Hey everyone,
I wrote a minimal hardware configuration that blinks all the accessible LEDs and outputs square waves of different frequencies on all 12 of the GPIO outputs on the DF52 board. This might be useful for people to test whether or not their board works after they get it. The vivado project can be built by cloning my github repository (found here
https://github.com/SMB784/SQRL) and using the TCL script build_SQRL.tcl. The github repository also includes instructions on how to program this board using a generic FT232H to USB adapter rather than the usual special Xilinx cable, as well as automatic scripts for uploading the post-implementation SQRL_top.bit & SQRL_top.bin files for programming the FPGA and the flash.
In order to get 3.3V output on DF52 pins 15, 16, 18, and 19, you are required to remove the U11 regulator and short the input and output pins on the U11 pad together, as described earlier in this thread. I have confirmed that this works, and does not negatively affect the board in any way that I have noticed.
I have attached images of the waveform output from pin 3 (3.3V GPIO pin at 12.5 MHz output) and pin 19 (2.5V LVDS pin modified to 3.3V GPIO at 6.1 kHz output ) to this post.
If you need to put together a DF52 cable, I highly recommend getting the specific DF52 cables with the pre-crimped ends (
found here on Mouser) that fit into the DF52 housing (
found here). Cutting the cables in half will allow you to make 2 DF52-to-whatever-you-want cables (in my case, IDC20 connectors).
Hopefully this helps someone else make good use of this board