|Re: HP 10B continuous memory|
Message #4 Posted by Mike Morrow on 31 May 2011, 1:25 p.m.,
in response to message #1 by hpnut
What you see is normal. Stack (or rather, Display) contents are not preserved on the 10B and 20S, as Bart states. Registers and program memory (on the 20S) are preserved. (I just turned on my 10B and 20S for the first time in several years, they still have what I left in them from that time.)
Store something in Register 3, turn the 10B OFF, then back ON. If Register 3 still has what you stored, its CM is working.
FWIW, I think the HP-41C and the Voyagers were the first HPs to preserve everything including the stack. I don't recall that *any* LED HP calculators with CM preserved the stack. I know that the HP-19C, -29C, and -34C don't, so I suspect the 25C that you cited doesn't either (but I don't own one to test). Perhaps the LCD 10B and 20S Pioneers don't preserve the display (and internal stack) the way RPN Pioneers preserve their stack is due to them being non-RPN algebraic models. The HP 10bii doesn't preserve the display either. What about the new HP 10bii+? The HP 30b in algebraic mode *does* preserve the display.
Certainly some other HP calcs contemporary to the 25C do not have any CM. Stuff like the HP-67, -97, etc.
Edited: 31 May 2011, 1:46 p.m. after one or more responses were posted