- 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.
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.
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)
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
tmk
10 years ago