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

[Thomas Okken]

It doesn't multiply the entire number by 10^12, just the fractional part. But, yes, with a case like that, numerical cancellation will cause the binary round-off to mess up the result. Avoiding that is possible but ugly (I think the 33S does this).

This is why Free42 Decimal exists.

UPDATE: Hadn't read your post carefully enough. Better binary-to-decimal does sound like a good idea. I'll look into it sometime after my vacation...