Final energytrace commits. #98

bin/batterylife.py

@@ -0,0 +1,42 @@
+#!/usr/bin/python3
+
+## This is a quick little python script that takes the output of
+## energytrace-util, averages the current consumption for all samples
+## after ten seconds, and then predicts battery life from a 100mAH
+## CR2016 battery.
+
+## Usage: et 60 | python3 batterylife.py
+
+
+import sys;
+
+capacity=100 #mAH
+
+ampsum=0.0;
+ampcount=0;
+
+#Ugly shotgun parser to ignore comments and early records.
+for line in sys.stdin:
+    if line[0]=='#':
+        pass;
+    else:
+        words=line.split();
+        time=float(words[0]);
+        amps=float(words[1]);
+        milliamps=amps*1000.0;
+
+        #We only count after the first 10 seconds, as booting takes 5 seconds.
+        if time>10.0:
+            ampcount=ampcount+1;
+            ampsum=ampsum+amps;
+
+if ampcount>0:
+    ampavg=ampsum/(ampcount*1.0);
+    milliamp=ampavg*1000.0;
+    microamp=ampavg*1000000.0;
+    print("%f µA average consumption"%microamp);
+    hours=100/milliamp;
+    days=hours/24.0;
+    years=days/365.2425;
+    months=years*12.0;
+    print("%f months of CR2016 battery life."%months);

firmware/Makefile

@@ -125,7 +125,8 @@ dump:
 
 
 energytrace.txt: goodwatch.hex sbwflash
-	et 30 > energytrace.txt
+	et 60 > energytrace.txt #This will take a minute.
-
-energytrace.png: energytrace.txt energytrace.gnuplot
 	gnuplot energytrace.gnuplot
+	gnuplot energytrace-txt.gnuplot
+	../bin/batterylife.py <energytrace.txt
+

firmware/energytrace-txt.gnuplot

@@ -0,0 +1,11 @@
+
+set terminal dumb
+
+set title "GoodWatch Current Consumption" font ",20"
+set xlabel "Seconds"
+set ylabel "Current"
+set yrange [0:10e-06]
+set xrange [20:25]
+
+plot "energytrace.txt" with lines;
+