Update doc

2 files changed, 128 insertions, 451 deletions

diff --git a/keyboard/hhkb_rn42/MEMO.txt b/keyboard/hhkb_rn42/MEMO.txt
index e623c0013..f2aaa7c04 100644
--- a/keyboard/hhkb_rn42/MEMO.txt
+++ b/keyboard/hhkb_rn42/MEMO.txt
@@ -4,7 +4,7 @@ Roving RN-42
 Bug:
 - with Nexus5 keyboard and mouse are very laggy.
 
-- lose USB connection during power-down mode
+- lose USB connection during power-down mode - DONE
     - USB initialize code in main() causes this - WRONG
     - Do not power-down during USB connection is active - DONE 11/11
         (USB_DeviceState == USB_DEVICE_Configured) is used to check USB connection
@@ -18,7 +18,7 @@ Bug:
     - time out interrupt is lost while power down?
     - interrupt of watchdog timer compensates timer counter(avr/suspend.c)
 
-- USB plug-in while BT failes
+- USB plug-in fails while BT
     - it ends in suspend state
     - maybe, not responsive to host enumeration process due to power-down.
     - matrix_power_down() only when state is unattached - 11/26
@@ -26,19 +26,49 @@ Bug:
 - repeated CHARGING/FULL_CHARGED
     - In LTC sharp pulses are observed.
     - MCP has no pulse but still has a problem.
-    - needs more wait before read pin state?
-- wrongly suspended when powered from adapter without USB connection
+    - needs more wait before read pin state? - NO
+- wrongly suspended when powered from adapter without USB connection - DONE
     - suspend event may occur when plug into adapter
     - and never wake until conected to real USB line
     - without debug print via USB no problem; CSW(wake just after suspend as real USB line)
     - seems like USB print causes this problem after suspended
 
+- Factory Reset PIO4 doesn't work
+    - the reason is unclear - 12/08 NOT LOOK INTO ANY MORE
+    - WORKAROUND: use serial pins(3.3V, GND, RX and TX)
+        - SF,1 and R,1 to set factory defalult
+    
+
 Todo:
-- sendchar() in lufa.c block loop   - 11/29
-    - block loop when powered with AC adapter
-    - FrameNumber is not updated when adapter powered
+- LED cover and switch knob and new Slide Switch
+- RN42 auto configuration
+    - configure the module as HID device every time powering up
+    - this'll reduce work load of assembly
+
+- move rn42 to protocol directory when it becomes reusable stack
+
 - sendchar() in lufa.c no buffer
     - no buffering. character lost can be caused.
+- LUFA sendchar should be buffered and serial_uart.c buffur size is too large(256).
+
+- switch BT host connections
+- BT operations
+    - disconnect
+    - new connection
+    - switch next connection
+    - remove connection
+
+- sendchar() in lufa.c block loop   - DONE 11/29
+    - block loop when powered with AC adapter
+    - FrameNumber is not updated when adapter powered
+
+Improving:
+- ADC resolution
+    AVR120
+    AVR32138
+    - Enhancing ADC resolution by oversampling
+        AVR121  http://www.atmel.com/images/doc8003.pdf
+    - disable digital input buffer DIDR(7.8.6)
 
 Design:
 - suspend.h - DONE 11/26
@@ -85,6 +115,24 @@ USB connection check: state of USB deivce
 
