can select bus 1 or 3

python/ina219_both_bus.py

@@ -0,0 +1,62 @@
+"""Sample code and test for adafruit_in219"""
+
+import time
+import board
+import busio
+import smbus
+#from adafruit_blinka.microcontroller.bcm283x import pin
+from adafruit_extended_bus import ExtendedI2C as I2C
+
+from adafruit_ina219 import ADCResolution, BusVoltageRange, INA219
+
+i2c_bus2  = smbus.SMBus(3) # 3 
+b1 = i2c_bus2.read_i2c_block_data(0x45, 0x01, 2)
+print (b1)
+
+#p = busio.I2C(scl, sda)
+#p = busio.I2C(pin.D1,pin.D0)
+#p = board.I2C(pin.D1,pin.D0)
+#p.deinit()
+
+# Create library object using our Extended Bus I2C port
+i2c_bus = I2C(3) # 1 Device is /dev/i2c-1
+
+
+#i2c_bus = board.I2C()
+#i2c_bus = p
+
+print(i2c_bus)
+
+ina219 = INA219(i2c_bus, 0x45)
+
+print("ina219 test")
+
+# display some of the advanced field (just to test)
+print("Config register:")
+print("  bus_voltage_range:    0x%1X" % ina219.bus_voltage_range)
+print("  gain:                 0x%1X" % ina219.gain)
+print("  bus_adc_resolution:   0x%1X" % ina219.bus_adc_resolution)
+print("  shunt_adc_resolution: 0x%1X" % ina219.shunt_adc_resolution)
+print("  mode:                 0x%1X" % ina219.mode)
+print("")
+
+# optional : change configuration to use 32 samples averaging for both bus voltage and shunt voltage
+ina219.bus_adc_resolution = ADCResolution.ADCRES_12BIT_32S
+ina219.shunt_adc_resolution = ADCResolution.ADCRES_12BIT_32S
+# optional : change voltage range to 16V
+ina219.bus_voltage_range = BusVoltageRange.RANGE_16V
+
+# measure and display loop
+while True:
+    bus_voltage = ina219.bus_voltage  # voltage on V- (load side)
+    shunt_voltage = ina219.shunt_voltage  # voltage between V+ and V- across the shunt
+    current = ina219.current  # current in mA
+
+    # INA219 measure bus voltage on the load side. So PSU voltage = bus_voltage + shunt_voltage
+    print("PSU Voltage:   {:6.3f} V".format(bus_voltage + shunt_voltage))
+    print("Shunt Voltage: {:9.6f} V".format(shunt_voltage))
+    print("Load Voltage:  {:6.3f} V".format(bus_voltage))
+    print("Current:       {:9.6f} A".format(current / 1000))
+    print("")
+
+    time.sleep(2)