AD9222 SPI Configuration

Hi,

I'm using an AD9222, and my goal is to program each on-chip ADC in order to test my connection between the AD9222 and my FPGA. So for each ADC I've to set the "Output Test Mode" register.

I read in the AN877 that : During a write process, more than one device may be written at a time by setting multiple bits in these registers high that correspond to the ADC channels to be written. (page 9).

My problem is that I'm unable to find any information on the sequence I've to send (via SPI) to the AD9222 to program the 8 "Output Test Mode" registers after indexing (reg. 0x04 = x0F & reg. 0x05 = x0F) all my registers at once.

Cordially,

G.Blanchard.

  • 0
    •  Analog Employees 
    on Mar 19, 2014 5:08 AM

    Dear Mr. Blanchard,

    I sincerely apologize for the lateness of this reply.

    Register 0x04 = 0x0F and Register 0x05 = 0x0F specify that all eight channels are enabled for actions from subsequent local SPI instructions. The output test modes are invoked using Register 0x0D. The various available output test modes are listed in Table 16 of the datasheet, in the description line for Register 0x0D.

    For example, if you wanted to put the AD9222 into the test mode that outputs a checkerboard on all channels, you would do the following:

    Register 0x04 = 0x0F (Channels E - H activated for next action, this is default so this is not needed unless the value was changed from the default)

    Register 0x05 = 0x0F (Channels A - D activated for next action, this is default so this is not needed unless the value was changed from the default)

    Register 0x0D = 0x04 (selects output test mode with Checkerboard pattern, for channels previously activated for register instructions, in this case all eight channels)

    Register 0xFF = 0x01 (transfer bit invokes previous SPI instructions. I'm not sure this is needed in this case, but it does not hurt to do this.)

    Please let me know if you have any questions regarding this. If the above makes sense, please give it a try and let me know if this works.

    Again, I'm very sorry about the late reply.

    Please take care,

    Doug

  • 0
    •  Analog Employees 
    on Aug 2, 2018 2:32 PM
    This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin