maksoltane / esp32_xiaomi_m365

Sample Project for decoding serial bus data on a Xiaomi M365 Scooter on Espressif ESP32 / ESP8266

esp32_xiaomi_m365

Sample Project for decoding serial bus data on a Xiaomi M365 Scooter on Espressif ESP32 / ESP8266:

• Cheap 128x64 pix OLED SSD1306 based
• ESP32/Arduino Code
• ESP8266/Arduino works as well, right now no ESP32-specific features are used (might come later)
• OTA for Firmwareupdates
• Telnet Screens for debugging
• Oled Display with different Screens in Drive/Charge/Stop Mode
• use Throttle in stopped mode to Swipe through different screens

Done

• WiFi Auto Connect to known SSIDs or AP-Mode & Telnet with Timeouts to auto-turnoff Telnet/WiFi
• Firmwareupdates (of ESP Device, not the scooter) over WiFi
• Telnet on Port 36523 with different Screens
• Telnet on Port 36524 with raw byte dump from M365 Bus ("read only")
• M365 Serial Receiver and Packet decoder into Array per Address
• Decoder of BMS Data Array to Variable Values/Telemetrie Screen verified against known apps
• Decoder of ESC Data Array to Variable Values/Telemetrie Screen verified against known apps
• Data Requestor
• Subscription to interesting data fields needed for client-app (e.g. OLED Display)
• Basic screens (nicer layout to follow) for drive/stall/charging
• Added Loop-Timers and Counters for debugging Receiver/Requestor & Oled-Draw/Transfer Durations
• OLED Shows LED/Light Status (to recognize accidental switched on Light @ noon while switching normal/eco mode)
• added handling of 2nd OLED screen, used library has some problems with it -> disabled
• added ESP32 Status Screen
• reformated driving-screen
• status screen for ota-firmwareupdate
• added boilerplate screen in stop mode
• fixed display lock by wlan-search
• added charge subscreen with cell voltages
• Telnet on Port 36525 with packet decode/dump from M365 Bus ("read only")
• compiles on ESP8266, UART/Statemachines/OLED untestet on this plattform
• verified function on ESP8266

Todos

• fix - data-requestor timing currently causes ~10% crc errors on m365 bus
• OLED: Add Popup Messages for Events (e.g. Scooter Error, Temp, BMS CellVoltage variations > treshold, WLAN/BLE On/Off, Client Connected,...)
• Add Menu/Change functionality for "Config" Screen Items
• Add Background housekeeper task
  • Check Scooter Error Register
  • Firmware-Flash Protection
  • Alert User if Cell-Voltages difference is above a treshold
• custom PCB with 2 OLEDs, ESP32S, VReg and touch areas
• add sleeptimer - x seconds after last event (gas/brake/throttle/speed/chargerun-plug/telnet/AP-Client Connection) - stop sending requests, so scooter can timeout/turn itself off
• advanced thief/lock protection

further Ideas & Visions:

• add Scooter-Flashing Protection (so no one can flash broken firmware to your scooter while waiting at a red traffic light
• advanced trip computer (which keeps trip-totals/averages between 2 charge cycles or 2 times with the same available SSID (leaving/coming home)
• MQTT Logging of Trip-Summary Data
• Navigation Arrow Display e.g. with Komoot (https://github.com/komoot/BLEConnect)

Telnet Interface

• Telemetrie Screen shows decoded known values: Batt Voltage, Current, Speed,...
• Statistics Screen dumps some internal counters, e.g. Packet Counters, CRC Files, Timing,...
• ESC/BLE/BMS/"X1" RAW Screens dumps the 512 Byte Array for each device (format "00 00 ...")
• ESC/BLE/BMS/"X1" Array Screens dumps the 512 Byte Array for each device (in copy & paste format "const bledata[512]={0,0,0...};")

use the letters

• s,t,e,b,n,x,E,B,N,X to switch between the screens
• r to reset statistics & m365 data arrays

Wiring

M365 has a Serial One Wire Bus between BLE Module and ESC which consists of 4 wires, the connection as seen on the BLE Module:

• Ground (Black, "G")
• One Wire Serial Connection (Yellow, "T", 115200bps, 8n1)
• VBatt (Green, "P", always available)
• 5V (Red, "5", only when scooter is turned on)

ESP32/8266 needs a Vcc of 3.3V, while at the same time the GPIO Pins are 5V save, so you can wire the 5V to a Vreg for 3.3v which feed the ESP, while the Serial Connection can be wired to RX/TX Pins. It might be a idea to use e.g. 680R or 1k in series to protect the gpio, as well as add a diode from rx in series with a ~100-200R towards TX

Hints

As there's some hicups with the standard arduino libraries (and the adafruit ssd1306 oled lib) and their implementation on the esp32, some changes need to be made to the source of arduino-esp32 core and adafruit-ssd1306 library -> see comments in the source.