fixed CPU usage script, added some lines to README

README.md

@@ -21,7 +21,7 @@ How to use:
 4. Edit rpisystat.py to match your network adapter (eth0 or wlan0)
 5. Edit rx.sh and tx.sh to match your network adapter (eth0 or wlan0)
 6. Run rpisystat.py
-
+7. chmod +x *.sh *.py
 For detailed instructions, check my blog post (coming soon).
 
 Video: https://www.youtube.com/watch?v=5YkLTBd5-bw

cpu_usage.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+awk -v a="$(awk '/cpu /{print $2+$4,$2+$4+$5}' /proc/stat; sleep 1)" '/cpu /{split(a,b," "); print 100*($2+$4-b[1])/($2+$4+$5-b[2])}'  /proc/stat

rpisystat.py

@@ -45,14 +45,14 @@ def run_cmd(cmd):
 # Rpi GPU temperature
 cmd4 ="/opt/vc/bin/vcgencmd measure_temp | cut -c 6- | cut -c -4"
 
-# CPU usage - print s/4 means divided by four (number of cores)
-cmd5 = "top -bn 1 | awk 'NR>7{s+=$9} END {print s/4}'"
+# CPU usage
+cmd5 = "bash cpu_usage.sh"
 
 # Memory usage 
 cmd6 = "free | awk 'FNR == 3 {print $3/($3+$4)*100}' | cut -c -3"
 
 # Get free disk space
-cmd7 = "df -h | awk 'NR==2 { print $3 }'"
+cmd7 = "df -h | sed -n 2p | awk '{ printf $4 }'"
 
 # Calculate RX rate
 cmd8 ="bash rx.sh"