请注意，本文内容源自机器翻译，可能存在语法或其它翻译错误，仅供参考。如需获取准确内容，请参阅链接中的英语原文或自行翻译。
器件型号：BQ27441-G1 工具与软件：
您好！
我一直在使用 BQ27441来开发嵌入式项目。 我已经把它做得很好的工作,但我不会写新的能力。 我已经测试过芯片、读取的电压、温度、电流都正确、这是预期结果。 我在 Python 中编写此代码、但当我读取容量时、它仍读取为默认值。
当我设置电池容量时、我执行以下操作：
解封
进入扩展模式
写入寄存器以获取电池容量
退出扩展模式
密封
这不会产生任何错误、器件可以工作并向我提供读数、但容量尚未更新。 我随附了此示例的完整代码、以防将来有人在 Raspberry PI 或其他 Linux 发行版的入门方面需要任何帮助。
import smbus2
import time
# I2C address of BQ27441
BQ27441_I2C_ADDR = 0x55
# Register addresses
CONTROL_REG = 0x00 # Control register
EXTENDED_DATA_CTRL = 0x3E # Extended Data Control register
DESIGN_CAP_REG = 0x4B # Design Capacity register
EXIT_CFGUPDATE_REG = 0x44 # Exit Config Mode
SOC_REG = 0x1C # State of Charge register
VOLTAGE_REG = 0x04 # Battery Voltage register
CURRENT_REG = 0x10 # Average Current register
TEMP_REG = 0x02 # Battery Temperature register
REMAINING_CAP_REG = 0x0A # Remaining Capacity register
SOH_Reg = 0x20 #State of health
# Control Subcommands
UNSEAL_KEY_1 = 0x8000
SEAL_COMMAND = 0x0020
ENTER_CFGUPDATE = 0x0013
# Battery capacity to set (mAh)
BATTERY_CAPACITY = 4500
# Initialize I2C bus
bus = smbus2.SMBus(1)
def write_register(reg, value):
"""Writes a 16-bit value to the specified BQ27441 register."""
data = [value & 0xFF, (value >> 8) & 0xFF] # Low byte first
bus.write_i2c_block_data(BQ27441_I2C_ADDR, reg, data)
def read_register(reg):
"""Reads a 16-bit value from the specified BQ27441 register."""
data = bus.read_i2c_block_data(BQ27441_I2C_ADDR, reg, 2)
return data[0] | (data[1] << 8)
def unseal_battery():
"""Unseals the BQ27441 to allow writing to protected registers."""
write_register(CONTROL_REG, UNSEAL_KEY_1)
time.sleep(0.1)
def seal_battery():
"""Seals the BQ27441 to protect configuration settings."""
write_register(CONTROL_REG, SEAL_COMMAND)
time.sleep(0.1)
def enter_extended_mode():
"""Enables Extended Mode for configuration changes."""
write_register(CONTROL_REG, ENTER_CFGUPDATE) # Enter Config Mode
time.sleep(0.1)
def exit_extended_mode():
"""Exits Extended Mode and applies changes."""
write_register(EXIT_CFGUPDATE_REG, 0x00) # Exit Extended Mode
time.sleep(0.1)
def set_battery_capacity(capacity):
"""Sets the battery capacity in Extended Mode."""
unseal_battery() # Unseal before modifying protected settings
enter_extended_mode()
# Access Design Capacity Block
write_register(EXTENDED_DATA_CTRL, 0x13)
time.sleep(0.1)
# Write new battery capacity
write_register(DESIGN_CAP_REG, capacity)
time.sleep(0.1)
exit_extended_mode()
seal_battery() # Reseal after configuration
return read_register(DESIGN_CAP_REG) == capacity
def get_battery_percentage():
"""Reads the battery's state of charge (SOC) in percentage."""
return read_register(SOC_REG)
def get_battery_voltage():
"""Reads the battery voltage in millivolts (mV)."""
return read_register(VOLTAGE_REG)
def get_current_draw():
"""Reads the battery current draw in mA (negative = discharge, positive = charge)."""
raw_current = read_register(CURRENT_REG)
if raw_current > 32767: # Convert two's complement for negative values
raw_current -= 65536
return raw_current
def get_battery_temperature():
"""Reads the battery temperature in Celsius."""
raw_temp = read_register(TEMP_REG) # Temperature in 0.1 Kelvin
temp_celsius = (raw_temp / 10.0) - 273.15 # Convert to Celsius
return round(temp_celsius, 2)
def get_remaining_capacity():
"""Reads the remaining battery capacity in mAh."""
return read_register(REMAINING_CAP_REG)
def get_state_of_health():
"""Reads state of battery"""
soh_data = read_register(SOH_Reg)
return soh_data & 0xFF
# Main execution
if __name__ == "__main__":
print("Initializing BQ27441...")
if set_battery_capacity(BATTERY_CAPACITY):
print(f"Battery capacity set to {BATTERY_CAPACITY} mAh")
else:
print("Failed to set battery capacity!")
while True:
battery_percentage = get_battery_percentage()
battery_voltage = get_battery_voltage()
current_draw = get_current_draw()
battery_temperature = get_battery_temperature()
remaining_capacity = get_remaining_capacity()
state_of_health = get_state_of_health()
print(f"Battery Percentage: {battery_percentage}%")
print(f"Battery Voltage: {battery_voltage} mV")
print(f"Current Draw: {current_draw} mA")
print(f"Battery Temperature: {battery_temperature}°C")
print(f"Remaining Capacity: {remaining_capacity} mAh")
print(f"State of Health: {state_of_health}")
print("-" * 40)
time.sleep(2) # Delay before next reading
