HP-41C T register duplication disabling

[Didier Lachieze]

(02-21-2020 02:28 PM)Dave Britten Wrote:  Here's an interesting challenge - one I'm not sure I have a good solution for yet: what's the fewest number of steps needed to guarantee that the value in T is different from the value in Z, while preserving the contents of X, Y, Z, and L?

Here is a program for the HP 41 /42S that should meet this challenge. With 15 steps it’s not very short and I’m looking to the RPN experts on this forum for better solutions.

Code:

00 { 28-Byte Prgm }
01▸LBL "T<>Z"
02 X<> ST Z
03 STO ST T
04 SF 25
05 X=0?
06 CLX
07 X≠0?
08 GTO 01
09 CLX
10 1
11▸LBL 01
12 +/-
13 X<> ST T
14 X<> ST Z
15 END