bluno nano, It doesn't work HID keyboard.

Hello.

I want to make nano keyboard for android or i-phone.
this keyboard only has page down and page up.

My Bluno v 1.3 is working good width android application.
But I can't success HID keyboard mode.

I am tested follow sequence:

1) +++ enter at mode
2) AT+SETTING=DEFAULT
3) AT+ROLE=ROLE_PERIPHERAL
4) AT+FSM=FSM_HID_USB_COM_BLE_AT
6) AT+MIN_INTERVAL=10
7) AT+MAX_INTERVAL=10
8) AT+KEY=4

all command response is OK.
But android did not any operation.

What is wrong for me?
Did you have any sample code for hid keyboard?

Thanks for all.