- deep sleep MCU and BT module(keyboard is not used for long time)
- deep sleep MCU and turn off BT module(keyboard is not used and not connected)
- Battery ADC; switching, high resistance
+ - switching gnd end of divider with PF4
+ - high resistor 100K/1M?
+ capacitor 10nF
+ http://www.eevblog.com/forum/beginners/measuring-battery-voltage-without-consuming-current/
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
Testing:
- Factroy reset doesn't work; need to **test again** 10K pull-up is too high?