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For those that don't follow the 43oh Blog: @@Fmilburn published a great write-up about how to use EnergyTrace to measure and improve power consumption and battery life of an Energia sketch. The article includes a nice demonstration of the effectiveness of sleep() vs. delay(). http://43oh.com/2015/09/how-to-measure-an-energia-applications-power-usage-with-energytrace/ He also shows how an EnergyTrace compatible LaunchPad (e.g. FR5969) can be used to measure power consumption of an older LaunchPad (e.g. G2553). This probably works for standalone projects as well.
Finally I'll share some of my binary watch project with you guys. Some features: - 11 LEDs charlieplexed on 2x 3 I/O pins (6 LEDs per 3 I/O lines, one LED not placed) - As low power as can get (900 nA in stand-by) - 14-pin value lin MSP430 - watch crystal sourced (32768Hz) - two buttons (of which one is on the reset line) - well under 2kB code (1.6kB) The "display refresh rate" is 512Hz, which makes the "pixel refresh rate" at 85Hz, a comfortable rate for the eye. The WDT is used as a minute timer (2 second hardware, 30 iterations in software), sourced from the crystal, I go down to LPM3 then and can run at 900 nanoAmps. During display I run in LPM1 from which I wake 512 times per second to update the LED display. The reset line is reused as an input line for one of my two buttons, using the NMI I can use it as a reliable button input pin using some nifty software tricks. I use the reset line as button input because I ran out of I/O (10 available: 6 for the display, 1 for a button, 2 for the crystal and 1 for a future buzzer) I'm busy desiging a PCB for this too (not a booster, a feature complete board). Using a coincell/buttoncell battery I can fit all my components (except the battery and buzzer) on a 11x39mm PCB, targeting for 20x20mm now.