電量量測 - INA219直流電流電壓量測

電量量測 - INA219直流電流電壓量測

 電路圖

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Python - ePy-Lite_INA219.py

"""   ePy-Lite_INA219.py     ePy-Lite  INA219  Battery   Pin       Pin   -------------------------             VIN+    BAT+   VIN       VIN-   P16_SDA0  SDA   P17_SCL0  SCL   GND       GND     BAT-   3V3       VCC """   from micropython import const from machine import Switch  #Get button KEY library from machine import Pin, LED, I2C from machine import Timer, RTC import utime import ustruct import sys from htu21d import HTU21D import ssd1306   DEBUG = True KeyADone = None TimerDone = None RTCDone = None today = (2021,9,12,5,6,0,0,0)   I2C_FREQ = 100000 oled_width = 128 oled_height = 64   CONF_Reg        = const(0x00) # Configuration SHUNT_V_Reg     = const(0x01) # Shunt Voltage BUS_V_Reg       = const(0x02) # Bus Voltage POWER_Reg       = const(0x03) # Power CURRENT_Reg     = const(0x04) # Current CALIBRATION_Reg = const(0x05) # Calibration   INA219_address = 0x45 MAX_CURRENT = 3.2 # Amps CURRENT_LSB = MAX_CURRENT/(2**15) R_SHUNT = 0.1 # Ohms   class INA219(object):   def __init__(self, i2c=None,Rsh=0.1,BRNG=1,PG=3,BADC=3,SADC=3,MODE=7, addr=0x40):     # construct an I2C bus     if not i2c:       i2c = I2C(0,I2C.MASTER,baudrate=100000)     #Create I2C0 Master Mode, Baudrate=100kHz     self.i2c = i2c     self.i2c_addr = addr     self.buf = bytearray(2)       self.Rsh = Rsh     config = ((BRNG&0x00)<<13)|((PG&0x03)<<11)|((BADC&0x07)<<7)|((SADC&0x0F)<<3)|(MODE&0x07)     CALIBRATION = int(0.04096 / (CURRENT_LSB * self.Rsh))     self._write_register(CONF_Reg,config)     self._write_register(CALIBRATION_Reg,CALIBRATION)     if(DEBUG):       print('Configuration:0x{:4X}'.format(config))       print('Calibration:0x{:4X}'.format(CALIBRATION))       print(self._read_register(CONF_Reg))       print(self._read_register(CALIBRATION_Reg))     def _write_register(self,reg,value):     self.buf[0] = (value >> 8) & 0xFF     self.buf[1] = value & 0xFF     self.i2c.mem_write(self.buf, self.i2c_addr, reg)     def _read_register(self,reg):     self.buf = self.i2c.mem_read(2, self.i2c_addr, reg & 0xff)     # value = (self.buf[0] << 8) | (self.buf[1])     return self.buf     def read_ShuntVoltage(self):     """The shunt voltage (between V+ and V-) in Volts (so +-.327V)"""     buffer = self._read_register(SHUNT_V_Reg)     value = ustruct.unpack('!h', buffer)[0]     return -value*self.Rsh #100uV/0.1Ω=1mA     def read_Voltage(self):     """The bus voltage (between V- and GND) in Volts"""     buffer = self._read_register(BUS_V_Reg)     value = ustruct.unpack('!h', buffer)[0]     return (value>>3)*4.0 #mV     def read_current(self):     """The shunt voltage (between V+ and V-) in Volts (so +-.327V)"""     buffer = self._read_register(CURRENT_Reg)     value = ustruct.unpack('!h', buffer)[0]     return -value/10     def read_Power(self):     """"""     buffer = self._read_register(POWER_Reg)     value = ustruct.unpack('!h', buffer)[0]     return value*2   def key_int():   global KeyADone   KeyADone = True   def tick3(timer):   global TimerDone   TimerDone = True   def tickRTC(rtc):   global RTCDone   RTCDone = True   # Start Function if __name__ == '__main__':   print(sys.platform)   ledY = LED('ledy')   ledR = LED('ledr')   ledY.off()   ledR.off()     KeyA = Switch('keya')    #Create button A   KeyA.callback(key_int)   KeyADone = False     timer = Timer(3,freq = 5)   timer.callback(tick3)   TimerDone = False     rtc = RTC()   rtc.datetime(today)   rtc.tickcallback(tickRTC)   RTCDone = False     i2c = I2C(0,I2C.MASTER,baudrate=I2C_FREQ)     #Create I2C0 Master Mode, Baudrate=100kHz   oled = ssd1306.SSD1306_I2C(oled_width,oled_height,i2c)   sensor = HTU21D(i2c)     ina = INA219(i2c,R_SHUNT,0,3,3,3,7,INA219_address)   utime.sleep_ms(100)   print("--- Start measurement ---")     while True:     if RTCDone == True:       ledY.toggle()       RTCDone = False       if TimerDone == True:       ledR.on()         Temperature = sensor.readTemperatureData()       Humidity = sensor.readHumidityData()         SVCell = ina.read_ShuntVoltage()    #       VCell = ina.read_Voltage()    # read the voltage of the battery       ICell = ina.read_current()    # read the current of the battery       PCell = ina.read_Power()      # read the Power of the battery         oled.fill(0)       oled.text('INA219/HTU21D',0,0,1)       oled.text('V:{:.1f}mV'.format(VCell),0,10,1)       oled.text('I:{:.1f}mA'.format(ICell),0,20,1)       oled.text('P:{:.1f}mW'.format(PCell),0,30,1)       oled.text('T:{:.1f}C'.format(Temperature),0,40,1)       oled.text('H:{:.1f}%'.format(Humidity),0,50,1)       oled.show()       if(DEBUG):         print('V:{:.1f}mV, I:{:.1f}mA, P:{:.1f}mW'.format(VCell,ICell,PCell))         # print('I:{:.1f}mA'.format(SVCell))         print('Temperature:{:.1f}C,"Humidity:{:.1f}%'.format(Temperature,Humidity))         ledR.off()       TimerDone = False       if KeyADone == True:      #Press A Key       break     # utime.sleep_ms(100)     i2c.deinit() # close the connection to the module   KeyA.callback(None)   timer.callback(None)   timer.deinit()   ledY.off()   print("Exit measurement.")

 

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