John,

First:
---"A) At a 14400 bit rate (8,N,1) ... 694 us"

Is this right? Don't you divide one by 14400 to get .0000694 or 69.4 uS?
--- yes that is the bit rate but it takes 10 bits to assemble a byte if it's 8,N,1. 8 data 1 start,1 stop.


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.

--- If you are un-wrapping intel hex the buffers are filling more than twice as slowly due to the ascii representation of a byte.
--- Ok this is a downloader. How does the Host system download this data or are you using a terminal program. If it's a terminal program such as Procomm, remember you can control the "line rate" that is, a delay after CR/LF that is programmable. Every new "org" will emit a line (cr/lf term'd). The delay could be made 10ms if desired.


Third:

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.

--- How much RAM can you spare IRAM/XRAM?

regards,
p