A WEB Based or Wifi/BLE (ELM327 Compatible) OBDII Dongle Platform using the ESP32 WROVER (16MB) Module
An OBDII Dongle using the ESP32 Wrover with built-in SPIFFF memory is used as a CAN BUS OBDII reader and the data is presented as web page using a built-in webserver. The webpage code communicates to the dongle via WiFi and uses websockets to retrieve OBDII data. The platform is using an ESP32 microcontroller which is a dual core mcu with the first core handling the CAN Bus comunications part via SN65HVD230 CAN BUS Transceiver and the 2nd core handling the websocket part. OBDII data is pushed to the UI every 60ms to 100ms for critical data such as rpm and speed, and every 1000ms for not so critical data such as temp, voltage, etc.
The platform code is using ESP32 RTOS for the multi core multi tasking component. That's basically an OBDII with a webserver running inside that dongle attached to the car's obd port. And literally you can read every car metric data and show it on the car infotainment / Web browser / Phone app with customizable fancy UI stuff (gauges, graphs, etc.) using standard HTML/JS/CSS/JPG renders.
Mobile phone apps not required as long as the infotainment/mobilephone/etc can render the UI using a standard web browser.
Once the UI client is connected to the ESP32 via WIFI, the dongle webserver can be accessed via these urls:
OBD HomePage:
ESP32 Load Monitoring:
http://192.168.0.10/page?var=file&val=/ui/CPULoad/index.html
WEB ASSETS are stored in the ESP32 SPIFFS memory storage which is automatically populated one time from the data on the SD Card. A SPIFF memory update is triggred by deleting the lock.file on the SD card. Any updates on the WEBSERVER files should be done on the SD card with the "lock.file" deleted.
There are two BLE modules used for this project. The first BLE/Bluetooth Module built in with the ESP32 is used as the Bluetooth connector for the OBDII dongle and can be used to to connect to Mobile OBDII apps such as TORQUE.
The 2nd Bluetooth/BLE module a JDY-08 contains a user programmable CC2541 BLE Chipset which can be used to receive Car sensor data that are bluetooth based. DEMO CC2541 codes are provided to receive BLE Advertisments from TPMS Sensors such as the Bluetooth based VC601 Tire Pressure Sensors or a Battery Monitoring Sensor (BM2). The same BLE module can be loaded with a UART-BLE for ELM327 AT command compatible communication.
EQM_OBDWEB uses the SD Card as temporary storage. The WEB DOCROOT files are loaded to the ESP32 Wrover SPIFFs memory for faster page load time. It also utilizes the PSRAM as a temporary buffer for SPIFFs loading up to HTTP delivery. SPIFFS file storage is initially formatted and populated with contents coming from the SD-Card. This is automatically done once the code detects if the SD-Card doesnt have the 'lock.file' inside. It copies the content of the SD-Card to the SPIFFs storage and then creates a 'lock.file' on the SD-card to prevent succeeding SPIFFS formatting and file copy.
Here is the Connection diagram of the ESP32 Wrover with SD Card Reader and JDY08 BLE Module
Here is the suggested development platform (codes included) which provides the user options flash code on the ESP32 Wrover and to burn firmware on the CC2541 by simply dropping a cc2541.bin file on the SD card. The EQM_OBDWEB dongle contain codes to flash the CC2541 JDY-08 module. Another option is by flashing the Wrover with a CCloader arduino code and connecting it to a laptop then uploadthe cc2541 firmware using the ccloader windows program.
Using a separate ARDUINO Board and sketch to burn firmware on the JDY-08 Module using the CCLoader Program
https://github.com/EQMOD/EQM_OBDWEB/tree/master/CC254x_TPMS_BATMON/JDY08_CCLoader
Current firmware codes are stable with ESP32 Version 2.0.5 up to 2.0.12. Seems to be encountering issues on 2.0.13 and 2.0.14 particularly on the Wifi and SD Card handlers. This using the ESP32 Wrover (16MB) as the code utilizes the SD Card, the SPIFFS Memory, and the PSRAM.
