Get Data from Storage File
txt, len = e:get(max)
Pull up to max bytes from the Storage File.
This call may not return a whole record, but just up to the next flash page boundary.
You may need to call this function twice, or more, to pull a complete record.
This function can return a length of zero, even when there is more data to read.
Use emulation.adv to determine the end of frozen data.