Install the SDP Driver
The driver installation consists of creating a Python virtual environment, activating it, and installing the driver using pip.
Create a Python virtual environment:
python -m venv .venv
Activate the virtual environment:
source .venv/bin/activate
.venv\Scripts\Activate.ps1
.venv\Scripts\activate.bat
Install the driver:
python -m pip install sensirion_i2c_sdp
Use the SensorBridge on Windows
Install the driver for the Sensirion SEK-SensorBridge:
python -m pip install sensirion-shdlc-sensorbridgeConnect the SEK-SensorBridge to your PC over USB.
If the SEK-SensorBridge is not detected by your system, follow the SensorBridge FTDI Driver Installation.
Connect the SDP sensor to the SEK-SensorBridge.
Run an example script in the activated virtual environment.
By default, the script assumes that the SensorBridge is connected to the
COM1serial port. If a different port is used, specify it with the--serial-portparameter:python example_run.py --serial-port <your COM port>
Example script
import time
from sensirion_shdlc_driver import ShdlcSerialPort, ShdlcConnection
from sensirion_shdlc_sensorbridge import SensorBridgePort, \
SensorBridgeShdlcDevice, SensorBridgeI2cProxy
from sensirion_i2c_driver import I2cConnection
from sensirion_i2c_sdp import SdpI2cDevice
# Connect to the SensorBridge with default settings:
# - baudrate: 460800
# - slave address: 0
with ShdlcSerialPort(port='COM1', baudrate=460800) as port:
bridge = SensorBridgeShdlcDevice(ShdlcConnection(port), slave_address=0)
print("SensorBridge SN: {}".format(bridge.get_serial_number()))
# Configure SensorBridge port 1 for SDP
bridge.set_i2c_frequency(SensorBridgePort.ONE, frequency=100e3)
bridge.set_supply_voltage(SensorBridgePort.ONE, voltage=3.3)
bridge.switch_supply_on(SensorBridgePort.ONE)
# Create SDP device
#
# Make sure to use the correct i2c address:
# SDP8xx supports the 0x25 and 0x26 I²C addresses, SDP3x supports the
# 0x21, 0x22 and 0x23 I²C addresses.
# Refer to the dedicated datahseet for more detailed information.
i2c_transceiver = SensorBridgeI2cProxy(bridge, port=SensorBridgePort.ONE)
sdp = SdpI2cDevice(I2cConnection(i2c_transceiver), slave_address=0x25)
sdp.stop_continuous_measurement()
sdp.start_continuous_measurement_with_mass_flow_t_comp()
# Measure
try:
for _ in range(50):
differential_pressure, temperature = sdp.read_measurement()
# use default formatting for printing output:
print("{}, {}".format(differential_pressure, temperature))
# custom printing of attributes:
print("{:0.2f} °C ({} ticks), {:0.2f} Pa ({} ticks)".format(
temperature.degrees_celsius, temperature.ticks,
differential_pressure.pascal, differential_pressure.ticks))
time.sleep(0.2)
finally:
sdp.stop_continuous_measurement()
bridge.switch_supply_off(SensorBridgePort.ONE)