Need help with HP-71 HP-IL Interface Module

[wallyhp71b]

Hello - I would appreciate any help with verifying the working condition of my HP-71 HP-IL Interface Module 82401A.

I'm a long time HP handheld calculator user and just recently got out of storage (30 years) my old HP-71b calculator and accessories, including an original boxed Hp-71 HP-IL Interface Module 82401A. Everything in the box looks brand new. I must have bought this years ago but now don't have any HP-IL device to connect it to.

So how can I check to see if it's working?

The HP-71b works great. It powers on, with new batteries, and when I type VER$, displays "HP71B:1BBBB".

But when I[/size] plug in the 82401A module, the HP-71b does not seem to recognize it, and when I type VER$, still only displays "HP71B:1BBBB"

Also when I type RESET IO or RESTORE IO or try other HPIL commands, the HP-71 beeps and displays "ERR:excess chars".

It's been decades since I've used my HP-71b so I'm very rusty on using it now.

I've tried to do online research to re-educate myself on this but can't find any answers.

Any helpful suggestions that I could try, to verify if the Module is working, would be much appreciated.

Thanks for sharing your knowledge.