28S 'UNDO'

All of the sudden, since just the other day, when I activate the 'UNDO' function on my 28S, it returns the message 'UNDO Disabled'. Did I inadvertantly trip a flag?? How do I re-set it?? Any help is appreciated. I got the thing back in college, and still use it quite a bit, but this is putting quite a crimp in my processes :-(



Yes, I believe that there is an option to turn off the UNDO, in order to speed the machine up and save memory when doing very large operations. Unfortunately, I'm at work, and my manuals are at home.

Try looking in a configuration menu, like MODES or something, and look for an "UNDO" button. My guess is that when you press it, a dot will appear before the word UNDO, and UNDO will be re-enabled. I'm sure that there is also a flag associated with this setting, and I presume that is how you accidentally changed it.

I'll try to remember to look when I go home for lunch, and respond if no one else does.



That did it. Thank you. Sometimes I feel like a complete idiot...and then there are the times when I'm sure of it


Just a hunch: did you run any software before UNDO became disable? Half of the flags of the 28S is used by the system (upper, if I am not wrong). Check for it. Maybe you will find a CF with a previous unchecked value.

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