keychron_qmk_firmware/keyboards/hhkb/rn42/RN42.txt

RN-42 Bluetooth Module Support
==============================
Bluetooth controller board works with HHKB Pro2, JP, Type-S and Type-S JP and it supports both USB and Bluetooth as keyboard output protocol. Bluetooth module Roving Networks/Microchip RN-42 is installed on the board.


RN-42:
http://www.microchip.com/wwwproducts/Devices.aspx?product=RN42


Capabitlities:
- USB keyboard functions
    completely equivarent to USB controller including mouse keys and NKRO.
- Switching between USB and Bluetooth
    You can switch the two connections with BT switch or key combination.
- RN-42 config mode
    You can change power/connection configuration of the module if needed.
- Low battery alert
    Red LED turns on when low voltage.
- RN-42 status indicator
    LED indicates status of Bluetooth connection.
- Pairing
    The module stores up to 8 connections.
- Auto connect
    The module connects the last connected device automatically.
- iOS support
    works as keyboard with iPhone5. No tested completely.
- Android support
    works as keyboard and mouse with Nexus5. No tested completely.
- Mouse keys over BT
    Note that iOS doesn't accept mouse device.


Limitations:
- Short battery life
    Around 12hr with 1000mAh
- No connection switching
    RN-42 auto-connects to the last connected device.
    Some of consumer products can switch between devices, for example Logitech K480.
        http://www.logitech.com/en-us/product/multi-device-keyboard-k480?crid=26
- HHKB JP requires case modification for BT switch and LEDs.
    without switch power controlled by MCU? Probably using 3.3V regulator enable pin power of RN-42 can be controlled.

NOTE:
- LIPO BATTERY IS VERY DANGEROUS, TAKE EXTRA CARE OF YOUR SAFETY AND PROPERTY.
- RN-42 version 6.15 is supported.
- No NKRO over Bluetooth
- Check you country's wiress regulation and certification of RN-42.

Bugs:

Todos:


Lipo Battery
------------
You can use 3.7V Lithium Ion battery with JST PH 2pin connector and protection circuit.
Battery space inside HHKB is around 54mm x 50mm and its height is 7mm.

Sparkfun 850mAh
https://www.sparkfun.com/products/341
Sparkfun 1000mAh
https://www.sparkfun.com/products/339

Sparkfun 2000mAh battery won't fit due to its size.

Learn about Lipo battery:
https://learn.adafruit.com/li-ion-and-lipoly-batteries





LED Status
----------
Configuring                     10 times per sec
Startup/configuration timer     2 times per sec
Discoverable/Inquiring/Idle     once per sec
Connected                       solid on


RN-42 Magic Command
--------------------
Magic key combination is 'LShift+RShift' by default in case of HHKB.

Here is help.

    ----- Bluetooth RN-42 Help -----
    i:       RN-42 info
    b:       battery voltage
    Del:     enter/exit RN-42 config mode
    Slck:    RN-42 initialize
    p:       pairing
    u:       toggle Force USB mode

    RN-42 info:             displays information of the module on console.
    battery voltage:        displays current voltage of battery and uptime.
    RN-42 initialize:       does factory reset and configures RN-42
    pairing:                enters Pairing mode.
    toggle Force USB mode:  switch between USB and Bluetooth


RN-42 Config mode
-----------------
You can tune/operate RN-42 yourself with config(command) mode.

1. hook up USB cable
2. run `hid_listen` command  in console
3. turn on Bluetooth switch
4. press LShift+RShift+Delete(Fn+~) you will see output like followings:

    Entering config mode ...
    CMD
    v
    Ver 6.15 04/26/2013
    (c) Roving Networks

5. do config with RN-42 commands. See documentations of RN-42.
6. to exit also press LShift+RShift+Delete(Fn+~)

    Exiting config mode ...
    ---
    END


RN-42 Initial Configuration
---------------------------
RN-42 is configured as SPP device at factory reset, you need to configure it as HID device. This is needed just once first time.

1. hook up USB cable
2. run `hid_listen` command  in console
3. turn on Bluetooth switch
4. press LShift+RShift+ScrLk(Fn+O) you will see output like followings:

    Entering config mode ...
    CMD
    Ver 6.15 04/26/2013
    (c) Roving Networks
    ECHO ON
    SF,1
    AOK
    S-,TmkBT
    AOK
    SS,Keyboard/Mouse
    AOK
    SM,4
    AOK
    SW,8000
    AOK
    S~,6
    AOK
    SH,003C
    AOK
    SY,FFF4
    AOK
    R,1
    Reboot!
    Exiting config mode ...

