Philip,

First,

"A) At a 14400 bit rate (8,N,1) and assuming a streaming mode of operation, bytes are arriving ever 694 us"

Is this right? Don't you divide one by 14400 to get .0000694 or 69.4 uS?
Second,
I originally had a AT29C512 (sector written) but abandoned that for the AT28C256 in hopes that it would program like writing to SRAM. Since I'm downloading intel hex format, I had trouble where the bytes were not in sequence due to different org statements in the downloaded program.
This has been an attempt to modify a monitor program to download to eeprom instead of sram, so I'm not sure how much iram I can allow for buffer space.

I've also downloaded a c program from Atmel (flash.c) for the AT29C512 but was unable to compile it as written with my tools. I gave up on that.

Maybe I should just go back to the "burn and learn" and swapping disks from computer to programming station routine or get more sram.

Jon