 
 Power saving:
+- Pro2 current consumption
+    - active: 138.2mA(no device on Hub)
+    - suspended: 30.9mA(WakeUp enabled DIPSW6)
+    - suspended: 0mA->46.0mA(WakeUp disabled DIPSW6)
+- Pro current consumption
+    - active: 54.0mA
+    - suspended: 40.5mA(WakeUp enabled DIPSW6)
+    - suspended: 0.3mA(WakeUp disabled DIPSW6)
+
+- RN42 3.3V
+    - disconnected(Idle): 5mA (config mode)
+    - connected(Active):
+        SW,0000:  23-26mA
+        SW,0010:  27-29mA worse than 0000 for unknown reason
+        SW,0020:  17-19mA mouse NG
+        SW,0030:  13-16mA laggy mouse NG
+        SW,0050:  10-13mA laggy mouse NG
+
 - matrix power saving
     - power saving while externally powered and not while unpluged
 - confirm suspend mode lufa.c: matrix_power_*, suspend_wakeup_condition
@@ -105,135 +153,11 @@ Power saving:
 - Suspend: Clear Suspend Bit, Freeze clock, disable PLL, MCU sleep(21.13)
 - Voltage reference(8.1.1)
     - to reduce power consumption while power down mode
-
-Improving:
-- BT LED; connecting, linked, sleeping, deep sleeping
-- Battry LED; blink(using timer?)
-- move rn42 to protocol directory when it becomes reusable stack
-- LUFA sendchar should be buffered and serial_uart.c buffur size is too large(256).
-- ADC resolution
-    AVR120
-    AVR32138
-    - Enhancing ADC resolution by oversampling 
-        AVR121  http://www.atmel.com/images/doc8003.pdf
-
-
-Testing:
-- Factroy reset doesn't work; need to **test again** 10K pull-up is too high?
-- Lipo voltage ADC value is not stabilized
-- DCDC converter: squeaky inducter; try other inductors
-
-- Keymap layer bug: during space is pressed(mousekey) press Fn(HHKB) then release space before Fn, in result HHKB layer is locked(toggled) unintentionally.
-
-
-Done:
-- low battery alert(solid light) 09/04
-
-
-Power routing
--------------
-Current:
-(USB)   +---(Lipo)
- |      |     |
- |      |  +------+     DPDT
- |      |  |Switch/-----------------------+
- |      |  +------+                       |
- | +-------+  |                           |
- +-|Charger|  |                           |
- | +-------+  |     +---+                 |
- |            |     |MCU|                 |
- |            |     +---+                 |
- |            |      |                    |
- |            |      |                    |
-+--------------+  +-----+  +------+   +---/--+    +-----+
-|Power Selector|--|DC 5V|--|DC3.3V|---|Switch|----|RN-42|
-+--------------+  +-----+  +------+   +------+    +-----+
-USB Power is boosted unnecessarily, not harmful?
-
-Idea 1:
-(USB)   +---(Lipo)
- |      |     |
- |      |  +------+     DPDT
- |      |  |Switch/----------+
- |      |  +------+          |
- | +-------+  |              |
- +-|Charger|  |              |
- | +-------+  |     +---+    |
- |         +-----+  |MCU|    |
- |         |DC 5V|  +---+    |
- |         +-----+   |       |
- |            |      |       |
-+--------------+     |   +---/--+    +------+     +-----+
-|Power Selector|-----+---|Switch|----|DC3.3V|-----|RN-42|
-+--------------+         +------+    +------+     +-----+
-To enable BT when USB powered it still needs to turn siwtch on, Lipo consumes quinscent current at 5V converter in vain.(Not good)
-
-Idea 2:
-(USB)   +---(Lipo)
- |      |     |
- |      |  +------+
- |      |  |Switch|
- |      |  +------+
- | +-------+  |
- +-|Charger|  |
- | +-------+  |     +---+
- |         +-----+  |MCU|----+ Controlled by firmware
- |         |DC 5V|  +---+    | On: Lipo powered
- |         +-----+   |       | Off: USB powered
- |            |      |       |enable
-+--------------+     |   +------+     +-----+
-|Power Selector|-----+---|DC3.3V|-----|RN-42|
-+--------------+         +------+     +-----+
-MCU can controlled power of RN-42 without hardware switch.
-When USB powered and switch is on Lipo consumes quinscent current at 5V converter in vain.(Not good)
-
-Idea 3:
-(USB)   +---(Lipo)
- |      |     |
- |      |  +------+
- |      |  |Switch|SPST(or without)
- |      |  +------+
- | +-------+  |
- +-|Charger|  |
- | +-------+  |     +---+
- |            |     |MCU|----+ Controlled by firmware
- |            |     +---+    | On: Lipo powered
- |            |      |       | Off: USB powered
- |            |      |       |enable
-+--------------+ +-----+ +------+     +-----+
-|Power Selector|-|DC 5V|-|DC3.3V|-----|RN-42|
-+--------------+ +-----+ +------+     +-----+
-Switch is needed to save Lipo when not used because decent power saving is not available now. If firmware can turn off BT module completely and make MCU deep sleep the switch will be not even needed.
-
-
-
-
-
-DONE:
-- BT_INDICATOR LED turns on wrongly when touching line or pin.  -- pull-up enabled on PF6/GPIO2 08/30
-- Lipo charger configuration: fast charge time:  USB charger spec? -- used 2kohm
-- use LED of charger to alarm low battery. LED should be powered directly from Lipo? - cancel; powered from VUSB
-- Use RTS in serial_uart.c to resolve missing chars from help message of RN-42 - done
-- CTS/RTS lines are needed? just connect in loop back if no flow control is needed. - done
-- add IO pin to charger status CHRG; LED control(low) and detect charge status(input HiZ) 07.24
-- LINKED: add trace on PIO2 to PF6   07.24
-- Lipo voltage ADC sensing
-- Lipo charger MCP73831: needs capacitor 4.7uF *2
-- USB connection check - 07.01
-- BT on/off check: whether RX line is pulled up? - checking RTS 07.01
-- USB/BT switching  BT is on -> BT, BT is off -> USB - 07.01
-- Under voltage lock out UVLO for protection of Lipo - Lipo has discharge protection at 3.100V    07.01
-- Power saving: HHKB scan, BT radio control - 9h with 850mAh, this is enough   07.01
-- Power selector doesn't work; Q4 MOSFET leaks from Lipo to USB power line. -- use Schottky instead 07/04
+- unset ADEN before sleep(24.7)
 
 
 
-TROUBLE SHOOT
--------------
-07/16   After fix of voltage dividor on GPIO6, had a trouble that it could not send a char to BT module, though could receive.
-        Found R8 had wrong 1K resistor and changed to 10K, after that it can send to the module again. Not sure how it had sent with the wrong 1K before.
 
