Thinking about an HP-41CL

[smp]

Thanks very much for your thoughts, guys.

I purchased the SIO cable and the special port cover along with my 41CL, so I'll be ready to go with that. The curious thing for me is that there is no mention of what to do with that interface in the manual (or so it seems to me). There is a description of the internal cable and the connector, but that seems to be all. Is the SIO used very often, or only once in a while? I was hoping that it was something like a backup mechanism to a PC, but it appears that I might still need HP-IL for that?

Thanks,
smp