USER CUSTOMIZABLE WEB PAGES FOR CAR DASHBOARDS OR OTHER CAR METRICS DATA USING HTML/CSS/JS/IMG with live data using websockets. Just load your designs to the SD Card:
https://github.com/EQMOD/EQM_OBDWEB/tree/master/Custom_USERS_WEBUI/Sample_SPDO
A sample WEBPAGE with a LIVE video camera/webcam FEED element as the background with the OBDII/ESP32 data (text, needle , bars, charts) on the foreground
https://github.com/EQMOD/EQM_OBDWEB/tree/main/Custom_USERS_WEBUI/WebCAM_and%20WebSocket_Only
It is also possible to provide OBD-II data on top of a Mobile or Tablet camera live feed using the phone's browser ONLY if the webpage with your esp32 embedded data is hosted as localhost or as a direct filesystem html page load or a page loaded via https with a valid SSL certificate. For this demo , all html/css/js/img (files on the above link) are loaded via localhost webserver(using KSWeb app) running on an Android phone. The js part of the page is the one responsible of fetching the esp32 data via websockets and rendering it on top of the phonecam video feed
Using the original gauge assets and replacing the background images with a live feed of phonecam video. The approach is the same as what was described on the previous section. Here is another demo of a mobile phone web browser with the phonecam live feed rendering on the background and the gauge assets rendering on the chrome browser foreground. Rendered using chrome browser html/js/css/img with the JavaScript communicating to the esp32 obdii using websockets. Obdii dongle is acting as a wifi hotspot while connected to the car's OBD Port. I used jQuery and charts.js for the gauge renders. Upper left corner shows a live load stats of the ESP32 dual cores.
Webpage Code and Assets:
https://github.com/EQMOD/EQM_OBDWEB/tree/main/Custom_USERS_WEBUI/OBDGauges_WEBCam_Websockets
How to flash the esp32 itself ;
Using an "ESP32 Downloader"
TPMS VC601 Broadcast emulator for testing the cc2541 codes uing a CCDebugger
JDY08 Firmware source codes to receive BLE VC601 TPMS Sensor broadcasts and presented to the ESP32 via UART
This version of the program works best with a ESP32-D0WD-V3 (revision 3) 16MB with the following compile settings;
- Board: "ESP Wrover Module"
- Upload Speed: "921600"
- Flash Frequency: "80MHz"
- Flash Mode: "QIO"
- Partition Scheme: "Default 4MB with spiffs (1.2MB APP/1.5MB SPIFFS)"
- Core Debug Level: "None"
- Erase All Flash Before Sketch Upload: "Disabled"
Formatting and flashing the SPIFF Memory is initiated by checking if a detected/attached SD Card doesn't have a "lock.file" inside;
A portable flasher and serial Console Monitoring port in one is implemented on the EQM_OBDWEB Dongle. The idea here is we use the same 6 pin port to flash new code on the ESP32 inside the obd dongle OR use it as Serial Console port by plugging in a JDY-16 Bluetooth UART module and connect it to a mobile app BLE Serial Terminal and monitor the ESP32 activity through a mobile phone;
Flasher and JDY-16 modules both fit on the same flashing port on the EQM_OBDWEB Dongle:
Multiple esp32 dongles are used with one acting as an ECU Emulator.
The development / debugging can be done using multiple instances of the OBD ESP32 Dongles - One with loaded code functioning as an OBDII-Simulator (code included in the repository), A Dummy OBD--II Node (To simulate CAN BUS Traffic) and the EQM_OBDWEB ESP32 OBDII Dongle. The Dummy OBDII CAN Bus node is just the same code as the EQM_OBDWEB with a different WIFI/BLE name and it doesn't wait for CAN BUS Activity. The EQM_OBDWEB waits for CAN BUS Activity specifically to put it in SLEEP MODE (Power Management). This one needs more improvement as we are still trying to find options to lessen the the power consumption if in case we decide to leave the dongle attached to the OBDII port of the car....
...and YES!! You can technically use any ESP32 Board such as a ESP32-CAM as an OBDII Dongle (but you need to check the memory specs)
Here is one example of an ESP32-CAM Board used as an OBD-II Emulator and its flashing LED as an indicator for CAN BUS Activity :-D
