"123456789*0#"
"3491672850*#"
"1234" - Used to behave differently, it would format flash completely.
It was changed for various reasons and now essential cleans up flash
and goes out and ask for the exact same load it had before. So if you
were running 6.0(2)SR1 it would go and try and reload 6.0(2)SR1.
"349" - Essentially replaces the old functionality of 1234. This
sequence does format flash and causes the phone to come up and ask for
Term70.default.loads. So you have to follow the rules for
this and make sure you are on a DHCP enabled network, have the right TFTP server set
in Option 150 and most importantly that you have a valid
Term70.default.loads and matching application files on that
TFTP server.
***特别标注： 第二种方法不要轻易推荐给客户使用，可能直接损坏硬件****
