Unable to start?
Check if the battery is not installed or the battery installation polarity is wrong or the battery is dead. Remove the battery and reinstall or replace the same type of battery and pay attention to the correct polarity of the battery.
After the boot or during the operation, the crash and pressing a single button have no effect?
Whether the battery is ectopic (the machine has experienced a fall during use), check whether the calculator mode is wrong, whether the memory is cleared, remove the battery and reinstall and note
Polarity placement of the battery
Correct, clear the machine's memory and initialize the calculation mode (operate in the order of operation shown in Table 1 below).
Show missing strokes?
Check if the machine has been damaged. If you put the machine on the desktop and gently tap the desktop level, turn it back on.
Check if the calculator mode is selected incorrectly, whether the memory is cleared, the machine's memory is cleared, and the calculator mode is initialized (operating in the order of operation shown in Table 1 below).