It seems that there is a lot of duplication of the text on the Diiv Word Wall, and some of the glyphs are upside down. The words on the Black Books flow in various directions as well, so it is hard to translate them, even if we knew what language it is.
What I do know is that it isn't the Magic Script Langauge (Mage Script) of the Oghma Infinium, Shalidor's Insights, and the Master Illusion Texts, neither is it the Elder Alphabet, as seen on the Elder Scrolls themselves. It appears to be a completely different language, one that hasn't been seen in the Elder Scrolls series before.
Is there a translation of the moving words on the Black Books and the Diiv Word Wall?