01-28-2020 11:56 AM
I recently acquired a ZCU 111 board and I am planning to use it with some RF applications. In order to do that, I need to establish communication with the ADC/DAC in this board. I have trouble in figuring out clocking in XMC 500 board. It'd be a great help if I could have a ADC-DAC loop back design with a wiring diagram on the board.
Can someone point me to a starting point.
01-28-2020 09:10 PM
I would reccomonded you to refer board user guide first which have detailed information on which ADC/DAC channle connected which connector on XM500 Daughter card.
i.e Appendix D (HW-FMC-XM500 )
once it is figured out , you can create a simple ADC-DAC (internal loopback) or DAC-ADC external loopback.
For the required clocking i.e configuring the on board RFPLLs , you can use SCUI utility provided by xilinx or simple SDK application.
01-29-2020 06:44 PM
Thank you for the kind response.
I am a Linux user and I tried to install SCUI utility. However, the installation fails throwing an error in finding the Vivado installation directory. I pointed the correct Vivado folder, yet the installation does not accept it.
I have used ZCU 1275 board and it has its own clock module to generate the ADC clock. My design works fine in that board. I used a similar design and provided the clock using a Valon frequency synthesizer via differential inputs, as the SCUI utility does not work on my linux machine. This did not work either.
I tried implementing the design you suggested. The user guide suggests to reset the data converter IP and hold it to 0 until the clock stabilizes. I did that by writing an RTL to hold the reset to 0 until I press a button. Then forced the reset to 1, and kept it as 1 unless I press the reset button. However I am unable to generate the DAC clock. I tried using a simple counter to check the dac clock output. But the clock does not start. Do you think I am missing something?
Is there a sample project that I can check? If so it'll be a great help.
01-29-2020 10:55 PM
It sounds like that the reference clock is failed to supplied to DAC.
If you are using external clock source from XM500 daughter board DAC clock input SMA connector instead of on board LMK2594 output, you have to do some rework on ZCU111 board. Because some of the capacitors which are used for ac-coupling the external clock source on ZCU111 are not mounted defaultly. Please take a look on the ZCU111's schematic if you haven't done that.