Firmware for the Battery Management System (BMS) developed for RIT's Electric Vehicle Team (EVT).

This project implements a high-level BMS master controller responsible for:

• Monitoring battery health and operating conditions
• Managing communication with battery ICs
• Enforcing safety protections
• Coordinating system-level behavior

Built on top of the EVT-core library for embedded hardware abstraction.

In order for this firmware to work with the EVT-core library the following lines must be changed in manager.hpp

void init() -> inline void init()

RTC& getRTC() -> inline RTC& getRTC()

• docs - Project documentation, diagrams, and reports
• inc - Header files
• src - Source files
• lib - External dependencies (EVT-core)
• tests - Test code and validation utilities
• build - Build output (generated)
• LICENSE

The BMS firmware runs on an STM32 microcontroller and interfaces with multiple devices:

• BQ34Z100-R2 – Fuel Gauge (I2C)
• BQ79600 – SPI Bridge (stack communication)
• BQ79631 – High Voltage Monitor
• M24C32 – EEPROM
• Thermistors – Temperature sensing via ADC
• CAN Transceiver – External communication (planned)

• Measurement acquisition (voltage, current, temperature)
• Safety monitoring and fault handling
• Device communication (I2C, SPI, UART, CAN)
• State machine control

git clone <repo-url>
cd MSD_BMS

Follow setup instructions in:

lib/EVT-core/README.md

This includes

• ARM GCC Toolchain
• CMake configuration
• HAL/CMSIS setup

cmake -B build -DCMAKE_TOOLCHAIN_FILE=lib/EVT-core/cmake/arm-gcc-toolchain.cmake
cmake --build build

This will generate the firmware binary in the build/ directory.

To flash the compiled firmware onto the target STM32 microcontroller, use OpenOCD, STM32CUBE or ST-Link. Ensure the following:

• Correct target selected (STM32F446RE)
• Proper clock configuration
• Stable power supply
• Utilize BMS.cpp for testing

The system performs:

1. Hardware Setup

   • TIM2 configured for microsecond timing
   • GPIO initialized (LEDs, control lines)

2. Communication Interfaces

   • I2C (fuel gauge + EEPROM)
   • SPI (BQ79600 stack)
   • UART (debug)
   • CAN (initialized, not fully used)

3. Device Initialization

   • Fuel gauge (BQ34)
   • EEPROM integrity check (write/read test)
   • BQ79631 monitor setup

4. BQ79600 Bring-Up (Critical)

   • GPIO-based wake sequence (not SPI)
   • SPI communication validation
   • Bridge initialization

5. Sensor Setup

   • Thermistors initialized via ADC

Each update() cycle performs:

1. Measurements

   • Slave Device:
     • need to complete...
   • Fuel gauge:
     • Voltage
     • Current
     • Temperature
     • State of Charge (SOC)
     • Flags
   • High Voltage Monitor:
     • Die temperature
     • Fault flags
     • Pack Voltage
   • Thermistors:
     • Individual readings + average

2. Protection Logic

   • Fault detection via BQ34 flags
   • Warning/fault classification

3. State Machine

   • INIT → NORMAL
   • NORMAL → steady operation
   • WARNING → LED indication
   • FAULT → system halt behavior
   • SHUTDOWN → safe stop

Enabled via:

#define BMS_DEBUG
#define MESSAGE_DEBUG

Heavy UART logging significantly slows execution and should only be used while debugging

If the system is not functioning:

Fuel Gauge (I2C)

• Confirm valid register reads

EEPROM

• Ensure write/read test passes

BQ79600 (SPI)

• Verify wake sequence timing
• Confirm DEV_CONF1 == 0x14

SPI

• Mode = MODE0
• Proper chip select handling

General

• Verify stable voltage rails