5. output of command 'X' after cofiguration

    Ver 6.15 04/26/2013
    (c) Roving Networks
    ***Settings***
    BTA=00066667BBE9
    BTName=TmkBT-BBE9
    Baudrt(SW4)=115K
    Mode  =DTR
    Authen=1
    PinCod=1234
    Bonded=0
    Rem=NONE SET
    ***ADVANCED Settings***
    SrvName= Keyboard/Mouse
    SrvClass=0000
    DevClass=1F00
    InqWindw=0100
    PagWindw=0100
    CfgTimer=255
    StatuStr=NULL
    HidFlags=3c
    DTRtimer=8
    KeySwapr=0
    ***OTHER Settings***
    Profile= HID
    CfgChar= $
    SniffEna=8000
    LowPower=0
    TX Power=fff4
    IOPorts= 0
    IOValues=0
    Sleeptmr=0
    DebugMod=0
    RoleSwch=0


Switch to USB mode
------------------
You can switch between USB and Bluetooth with pressing 'LShift+RShift+u'.


Pairing mode
------------
This disconnects current connect and enter pairing mode.




For deveropment
===============

RN-42 Serial Connection
-----------------------
UART:           115200bps, 8bit, 1-stopbit, non-parity, no flow control
SSP:            115200bps, 8bit, 1-stopbit, non-parity, no flow control(via Bluetooth)

To enter command mode disconnect the module from host and type '$$$'.(you will see 'CMD') and type '+' to get local echo. To exit type '---'(you will see 'END').


RN-42 Commands
--------------
S-,tmkBT            // Device name
SS,keyboard/mouse   // service name
SM,4                // Auto Connect DTR mode
SW,8010             // Sniff enable 0x10*0.625ms=10ms; 50ms is laggish and not much power save
S~,6                // HID profile
S~,0                // SPP profile
SH,003C             // HID register
SY,0004             // Transmit power
SC,0000             // COD: 000005C0    (see HID spec/Bluegiga doc)
SD,05C0             //     bit 12-8         7           6           5-0
                    //         00101        1           1           0
                    //         peripheral   pointing    keybaord    joystick, gamepad, ...
SM,6                // Pairing mode: auto connect
SM,4                // Master mode: Connection can be controled with GPIO6
SF,1                // Factroy reset
R,1                 // reboot
SR,Z                // removes all remote addresses for reconnecting.
                    // can be used to connect another host
SR,I                // registers last inquiry address


Operation Modes
---------------
SM,3        Auto Connect Master mode
SM,4        Auto Connect DTR Mode uses GPIO6 to make and break connection(Mode =DTR)
                confirm: auto connect works and control connection with GPIO6
SM,5        Auto Connect ANY Mode (Mode =ANY)
                each time GPIO is set, make inquiry and connect to the first found device
SM,6        automatically reconnect(Mode =Pair)
                confirm: auto connect works well but difficult to enter command mode.


HID flag register
-----------------
SH,0200
GH

10 0000 0000(0200)  default
00 0011 1000(0038)  Combo
|| |  | |\_\____ number of paired devices to which the module can reconnect
|| |  | \_______ send out reports over UART (0xFF <len> <data>)
|| \__\_________ descriptor type
|\______________ toggle virtual keyboard on iOS when first connected
\_______________ Force HID mode if GPIO11 is high on power-up

    Descriptor type:
    0000:   keybaord
    0001:   Game Pad
    0010:   Mouse
    0011:   Combo
    0100:   Joystick
    1xxx:   reserved


Out report - Indicator
----------------------
0xFE 0x02 0x01 <LED_state>


Apple iOS
---------
Keyboard can be used with iPhone, but mouse cannot.


Android
-------
3.7.1.5 Note: To connect with Android phone the modules must wake up 11ms every 2.5seconds.


