Hi Ben, Thanks for the link; it's allowed me to make some progress. My 210 has no issues getting to the U-boot prompt and I was able to set the tftp environment variables: ip, netmask, gateway, server ip. Resetting has never been an issue.
I cannot access the Loader Prompt. Rather than getting the message during bootup about "Loading /boot/defaults/loader.conf", mine returns "## No elf image at address 1x00100000" and goes straight back to the u-boot prompt.
Without the Loader Prompt, the procedure described in the link will not work.
But, now that I know I'm dealing with a corrupt, or missing, Loader Prompt, I can refine my searches to hopefully find a solution.
-Jared