Sunday, August 28, 2022

HP and Swiss Micros 41C and 42S Series: Stack Storage Operations

HP and Swiss Micros 41C and 42S Series: Stack Storage Operations


Introduction  


The HP 41C and HP 42S families, including the Swiss Micros DM41, DM42, Free42, and Plus42, includes the ability to execute storage arithmetic on any of the four* stack levels X, Y, Z, and T.  


The storage arithmetic operator takes whatever value is in the X stack and applies it to any stack level.  If we enter a number before the stack arithmetic operation, the stack lifts first, then executes the stack arithmetic operation.   See the examples section for illustrations.  


*Some calculators allow for a bigger number of stack levels, like 8.  



Examples



Example 1:  


Keystrokes:  3 [ ENTER ] [ ENTER ] 1 [ ENTER ]

Stack:

T:  3

Z:  3

Y:  1

X:  1


Keystrokes:  41:  [ STO ] [ + ] [ . ] (Y)    42:  [ STO ] [ + ] [ . ]  (ST Y)

Stack:

T:  3

Z:  3

Y:  2

X:  1


Keystrokes:  3 

Stack:

T:  3

Z:  2

Y:  1

X:  3_



Keystrokes:   41:  [ STO ] [ + ] [ . ] (Y)    42:  [ STO ] [ + ] [ . ]  (ST Y)

Stack:

T:  3

Z:  2

Y:  4

X:  3



Example 2:  


Keystrokes:  3 [ ENTER ] [ ENTER ] 1 [ ENTER ]

Stack:

T:  3

Z:  3

Y:  1

X:  1


Keystrokes:  41:  [ STO ] [ + ] [ . ] (Z)    42:  [ STO ] [ + ] [ . ]  (ST Z)

Stack:

T:  3

Z:  4

Y:  1

X:  1


Keystrokes:  3 

Stack:

T:  4

Z:  1

Y:  1

X:  3_



Keystrokes:   41:  [ STO ] [ + ] [ . ] (Z)    42:  [ STO ] [ + ] [ . ]  (ST Z)

Stack:

T:  4

Z:  4

Y:  1

X:  3



Note:  Casio fx-991EX Week - September 5, 2022 to September 9, 2022 


Eddie 


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