These are great ideas. I'm already processing HSERIN interrupts using both ASM and PBP (at different times).
The project (as you would guess) is quite complicated. It does SNMP, telnet ,SSH and RS-232 protocols simultaneously. In some cases the RS-232 port must be connected directly to the telnet port of the network device (a Lantronix MatchPort AR) A whole lot of switching goes on in both hardware and firmware.

It still amazes me that it all works at all. But I'm need a bit more functinality.

Thanks.