*The Museum of HP Calculators*

This program is Copyright © 1999 by Michael Harwood and Paul Picot and may be freely used by permission.

This program is supplied without representation or warranty of any kind. Michael Harwood, Paul Picot, and The Museum of HP Calculators therefore assume no responsibility and shall have no liability, consequential or otherwise, of any kind arising from the use of this program material or any part thereof.

The most frequent base changes are between the decimal,
binary, and hexadecimal systems. Hexadecimal <-> binary conversions
are trivial, so all that is needed is a program to convert decimal to hexadecimal
and vice versa.

There are actually two programs: (i) "H^D" (hex to decimal) and (ii) "D^H"
(decimal to hex).

* I assign them to the "P^R" and "R^P" keys.*

**These programs are short and use no flags nor any storage registers.**

The decimal number is entered in the X-register. The hexadecimal number must
be entered in the Alpha register. The results of the conversion are
also displayed in these two registers.

1) Convert 42 to hexadecimal

2) Then convert C5 to decimal

KEYSTROKES DISPLAY COMMENTS42 42 XEQ "D^H" 2A The answer! ALPHA 2A (last thing in Alpha register) C5 C5 ALPHA 0 XEQ "H^D" 197 The answer!

Therefore 42_{D} = 2A_{H} and C5_{H} =
197_{D}

You can only enter the digits 0-9 and A-F for the HEX to DEC conversion. If you enter an invalid character, the computer will sound tone 0 and display some number. (The only invalid characters that are not detected are : ; < = > ? and @ . This is because the error checking would just make the program longer.)

How to get this Program to your Calculator (via
HP-IL, disk, wand, and fingers)

Download Binary (.raw) program for disk or PC HP-IL Card download.
(This version was combined into a single program by Pierre Hardy by
replacing the END on line 31 with RTN and concatenating.)

`01LBL"H^D"
hexadecimal to decimal (the number to convert must`

`02
0
already be in the Alpha`

`03LBL
01
register)`

`04 ATOX`

`05 X=0?`

`06 GTO 02`

`07 70`

`08 X<Y?`

`09 GTO 04 invalid
character`

`10 RDN`

`11 57`

`12 -`

`13 X<=0?`

`14 GTO 03`

`15 7`

`16 -`

`17LBL 03`

`18 9`

`19 +`

`20 X<0?`

`21 GTO
04 invalid
character`

`22 X<>Y`

`23 16`

`24 *`

`25 +`

`26 GTO 01`

`27LBL 04`

`28 TONE 0`

`29LBL 02`

`30 RDN (Bug fix supplied by
Pierre Hardy`)

`31 END`

`01LBL"D^H"
decimal to hexadecimal (number to convert is in X-reg)`

`02 CLA`

`03LBL 01`

`04 ENTER^`

`05 ENTER^`

`06 16`

`07 ST /Z`

`08 MOD`

`09 9`

`10 -`

`11 X<=0?`

`12 GTO 02`

`13 7`

`14 +`

`15LBL 02`

`16 57`

`17 +`

`18 XTOA`

`19 -1`

`20 AROT`

`21 RDN`

`22 RDN`

`23 INT`

`24 X!=0?`

`25 GTO 01`

`26 AVIEW`

`27 END`

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