The Rev. B Zedboard is 8 years old now - ancient in technology terms - and was fitted with an Engineering Sample (ES) Zynq device that have a long list of errata:
I can sympathize that you may want to be able to reuse one of these older boards with ES Silicon. We as engineers tend to desire efficiency within our lives and try to not waste hardware, if possible. However, my best and most respectful advice is to update to a current-rev board. I know it probably seems silly to throw away an old board, but the cost of a brand new ZedBoard, or perhaps better yet the (less than $200), is far less than the amount of engineering time you will waste on getting any new designs working with an old Rev. B ZedBoard.
Ok, thank you very much.