV, is CFG for channel n then sent on SDO ? Therefore one can correlate the data with the value in the CFG that was sent back ? Or does it send back the CFG (n + 2) that was just sent on DIN ?



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    •  Analog Employees 
    on Feb 12, 2014 3:54 AM


    we are looking into this and we'll get back to you soon.



  • Thx for looking into this. Also there are no timing diagram(s) in the data sheet that shows how this 'CFG readback' works. The referenced Figure 69 that does apply to the CFG Readback feature.

    We plan to use the ADAS3022 with 8 inputs, so there will be 8 channel to control with your pipe-line scheme. It would be ideal if the CFG Readback feature really worked as it seems to be describing in the CFG Readback section.

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    •  Analog Employees 
    on Feb 13, 2014 2:39 AM

    I think you have aksed the same question through our customer support.

    As you have noted, the conversion result and the CFG register are updated at the EOC. As shown in figure 4 and 38 (note 3), a total of 16 sck falling edges is required for a conversion result and an additional 16 edges are required to read back the CFG result associated with the current conversion. The CFG readback feature is also specifically explained in figure 69 and on page 33.

    You have to keep in mind that if you want to use the combination of single-ended and differential input modes on the fly, you cannot use the sequencer mode since you have to rewrite the CFG word and wait two-deep delay before the CFG settings takes effect each time you want to switch it from single-ended to differential input mode.