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AD9102 - Trouble with DDS mode and reading from SRAM??

I have the AD9102 EVboard and I can get all modes to work: constant value, Sawtooth, DDS, and reading from SRAM.  However, on my proto-layout board, I program the Ad9102 SPI directly and I can only get the constant value and Sawtooth mode to work.  The DDS and read from SRAM do not give any output.  I am taking the regval and default sequence from the EVboard software and and programming into AD9102 SPI directly.  So inputting example4 settings gives me the pulsed triangle wave for the sawtooth mode which is working, but the sine wave of example6 is not working.  The registers and SRAM are able to read and write properly. Is this a common problem or am I missing something obvious?  Any help would be appreciated, thanks.

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  • Hi Biao,

    I have tried many times to use 0x1231 and 0x1230, but still having trouble getting AD9102 output to read from SRAM.  I don't get the continuous sine wave like the EVboard, but I care more about reading from SRAM.  So the interesting part today was that I made some patterns to match the SPI reg writes for the EVboard's DAC1 tab and Pattern Config tab.  What I am seeing is the 0x0027 register bits do not stick whenever I send in example2, example5, or my own reg settings for DDS mode off SRAM. Reading back 0x0027 always seems to be 0x0101.  Example4 does work and reads back 0x3212 on 0x0027 reg. 

    Writing DAC1 tab settings first, then Pattern config tab settings second causes 0x0101 to be in 0x0027 reg.  If I do Pattern Config tab settings first, then DAC1 tab settings, then 0x0027 reg goes to 0x3030.  This is telling me that there seems to be a special sequence to get all the reg settings to stick, or that the internal switches for DDS mode are damaged and can't be turned on.  Do you have any common info on AD9102 and whether it needs special SPI sequences?   I attach my SPI address sequence from my scoping the EVboard SPI.

    Dan

    DAC1 tab setting address sequence:

    0x0045

    0x005D

    0x005E

    0x005C

    0x005E

    0x0027

    0x001F

    0x002B

    0x0035

    0x0025

    0x003E

    0x003F

    0x0043

    0x0031

    0x0037

    0x0047

    0x005F

    0x001D

    Pattern Config tab setting sequence:

    0x0029

    0x0028

    0x0044

    0x0060

    0x002C

    0x002D

    0x0020

    0x001D

Reply
  • Hi Biao,

    I have tried many times to use 0x1231 and 0x1230, but still having trouble getting AD9102 output to read from SRAM.  I don't get the continuous sine wave like the EVboard, but I care more about reading from SRAM.  So the interesting part today was that I made some patterns to match the SPI reg writes for the EVboard's DAC1 tab and Pattern Config tab.  What I am seeing is the 0x0027 register bits do not stick whenever I send in example2, example5, or my own reg settings for DDS mode off SRAM. Reading back 0x0027 always seems to be 0x0101.  Example4 does work and reads back 0x3212 on 0x0027 reg. 

    Writing DAC1 tab settings first, then Pattern config tab settings second causes 0x0101 to be in 0x0027 reg.  If I do Pattern Config tab settings first, then DAC1 tab settings, then 0x0027 reg goes to 0x3030.  This is telling me that there seems to be a special sequence to get all the reg settings to stick, or that the internal switches for DDS mode are damaged and can't be turned on.  Do you have any common info on AD9102 and whether it needs special SPI sequences?   I attach my SPI address sequence from my scoping the EVboard SPI.

    Dan

    DAC1 tab setting address sequence:

    0x0045

    0x005D

    0x005E

    0x005C

    0x005E

    0x0027

    0x001F

    0x002B

    0x0035

    0x0025

    0x003E

    0x003F

    0x0043

    0x0031

    0x0037

    0x0047

    0x005F

    0x001D

    Pattern Config tab setting sequence:

    0x0029

    0x0028

    0x0044

    0x0060

    0x002C

    0x002D

    0x0020

    0x001D

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