YAY! Successfully upgraded my > 10 years old HP-12C's firmware to the new 2025 version which now allows to dump and restore the calculator’s memory via cable to/from my Mac. 😊 #calculator #hpcalculator #hp12c #firmware #hewlettpackard – To see your HP-12C’s firmware version: When the calc is off hold g & ENTER and press ON. Then press 2 to see the checksum, press any key to see the date, again any key to see a copyright notice, again a key to return to the 1.L 2.C 3.H menu. Press ON to exit. 😉