Changes between Version 5 and Version 6 of TipsAndTricks

Timestamp:

2014-01-24 06:51:30 (11 years ago)

Author:

axill

Comment:

case 3 from MDoc about battery power added

TipsAndTricks

@@ -48 +48 @@
 ----
 
+== Case # 3==
+
+'''Powering things from battery'''
+
+'''Task:'''   ''Tips to achieve long battery life.  This consolidates information from a great post from @a-lurker and others around the web trying to the longest battery life possible.''
+http://forum.micasaverde.com/index.php/topic,20078.0.html
+
+'''Solution:'''
+1.   Disable or remove  the on-board regulator.  This draws excessive current;
+2.   Remove the power LED.  On some boards this is done by disabling the Regulator;
+3.   Power directly off the battery or use a Switching Regulator such as:
+https://www.sparkfun.com/products/10967
+
+http://www.pololu.com/product/798
+4.   SLEEP whenever possible. 
+- Wake up using the WDT
+
+{{{
+sleep.sleepDelay(SLEEP_TIME * 1000); //sleep for: sleepTime
+}}}
+- Or use an interrupt if using a button or sensor.
+See http://code.mios.com/trac/mios_arduino-sensor/browser/VeraArduino/Arduino/libraries/Vera/examples/RelayWithButtonActuator/RelayWithButtonActuator.ino
+5.   Disable the BOD (Brow out detection).  Sleep library does this or can be done in software:
+<Enter Sleep Mode>
+
+{{{
+// turn off brown-out enable in software
+MCUCR = bit (BODS) | bit (BODSE);
+MCUCR = bit (BODS);
+}}}
+<Sleep the CPU  within 3 clock cycles of above code>
+6. Turn of A/D Convertors :  (Again Hek already does this in Sleep Library)
+
+{{{
+// disable ADC
+ADCSRA = 0;
+}}}
+7.   Set unused input or output pins to LOW;
+8.   Lower your clock frequency. This has to be done by burning your fuses. Be careful and check the clock frequency of the radio you're using;
+9.   To send the Battery level to the Gateway:
+To measure the battery internally (when connected directly to a battery):
+{{{
+// Read the Battery
+long readVcc() {
+    long result;
+    // Read 1.1V reference against AVcc
+    ADMUX = _BV(REFS0) | _BV(MUX3) | _BV(MUX2) | _BV(MUX1);
+    delay(2); // Wait for Vref to settle
+    ADCSRA |= _BV(ADSC); // Convert
+    while (bit_is_set(ADCSRA,ADSC));
+    result = ADCL;
+    result |= ADCH<<8;
+    result = 1126400L / result; // Back-calculate AVcc in mV
+    return result;
+}
+}}}
+{{{
+// Send the Battery Percentage to the Gateway
+#define VBatMax 3.1             // The voltage of New Batteries
+#define VBatDropout  1.8    // The battery dropout voltage
+gw.sendBatteryLevel((readVcc()-(Dropout*1000)) /(((VBatMax-Dropout) *10)));
+}}}
+
+To measure the battery voltage when using a Switching Regulator:
+See a-lurker's post: http://forum.micasaverde.com/index.php/topic,20078.0.html
+
+'''Comments:'''
+
+For reference here are some good sights:
+
+http://maniacbug.wordpress.com/2011/10/19/sensor-node/
+
+http://www.gammon.com.au/forum/?id=11497
+
+http://hwstartup.wordpress.com/2013/03/11/how-to-run-an-arduino-on-a-9v-battery-for-weeks-or-months/
+
+http://hwstartup.wordpress.com/2013/04/15/how-to-run-an-arduino-clone-on-aa-batteries-for-over-a-year-part-2/
+
+http://www.thalin.se/2013/04/arduino-pro-mini-low-power-modification.html
+
+http://www.rocketscream.com/blog/2011/07/04/lightweight-low-power-arduino-library/
+
+----
+
 ... more cases to came soon