[comp.sys.handhelds] 4 Level Stack Emulator for the HP-48

fin@norge.unet.umn.edu (Craig A. Finseth) (03/28/90)

Here is a partial emulator for a "traditional HP" 4-level stack
machine.  I only did the operations that I thought worthwhile (but I
did do % !).
------------------------------------------------------------
Written by: Craig Finseth, University of Minnesota
From: 24 Mar 1990
What: 4-Level Stack Emulator (

R4KEYS	This contains the key definitions list for use in USER mode.
R4INIT	Saves the value in the Last X register.
R4FINI	Cleans up the stack, duplicating the 4th item, if present.
R4LAST	The Last X register.

Keys Affected:

	key			does

	/> SWAP			Roll Down
	SQRT			saves LASTX
	^			saves LASTX
	INV			saves LASTX
	/> DEL			% properly
	/			saves LASTX
	x			saves LASTX
	/> 2 (Last Arg)	recall LASTX
	-			saves LASTX
	+			saves LASTX

Checksum: #14d
Size: 528
------------------------------------------------------------
%%HP: T(3)A(D)F(.);
DIR
  R4KEYS { S
    \<< 4 ROLL
    \>> 36.3
    \<< R4INIT \v/
    \>> 44.1
    \<< R4INIT ^
R4FINI
    \>> 45.1
    \<< R4INIT INV
    \>> 46.1
    \<< R4INIT OVER %
    \>> 54.3
    \<< R4INIT /
R4FINI
    \>> 65.1
    \<< R4INIT *
R4FINI
    \>> 75.1
    \<< 'R4LASTX' RCL
    \>> 83.3
    \<< R4INIT -
R4FINI
    \>> 85.1
    \<< R4INIT +
R4FINI
    \>> 95.1 }
  R4INIT
    \<< DUP 'R4LASTX'
STO
    \>>
  R4FINI
    \<<
      IF DEPTH 3 \>=
      THEN 3 ROLL
DUP 4 ROLLD 4 ROLLD
      END
    \>>
  R4LASTX 7
END