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SigmaStudio gave 'reserved' value for Register bit field...

Question asked by robsoles on Feb 24, 2016
Latest reply on Mar 10, 2016 by robsoles

Version 3.11 Build 2. Rev 1396.

 

Added ADAU1372.dll to C:\Program Files\Analog Devices\SigmaStudio 3.11\. Started new project, dragged ADAU1372 device into workspace, made many changes under various tabs of "IC 1 - ADAU1372 Register Control", including under "Signal Routing" for "Output Select" "DAC 1": "Disabled". "DAC 0": "Input ASRC 0"

 

After hitting "Link Compile Download" and "Export System Files" I examined the contents of the "test_IC_1_REG.h" file and found it seeming to (at least prepare to) load value 0x1C to register (0x11) "DAC_Source_0_1" which seems to go against this giving the bits [7:4] in that register a 'reserved' value - I have always observed 'reserved' values as being a 'no-no' in this sort of thing.

 

On looking closer at the datasheet ( http://www.analog.com/media/en/technical-documentation/data-sheets/ADAU1372.pdf ), page 47, with regard to this register it seems worse when the reset value is defined as 0x10 in one place and then re-defined as 0x1 in another; further, between those two definitions appears similar;

7  6  5  4  3  2  1  0

[0][0][0][1][0][0][0][0]

 

which matches the first definition of the reset value but also happens to have one of the reserved values from the list in "Table 31" regarding "DAC_SOURCE1" using bits [7:4] - come to think of it, both these reset values put reserved values into both fields of this register, [0000] & [0001] are both listed as reserved there

 

 

What with DAC 1 disabled in every other regard I probably do not need to bother setting this source as disabled but, as SigmaStudio allowed me to when I checked this setting, what is actually valid here - is SigmaStudio 'right' that this is the 'disabled' value for that field or is my interpretation of the datasheet right that it is not possible to select other than 1 of the 2 input ASRC streams or is the third option I can think of correct?

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