-07/18   On Linux, had an USB related trouble; keyobard or console didn't work for some reason. Changing PID cured this problem. Very annoying, took very long time before resolved it.
 
 
 
@@ -249,7 +173,7 @@ Protection spec:
 http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/BatteryProtection.pdf
                                 min     typical max
     over-charge                 4.255   4.280   4.305
-    over-charge discover?       4.030   4.080   4.130        
+    over-charge discover?       4.030   4.080   4.130
     over-discharge              2.827   2.900   2.973
     over-discharge discover     3.022   3.100   3.178
 
@@ -260,325 +184,65 @@ ADC voltage monitor:    voltage divider 10K+10K(0.5)
     ------------------
     4.20    0x347(839)
     3.10    0x26b(619)
-    
 
 
 
-Configuration
+
+TROUBLE SHOOT
 -------------
-Ver 6.15 04/26/2013
-(c) Roving Networks
-***Settings***
-BTA=0006664B3AE3
-BTName=tmkBT-3AE3
-Baudrt(SW4)=115K
-Mode  =DTR
-Authen=2
-Bonded=0
-Rem=000000000000
-***ADVANCED Settings***
-SrvName= keyboard/mouse
-SrvClass=0000
-DevClass=0000
-InqWindw=0100
-PagWindw=0100
-CfgTimer=255
-StatuStr=NULL
-HidFlags=3c
-DTRtimer=8
-KeySwapr=0
-***OTHER Settings***
-Profile= HID
-CfgChar= $
-SniffEna=8010
-LowPower=0
-TX Power=0
-IOPorts= 0
-IOValues=0
-Sleeptmr=0
-DebugMod=0
-RoleSwch=0
-
-
-
-Serial connection
------------------
-Serial line:    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')
-To exit type '---'(you will see 'END') and '+' to get local echo.
-
-
-
-Setting command mode
---------------------
-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
-SH,003C             // HID register
-SY,0004             // Transmit power
-
-
-
-
-Other options:
-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
-
-
-
-
-HID profile
------------
-S~,6    HID profile
-S~,0    SPP profile
-R,1     reboot
-
-
-Apple iOS
----------
-Keyboard can be used with iPhone, but mouse cannot.
-To operate iOS with keyboard is not so useful, though.
-There may be iOS specific scancodes?
-
-
-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.
-
-SR,Z        removes all remote addresses for reconnecting.
-                can be used to connect another host
-SR,I        registers last inquiry address
-
-
-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*0.625=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
-
-
-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)
-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
-IQ                      scan
-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,<car>                 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)
-
-
-
-help
-----
-*** SET COMMANDS ***
-SA,<3,0>   - Authentication
-SC,<hex>   - Service Class
-SD,<hex>   - Device Class
-SE,<1-16>  - UUID
-SF,1       - Factory Defaults
-SH,<hex>   - HID flags
-SI,<hex>   - Inquiry Scan Window
-SJ,<hex>   - Page Scan Window
-SL,<E,O,N> - Parity
-SM,<0-5>   - Mode (0=slav,1=mstr,2=trig,3=auto,4=DTR,5=Any)
-SN,<name>  - Name
-SO,<text>  - conn/discon Status
-SP,<text>  - Pin Code
-SR,<adr>   - Remote Address
-SS,<text>  - Service Name
-ST,<num>   - Config Timer
-SU,<rate>  - Baudrate
-SW,<hex>   - Sniff Rate
-SX,<1,0>   - Bonding
-SY,<hex>   - TX power
-SZ,<num>   - Raw Baudrate
-S~,<0-6>   - Profile (0=SPP,1=DCE,2=DTE,3=MDM,4=D&S,6=HID
-S?,<0-1>   - role switch
-S$,<char>  - CMD mode char
-S@,<hex>   - io port dir
-S&,<hex>   - io port val
-S%,<hex>   - io boot dir
-S^,<hex>   - io boot val
-S*,<hex>   - pio(8-11) set
-S|,<hex>   - low power timers
-S+,<num>   - DTR timer
-S=,<hex>   - Key mapper
-S:,<num>   - sleep timer
-*** DISPLAY      ***
-D     - Basic Settings
-E     - Extended Settings
-G<X>  - Stored setting
-GB    - BT Address
-GF    - BT Address of Last Connection
-GK    - Connect Status
-G&    - I/O Ports
-V     - Firmare version
-*** OTHER        ***
-C,<adr>    - Connect
-F,1        - Fast Mode
-I,<time>,<cod> - Device Scan Inquiry
