- DCDC converter: squeaky inducter with onsemi NCP1402
- Lipo charger MCP73831: needs capacitor 4.7uF *2
- Keymap layer bug: during space is pressed(mousekey) press Fn(HHKB) then release space before Fn, in result HHKB layer is locked(toggled) unintentionally.
SM,4 // Master mode: Connection can be controled with GPIO6
SY,FEE8 // lower power -20dbM
HID profile
-----------
S~,6 HID profile
S~,0 SPP profile
R,1 reboot
Apple iOS
---------
Cannot supported without apple iAP authentication chip.
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>
LED Status
----------
Configuring 10 times per sec
Startup/configuration timer 2 times per sec
Discoverable/Inquiring/Idle once per sec
Connected solid on
Pairing
-------
First, host initiates pairing process and once it is done, auto connect will work thereafter.
SM,3 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.
Fast data mode
--------------
The module enters fast data mode after 'remote configuration timer' window is passed from power on.
In this mode the module does not accept '$$$' to enter command mode.
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*0.625ms)
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
Android
-------
3.7.1.5 Note: To connect with Android phone the modules must wake up 11ms every 2.5seconds.
Commands
--------
SC,
SM,<val>
SD,
SP,<string> Pin code(alpahnumeric)
SQ,<mask> Special configuration(GPIO, discovery mode, low latency, reboot, UART)
