H->HMS conversion HP-15C vs. HP42S vs HP67

[Werner]

A better HMS formula, courtesy of John H. Meyers in comp.sys.hp48, long ago:

H.MS=H.-FP(H.)*0.4-FP((H.-FP(H.)*0.4)*100)*0.004

or

T := H.- FP(H.)*0.4 ;
H.MS := T - FP(T*100)*0.004 ;

translated into RPN that would be

ENTER
FRC
.4
x
-
1E4
%
FRC
4E-3
x
-

At least, it returns 9.59599999999 for 9.99999999999 ..

There's an equivalent HR formula:

H.=H.MS+FP(H.MS*100)/150+FP(H.MS+FP(H.MS*100)/150)/1.5

or

T := H.MS + FP(H.MS*100)/150;
H. := T + FP(T)/1.5;

Cheers, Werner