-J          - Hide Pin Code
-K,         - Kill (disconnect)
-L,         - toggle local echo
-P,<text>   - Pass Thru
-Q          - Quiet (no discovery)
-R,1        - Reboot
-T,<0,1>    - send data in CMD mode
-U,<rate>,<E,O,N> - Temp Uart Change
-Z          - low power sleep
-&          - Read switches
+07/16   After fix of voltage dividor on GPIO6, had a trouble that it could not send a char to BT module, though could receive.
+        Found R8 had wrong 1K resistor and changed to 10K, after that it can send to the module again. Not sure how it had sent with the wrong 1K before.
+
+07/18   On Linux, had an USB related trouble; keyobard or console didn't work for some reason. Changing PID cured this problem. Very annoying, took very long time before resolved it.
+
+12/07   rn42_rts() read 1 every time. R12 broke in open mode(no coductive), idk why, too much heat with soldering? and PF1 pin was not soldered.
+        It resolved with resoldering PF1 and new resistor on R12.
+
+
+
+
+Done:
+- low battery alert(solid light) 09/04
+- *** Rev.E BT test *** - DONE
+    - with MCP73832, new Schottky, tantalum caps - DONE 12/07
+        * MCP73832 doesn't leak from Vcc pin when unpluged and battery powered
+            34mV vs 2.07V(MCP73831) at Vcc pin
+            MCP73832 doesn't need revese protection diode D5
+        * PMEG2010ER is very low VF while reverse current/voltage is high
+            VF=0.96 vs 1.98(RB160M-30TR)with Fluke 175
+            Anode of D11 is 680mV vs 20mV(RB160M-30TR)
+            780mV is still low < 1.4V VBUS plugin detection(21.11)
+                this doesn't cause false VBUS detect
+                and 780mV on MCP73832 Vcc pin is also no problem.
+            D5 can be removed.
+    - ADC divider switching - DONE 12/07
+        * Drain and Source of Q4 Pch was reversed wrongly on Rev.E.
+
+    - reverse current from Lipo charger - DONE 12/07
+        * MCP73832 has no recverse current from Vcc pin unlike MCP73831
+
+
+- Rev.F design - DONE
+    - current measure point - DONE 12/08
+    - change value of cap 68->47    - DONE 12/08
+    - PPTC land pattern: no solder jumper, use 0Ohm resistor instead - CANCEL 12/08
+    - Q4 Pch FET: wrong Drain and Source - DONE 12/08
+    - D5 can be removed.    - DONE 12/08
+
+
+
+- BT_INDICATOR LED turns on wrongly when touching line or pin.  -- pull-up enabled on PF6/GPIO2 08/30
+- Lipo charger configuration: fast charge time:  USB charger spec? -- used 2kohm
+- use LED of charger to alarm low battery. LED should be powered directly from Lipo? - cancel; powered from VUSB
+- Use RTS in serial_uart.c to resolve missing chars from help message of RN-42 - done
+- CTS/RTS lines are needed? just connect in loop back if no flow control is needed. - done
+- add IO pin to charger status CHRG; LED control(low) and detect charge status(input HiZ) 07.24
+- LINKED: add trace on PIO2 to PF6   07.24
+- Lipo voltage ADC sensing
+- Lipo charger MCP73831: needs capacitor 4.7uF *2
+- USB connection check - 07.01
+- BT on/off check: whether RX line is pulled up? - checking RTS 07.01
+- USB/BT switching  BT is on -> BT, BT is off -> USB - 07.01
+- Under voltage lock out UVLO for protection of Lipo - Lipo has discharge protection at 3.100V    07.01
+- Power saving: HHKB scan, BT radio control - 9h with 850mAh, this is enough   07.01
+- Power selector doesn't work; Q4 MOSFET leaks from Lipo to USB power line. -- use Schottky instead 07/04
diff --git a/keyboard/hhkb_rn42/PowerSave.txt b/keyboard/hhkb_rn42/PowerSave.txt
index 943923c33..9aa89f441 100644
--- a/keyboard/hhkb_rn42/PowerSave.txt
+++ b/keyboard/hhkb_rn42/PowerSave.txt
@@ -1,6 +1,19 @@
 RN-42
 =====
 
+
+12/11
+Power Comsumption
+MCU+HHKB
+--------
+Battery drive:
+    idle    18.9mA
+    active  35.8mA
+
+USB powered:
+    40.0mA
+
+
 HHKB key switch power control
 -----------------------------
 MOS FET Nch: BSS138 or IRLML6344T, either works and no apparent difference.