Service codes "Chinese" models:

Service codes "Chinese" models:

* default user code: 1122, 3344, 1234, 5678
* Engineer mode: *#110*01#
* Factory mode: *#987#
* Enable test mode COM port: *#110*01# -> Device -> Set UART -> PS Config -> UART1/115200
* Restore factory settings: *#987*99#
* LCD contrast: *#369#
* software version: *#800#
* software version: *#900#