Stack movement keys as second function on the 34 and 67

[Steve Simpkin]

(02-13-2022 06:46 PM)Matt Agajanian Wrote:  Hi all.

R↓, R↑, and x↔︎y are the essential stack tools. With the exception of the 34 and 67, the other models have them as primary. So, why are they second functions on these models? This has always struck me as peculiar.

Thanks

I suspect it is because these models had so many functions (most keys had 4 functions) that the designers had to carefully choose what functions were most likely to be used and assign them as primary functions.
To clarify, X<>Y is a primary function key on the HP-34C. Also the X<>Y and R(down) are primary function keys on the HP-67 *if*you don’t have a program loaded that uses the D and E labels.
I looked at the HP-34C key layout and I am not sure what I would have personally swapped the R(down) key with to make it a primary function. By the way the R(up) key is shifted on many (all?) of the models that had it.