stack lift and change sign

[walter b]

Read the first 30 pages of Wickes' "41-48 transitions" who basically states that the HP-48 just extends the way the HP-41 calculates, allowing also objects which aren't just plain real numbers. Still don't get why there's such a bohai about "stack lift" - to me the stack maneuvers of the 48 aren't any better, just different.

Let's look how e.g. (1+2)*(4+5) is calculated on an HP-48 as on an HP-42:

1 ENTER 2 + 3 ENTER 4 + *

Code:


HP-48:  Entry line:  1:    2:        HP-42S: X:    Y:    Z:          
1                1                           1                         
ENTER                1                       1      1                  
2                2   1                       2      1                   
+                    3                       3                          
4                4   3                       4      3                 
ENTER                4     3                 4      4      3         
5                5   4     3                 5      4      3         
+                    9     3                 9      3                  
*                   27                      27

On the 42S, ENTER always duplicates - on the 48, ENTER only duplicates if the entry line is empty. Personally, I prefer a function doing the same always (remember you've no chance to follow that weird behavior of ENTER on a single line display).

d:-/