Power Management
----------------
Inquiry and Page window     Idle or Active  (3.1.1)
    Downside: delay in discovery or connection time
    SI,         // set inquiry scan window(discovery) on/off duty?
    SJ,         // set page scan window(connection)
    This reduces averaege power >20mA to 5mA(3mA in Sniff mode)

Sniff mode                  Transmit
    Sniff mode is disabled by default and radio is active continuously when connected.(25-30mA)
    In Sniff mode the radio wakes up intermittently and sleeps in very low power mode.(2mA)
    SW,<val>    // set interval timer(*0.625ms) 0000-7FFF

Deep sleep                  Idle            (3.1.2)
    In this mode the module shuts down completly and only draws about 300uA. To enable this set the most signifant bit(0x8000) of Sniff interaval timer.
    SW,8320     // deep sleep enable(interval=0x320*0.625=500ms)
    In normal sleep the firmware is still running in idle mode, and wakes up about 20 times per second to check ports, update LEDs, etc. During deep sleep, the firmware actually stops runnig some tasks and the LEDs only update about once per second.
    To wake from deep sleep there are three ways: (in worst case wake up takes 5ms)
        *send a charactor to the UART(first charactor will be lost)
        *toggle CTS low to high and wait 5ms
        *wake automatically every slot time(<val>*0.625ms)
    Once the radio is awake it stay active for exactly 1 second of inactivity and then sleeps again.
    Downside: latency and data loss

Disable Output driver       Idle or Active  (3.1.3)
    S%,1000     // set all GPIO pins(0-11) to inputs.

Lower Transmit Power        Idle or Active  (3.1.4)
    SY,<hex>    // transmit power setting(takes effect after a power cycle and reboot)
    Downside: reducing effective range


Optimizig for Latency
---------------------
By default the firmware is optimized for throughput.
SQ,16           // set latency bit
SQ,0            // unset latency bit


Configuration timer settings
----------------------------
Remote configuration is used for the module to be configured with various commands over Bluetooth(SPP profile only?).

The module has remote configuration timer to allow remote configuration over Bluetooth after power up in Slave mode. In Master modes the remote configuration timer is set to 0(no remote configuration). (In Trigger Master mode the timer is used as an idle timer to break the connection after time expires with no charactors receive.)
    ST,0        // no remote, no local when connected
    ST,<1-252>  // local and remote with timeout in seconds from power up
    ST,253      // local only       without timeout
    ST,254      // remote only      without timeout
    ST,255      // local and remote without timeout


Commands
--------
S7,                     7bit mode
SA,                     Authenticaiton
SB,                     Send break
SC,                     Service class
SD,                     Device class
SM,<val>                Operation mode
SP,<string>             Pin code(alpahnumeric)
SQ,<mask>               Special configuration(GPIO, discovery mode, low latency, reboot, UART)
SR,<hex>                Store remote address
SR,Z                    Erase all address
SS,<string>             Set service name(1-20)**
ST,<val>                Remote configuration timer(Master:0, Slave:0-255, Triger:as idle timer)
SU,<val>                UART baud rate
SW,<val>                low-power sniff mode** deep sleep and wake up every 625us * <val>
SX,<0|1>                bonding enable  only acceps device that matches the stored address
SY,<hex>                power setting**
SZ,<val>                non-standard raw baud rate  <val>=baud*0.004096
S~,<val>                Profile     0:SPP, 5:APL, 6:HID
S-,<string>             Device name     -15 alphanumeric charactors
S?,<0|1>                role switch enable
S$,<char>               command mode char
$|,<hex>                low-power connect mode  deep sleep/active(discoverable and connectable) cycle
D                       display basic setting
E                       display extended setting
GB                      display the device's Bluetooth address
GF                      display Bluetooth address of connected device
GK                      show connection status
GR                      show remote address for reconnecting
G&                      show GPIO pin
G<char>                 show stored setting
+                       toggle local echo on/off
&                       show GPIO 3,4,6,7(DIP switch)
C                       connect to stored remote address
C,<address>             connect last address
CFI                     connect and go into fast data mode
CFR                     connect and go into fast data mode
CT,<address>,<val>      connect to the address and disconnect after val?
F,1                     fast data mod:
H                       display help
I,<time>,<cod>          inquiry scan with <cod>
IN,<time>,<cod>         inquiry scan with <cod>, return without BT name
IR                      inquiry scan with 0055AA
IS                      inquiry scan with 001F00
J                       hide pin code
K,                      kill    disconnects current connection
L                       link quality
M                       show modem signlal status
O                       display other settings
P,<char>                pass through?
Q                       quiet mode  make the module not discoverable
Q,0                     discoverable and connectable
Q,1                     not discoverable and not connectable
Q,2                     not discoverable and connectable
Q,?                     display current quiet mode
R,1                     reboot
T,<0|1>                 pass received data while in command mode
U,<baud>,<parity>       change UART setting tentatively
V                       display firmware version
W                       wake from quiet mode    enable discovery and connection
Z                       deep sleep mode(<2mA)


Reset to Factory Default
------------------------
SF,1
R,1