• Completely rewritten Owner's Manual. The full HP-16C handbook, page by page: every section, every worked example, the stack diagrams, the shift and rotate diagrams, both IEEE format-conversion programs, the Function Summary and a linked Subject Index. Display readouts are typeset exactly as the calculator shows them. • New appendix on the Voyager series: how the 16C compares with the 10C, 11C, 12C and 15C. • Low-battery indicator: the LCD's "*" annunciator now reflects your device's battery, just as it did on the original.

Self-tests are here! This update brings the calculator's built-in diagnostic tests to life, working exactly as on the original hardware: • Self-test — hold × and ON: the ROM runs its full diagnostic and finishes with the famous all-segments display • Keyboard test — hold ÷ and ON, then press every key in sequence • Continuous self-test — hold + and ON for the endless diagnostic loop All three are also available from the Calculator menu on Mac. Under the hood: • More accurate emulation of the display driver hardware, verified against a real calculator • The display now shows the complete set of annunciators, positioned to match the original LCD glass • Improved handling of simultaneous key presses Thanks to the community at the Museum of HP Calculators forum for the sharp observations that led to this update!

You can now switch between period and comma as the decimal separator, just like on the original calculator. Turn off the calculator, press and hold the decimal point key, then tap ON. The radix mark and digit separator will swap instantly. Also fixed: display annunciator labels now match the original HP hardware.