Sorry to post a reply to my own posting but I have an update to my situation.
I managed to find copies of the ROMMON and IOS software on the Net but I'm having trouble installing them. The ROMMON update went fine and the router restarted to show the new monitor version. When I try to install the IOS I get the following error:
rommon 25 > tftpdnld -u
...
Receiving c820-sy6-mz.124-17.bin from 192.168.0.2 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
...
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
File reception completed.
Copying file c820-sy6-mz.124-17.bin to flash.
Invalid rommon image, aborting download.
rommon 26 >
I have checked meminfo and I have 32m of memory and 128k of nvram. Does anyone know what is going on here please?
Thanks, Steve