Dump OBDII Info via cansend and candump

obdii_info.sh

# --------- SCRIPT BEGIN ----------
# By Bret Stateham
# This script assumes
# - You are running on a linux machine
# - You have the can-utils installed and working.  See:
#   - https://github.com/linux-can/can-utils
#   - https://www.kernel.org/doc/Documentation/networking/can.txt
# - You have a can device attached and configured as can0 (you can change the targetbus variable to match if otherwise)
# - The can device is attached to your running target vehicle

# This script uses bc - An arbitrary precision calculator language. You may need to install it with "sudo apt-get install -y bc" 

targetbus="can0"

zero_pad() {
  # stolen from: https://unix.stackexchange.com/a/145659
  # zero_pad <string> <length>
  [ ${#1} -lt $2 ] && printf "%0$(($2-${#1}))d" ''
  printf "%s\n" "$1"
}

echo ""
echo "Requesting the vehicle's VIN"
echo ""

# start candump in the background and capture it's process id
candump $targetbus,7DF:7FF,7E0:7E0 > vin.log &
vindumpprocid=$!

# Request the VIN, and send the flow control message to get all frames
cansend $targetbus 7df#0209020000000000 
sleep 0.01 
cansend $targetbus 7e0#3000000000000000
sleep 1

# kill the vin candump
kill -s SIGINT $vindumpprocid

echo ""
echo "Requesting all Service 01 PIDS"
echo ""


# start candump in the background and capture it's process id
candump $targetbus,7DF:7FF,7E0:7E0 > pids.log &
allpiddumpprocid=$!

# Valid PID hex values are 00 to E0 or in decimal 0 to 224
for pid in {0..224}
do
   pidhex=$(echo "obase=16;$pid" | bc)
   pidhexstr=$(zero_pad "$pidhex" 2)
   #echo $pidhexstr
   canprefix="7DF#0201"
   cansuffix="0000000000"
   canpayload="$canprefix$pidhexstr$cansuffix"
   echo $canpayload
   cansend $targetbus $canpayload
   # Delay for a bit to keep from flooding the bus
   sleep 0.05
done

# kill the candump
kill -s SIGINT $allpiddumpprocid


echo ""
echo "Requesting Service 01 PIDS that return multi-frame messages"
echo ""


# ok, now loop through the pids.log file created above, and look
# Lines that have a data payload that starts with #1 indicate the
# first frame in a multi-frame sequence.  We need to capture the ID
# of the sender of that message (the hex value to the left of the #)
# as well as the PID (the 5-6 digits to the right of the #) that was 
# initially requested.
# We then need to requery the PID (on 7DF) and then after a short 
# (like .02 second) delay, follow up with the 7EX#30000000000000 flow
# control message where 7EX is the hex id minus eight we calculated above

# Example line:
# can0  7E8   [8]  10 09 41 68 03 4A 52 00

# start candump in the background and capture the extended messages
candump $targetbus,7DF:7FF,7E0:7E0 > pids_extended.log &
extpiddumpprocid=$!

while read line; do
  ln=$(echo $line | tr -s ' ')
  firstbyte=$(echo $ln | cut -d' ' -f4)
  if [ "$firstbyte" == "10" ]
  then
      echo $line
      sourceid=$(echo $ln | cut -d' ' -f2)
      targetpid=$(echo $ln | cut -d' ' -f7)
      flowid=$(echo "obase=16;ibase=16;$sourceid-008" | bc)
      querypre="cansend $targetbus 7DF#0201"
      querypost='0000000000'
      querycmd=$querypre$targetpid$querypost
      flowpre="cansend $targetbus "
      flowpost='#3000000000000000'
      flowcmd=$flowpre$flowid$flowpost
      echo $querycmd
      eval $querycmd
      sleep 0.01
      echo $flowcmd
      eval $flowcmd
  fi
done < pids.log

# kill the candump
kill -s SIGINT $extpiddumpprocid


echo ""
echo "Requesting the vehicle's DTCs (Diagnostic Trouble Codes)"
echo ""

# start candump in the background and capture it's process id
candump $targetbus,7DF:7FF,7E0:7E0 > dtcs.log &
dtcdumpprocid=$!

# Request the DTCs, and send the 0x7E0 flow control message to get all frames
# from 0x7E8
cansend $targetbus 7df#0103000000000000 
sleep 0.01 
cansend $targetbus 7e0#3000000000000000
sleep 1

# kill the vin candump
kill -s SIGINT $dtcdumpprocid

#combine the two logs into a single file
rm obdii_info.txt 2> /dev/null

echo "##########       VEHICLE  VIN       ##########" >> obdii_info.txt
cat vin.log >> obdii_info.txt
echo "##########     ALL PID REQUESTS     ##########" >> obdii_info.txt
cat pids.log >> obdii_info.txt
echo "########## MULTI-FRAME PID REQUESTS ##########" >> obdii_info.txt
cat pids_extended.log >> obdii_info.txt
echo "##########       VEHICLE DTCs       ##########" >> obdii_info.txt
cat dtcs.log >> obdii_info.txt
rm vin.log pids.log pids_extended.log dtcs.log

echo ""
echo "All pid messages (including multi-frame messages) have been logged to:"
echo ""
echo "obdii_info.txt"
echo ""
cat obdii_info.txt
# ---------  SCRIPT END  ----------