ConnectedCar

Setup Setps

Pair Bluetooth connection (laptop/raspi ) with OBD-II - use passcode 1234

python script.py <sleep_duration>

Set up Raspi  internet connection

 sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev

update_config=1

country=IE

network={

     ssid="eir1111111"

     psk="xfvgsdgd"

     key_mgmt=WPA-PSK

     priority=1

}

network={

    ssid="Am2222222"

    psk="dfhjgdfkjh"

    key_mgmt=WPA-PSK

    priority=2

}

Restart the network interface to apply the changes:

sudo wpa_cli reconfigure

sudo ifdown wlan0

sudo ifup wlan0

Install Libs  in laptop or Raspi

 sudo apt-get update

sudo apt-get install python3-pip gpsd gpsd-clients

pip3 install obd gpsd-py3 paho-mqtt

SETUP Serial UART Connection with Raspi 

In current set up GPS Module is connected to uart connections that should be read from a serial connection to do this 

Remove Serial Console from /boot/cmdline.txt

Ensure that the serial port is available for your GPS module, you should remove the serial console settings from the cmdline.txt file.

sudo nano /boot/cmdline.txt

• Find the part that reads console=serial0,115200 and delete it. Make sure not to change any other part of this line.

• Save and exit

• sudo reboot

Verify changes 

dmesg | grep tty

You should not see any references to ttyAMA0 or serial0 being used for the console.

To ensure that your Raspberry Pi uses ttyAMA0 for your GPS module and that all settings are correctly configured, you will need to make adjustments in both /boot/cmdline.txt and /boot/config.txt. Here's a detailed guide on how to do this:

1. Edit /boot/cmdline.txt

The /boot/cmdline.txt file contains parameters that are passed to the Linux kernel at boot. It's important to remove any references to serial consoles that might be using ttyAMA0 or any UART.

Look for any text that includes console=serial0,115200 or console=ttyAMA0,115200. If found, delete these segments to prevent the kernel from using the UART as a console . this should be already done in previous steps 

Edit /boot/config.txt

The /boot/config.txt file is used to set various boot and hardware configuration options. To ensure ttyAMA0 is available for general use, you need to make sure it is not being used by the Bluetooth module on Raspberry Pi models that have Bluetooth (such as the Raspberry Pi 3 and later).

update result

[all]

 enable_uart=1 

dtoverlay=w1-gpio 

gpu_mem=128

dtoverlay=miniuart-bt

This configuration swaps the Bluetooth module to ttyS0, which is less reliable for data transmission but keeps Bluetooth functional.

Use terminal tools like minicom or screen to directly test the serial communication:

sudo apt-get install minicom

sudo minicom -b 9600 -o -D /dev/ttyS0

SETUP Connections 

BN-220 GPS Module          Raspberry Pi 3 Model B

-----------------          ---------------------

       VCC      ---------->      5V (Pin 2)

       RX       ---------->      GPIO14 (TXD) (Pin 8)

       TX(white)       ---------->      GPIO15 (RXD) (Pin 10)

       GND      ---------->      GND (Pin 6)

Note : if you swap RX or TX e.g RX of BN-220 connect to GPIO15 , u will see the blue light will stop blinking - NOT CORRECT . make sure the RX and TX for BN is correctly connected to Raspi

Code

import obd

import gpsd

import time

import json

import paho.mqtt.client as mqtt

import sys

# Connect to the OBD-II adapter

obd_connection = obd.OBD()  # Auto-connects to USB or Bluetooth

# Connect to the GPS module

gpsd.connect()

# MQTT configuration

MQTT_BROKER = "your_mqtt_broker_address"

MQTT_PORT = 1883

MQTT_TOPIC = "vehicle/data"

client = mqtt.Client()

client.connect(MQTT_BROKER, MQTT_PORT, 60)

def get_obd_data():

    rpm = obd_connection.query(obd.commands.RPM)

    speed = obd_connection.query(obd.commands.SPEED)

    coolant_temp = obd_connection.query(obd.commands.COOLANT_TEMP)

    throttle_pos = obd_connection.query(obd.commands.THROTTLE_POS)

    intake_temp = obd_connection.query(obd.commands.INTAKE_TEMP)

    maf = obd_connection.query(obd.commands.MAF)

    return {

        'rpm': rpm.value.magnitude if rpm.value else None,

        'speed': speed.value.to("mph").magnitude if speed.value else None,

        'coolant_temp': coolant_temp.value.magnitude if coolant_temp.value else None,

        'throttle_position': throttle_pos.value.magnitude if throttle_pos.value else None,

        'intake_temp': intake_temp.value.magnitude if intake_temp.value else None,

        'maf': maf.value.magnitude if maf.value else None

    }

def get_gps_data():

    gps_packet = gpsd.get_current()

    return {

        'latitude': gps_packet.lat,

        'longitude': gps_packet.lon,

        'speed': gps_packet.hspeed

    }

def main(sleep_duration):

    while True:

        obd_data = get_obd_data()

        gps_data = get_gps_data()

        # Combine data

        combined_data = {

            'obd': obd_data,

            'gps': gps_data,

            'timestamp': time.time()

        }

        # Log data to console

        print(json.dumps(combined_data, indent=4))

        # Send data to MQTT broker

        client.publish(MQTT_TOPIC, json.dumps(combined_data))

        # Wait before next read

        time.sleep(sleep_duration)

if __name__ == "__main__":

    if len(sys.argv) != 2:

        print("Usage: python script.py <sleep_duration>")

        sys.exit(1)

    sleep_duration = int(sys.argv[1])

    main(sleep_duration)

https://python-obd.readthedocs.io/en/latest/Command%20Tables/

https://github.com/tzebrowski/ObdMetrics