[WP 34S] Enhanced Y register display: fractions, bugfixes etc.

[Paul Dale]

And I did program the flag only prime number sieve

I really didn't want to use numeric flags for special purposes -- I could have lived with less than 100 numeric flags. The 100 numeric flags use twelve and a half bytes of RAM -- one and a half registers -- so the memory used isn't great but still precious.

On the 34S, almost all the mode settings use internal flags rather than user flags & this was intentional. The few settings that do use the user flags are alpha flags not numeric ones. Even here, the flags used (originally) were B, C & D for overflow (big), carry and dangerous -- integer mode required the first two and the third was to improve the user experience without stopping numerical mathematics freaks from doing what they wanted. We did toy with separating these out for a while even though it would introduce a large number of extra commands to set, test and reset them.

It is likely obvious by now that I detest mysterious numeric flags controlling a device. What shall flag #88 do? Oh yes, that means that odd numbers are rounded up to even except on Tuesdays when even numbers are decremented to odd before 6pm but not after. Does anyone remember Fizzbin?


- Pauli