Function Introduction：
1. PIN (Personal Identification Number1) : It is the personal identification code of the SIM card.If not modified by the user, the original
password set by the carrier is 1234 or 0000.If the PIN is enabled, it will require to enter a 4-digit PIN each power-on. The PIN code can be
modified to protect SIM card from being used by others.It should be noted that if input the wrong PIN code three times, the phone will
automatically lock the card and prompt to input the PUK code to unlock it. Therefore, if modify the PIN code without authorization, be sure to remember.
2. PIN2 (Personal Identification Number2) code is in a particular function (such as setting fixed number, set up a call, etc.) have to enter
a personal identification number. Pin2 code is provided by the supplier of the Sim card to another password, used to limit dial-up function
such as a pin, it is mainly used for eliminating combined billing currency don't call cost data, setting and calculation unit, cost limit function, limit dial-up .
3. PUK code (PUK1) : Composed of eight digits, which cannot be changed by the user.When the phone PIN is locked and prompted to input PUK code,
there are only 10 opportunities to input the PUK code. If 10 times are incorrectly input, the SIM card will be permanently locked, that is, scrapped.Part of
the PUK code with the SIM card is the user at the time of purchase with the card attached, while others need to network operators claim if PIN is locked and
don't know the PUK code, don't literally input, at this time should call a SIM card operator's service hotline, after the user data to check, can obtain the PUK code, unlock the phone.
4. PUK Code (PUK2) : PUK2 unlocks PIN2 codes, which are used to unlock services and functions.There are several services: call billing for call charges to zero;
Cost limitation;Price and rate;Fixed dial.To use these features, it is suggested to type in PIN2 code, and if type it wrong three times, it's locked.Typing PUK2 incorrectly
10 times in a row will lock out the functionality of the service it can open, but it will not affect other functionality.