Thanks for the info. Yes, I was getting messed up with the 'block select' bit - did not realize the 515 was actually 2 x 256, and you have to change this bit to address the rest of the memory.

Question: My data payload is only 36bytes. I have a page size of 64bytes.. How can I both use the [string] to write pages, and not waste space? Or is it possible?

Since my payload is 36bytes, if I write a byte at a time, that will take .36 seconds, which is too long. If I write the page, it is what 5ms?

Thanks,
TG