Enter into Factory Mode: *#987#
Restore Factory Settings: *#987*99#
Check Software Version: *#900# OR *#800#
Default User Codes: 1122, 3344, 1234, 5678
Change LCD Contrast: *#369#
To Enable COM Port: *#110*01# -> Device -> Set UART -> PS Config -> UART1/115200
Codes to Change Screen...