Python Library for ECU-P hardware
Getting Started
This guide will help you setup Python to control memetis ECU-P hardware.
Install VCP driver
The ECU-P hardware uses chip from SiliconLabs for the communication over USB. Unfortunatly this requires installation of a driver package from the chip vendor.
Visit SiLabs Download page and switch to Downloads tab. Download the current version for macOS.
Unzip the downloaded file, mount SiLabsUSBDriverDisk.dmg by double-clicking it and run Install CP210x VCP Driver.app.
Follow the installation instructions. You will be prompted to enter your password twice. After a short while you will be informed that a system extension was blocked.
Open the Security & Privacy pane in macOS Settings.
Allow making changes by clicking the small lock symbol in the bottom right-hand corner. Then allow the CP210xVCPDriver.app.
The installation will finish automatically.
Visit SiLabs Download page and switch to Downloads tab. Download the current version for Windows.
Unzip the downloaded file and open the folder.
Right-click on silabser.inf, select Show more options and hit Install.
You will be asked to allow to make changes to your device. Select Yes.
The installation will complete without any further notifications.
The VCP driver has been integrated in the Linux kernel since version 3.
Note
The user running Python needs access to serial devices. On most Linux distributions this is achieved by adding the user to the dialout group.
Use this command to add your username to this group:
sudo usermod -a -G dialout your_username
Check USB connection
Before continuing you can use the steps below to check if the driver was successfully installed and the ECU-P hardware is found by your computer.
Connect the ECU-P hardware with a USB micro cable to your computer.
Open the Terminal application.
Run
ls -l /dev/cu.*in the terminal.You should see at least two devices. /dev/cu.SLAB_USBtoUART & /dev/cu.usbserial-110 in addition to devices already present on your system.
Note
If you cannot see the ECU-P hardware /dev/cu.SLAB_USBtoUART try updating the VCP driver from the previous step. Make sure you allowed the system extension under Security & Privacy.
You can also try with a different USB cable.
Connect the ECU-P hardware with a USB micro cable to your computer.
Open Device Manager to see all connected hardware.
Expand the Ports (COM & LPT) section.
You should see a device called Silicon Labs CP210x USB to UART Bridge and the serial interface name in brackets.
Note
If you cannot see the ECU-P hardware try updating the VCP driver from the previous step.
You can also try with a different USB cable.
Connect the ECU-P hardware with a USB micro cable to your computer.
Open a terminal. In Ubuntu it’s called Terminal.
Run
ls -l /dev/ttyUSB*in the terminal.You should see at least one device named /dev/ttyUSB0.
Note
Depending on your distrubution serial devices might be named differently. You can check with ls -l /dev/tty* to see all available serial port.
You can also try with a different USB cable.
Install and check Python
The ECU-P library requires Python 3.7 or higher.
macOS comes with Python 3 pre-installed. Its available with the python3 and pip3 commands.
Check that the version is at least 3.7 and that pip is working. Run the following two commands in Terminal:
python3 --version
pip3 --version
These commands should not generate any error messages and display the version number of Python 3 and the package manager pip.
Windows does not come with Python pre-installed. You need to install it using the following steps:
Download Python 3 from python.org. Make sure to select Python 3 and not version 2. Get the Windows installer for you Windows variant (32bit/64bit).
Execute the downloaded Python installer.
Make sure to select Add Python 3.x to PATH and press Install Now.
When asked, allow the installer to make changes to the system.
The installation should complete
Once you have installed Python 3 open the Command Prompt app and enter the following two commands:
python --version pip --version
These commands should not generate any error messages and display the version number of Python 3 and the package manager pip.
Many Linux distributions come with Python pre-installed. If it is not installed you can install it by running sudo apt install python3 python3-pip in your terminal.
Check that the version is at least 3.7 and that pip is working. Run the following two commands in the terminal:
python3 --version
pip3 --version
These commands should not generate any error messages and display the version number of Python 3 and the package manager pip.
Install ECU-P Python library
Install the ECU-P library by running
pip3 install https://gitlab.com/memetis/ecu-p/python/-/archive/master/python-master.zip
in the terminal / Command Prompt. This will automatically download and install the latest version of the library. You can use the same command to update any old version to the latest one.
Connect to ECU-P hardware with Python
Create a new Python program with the following content:
import logging
from ecu import ECUManager
logging.getLogger().setLevel(logging.WARNING)
logging.warning('Connection example started!')
manager = ECUManager()
for ecu in manager.get_all():
print(ecu)
Run this Python program with ECU-P hardware conencted to your computer with a USB micro cable.
It will test all available serial ports on your computer for ECU-P hardware automatically. It then prints out information (product name, firmware version, serial port and UUID) of all found ECU-P devices.
Note
If no device was found make sure you followd all the above steps. Make espacially sure that your computer recognises the ECU-P hardware as a serial port.
Enable output for 5 seconds
Create a second Python program with the following content:
import logging
import time
from ecu import ECUManager
logging.getLogger().setLevel(logging.INFO)
logging.info('Connection example started!')
manager = ECUManager()
ecu = manager.get_all()[0]
print(ecu)
ecu.enable(1)
time.sleep(5)
ecu.disable(1)
Run this Python program with ECU-P hardware conencted to your computer with a USB micro cable.
It will search all serial ports for ECU-P hardware. It then prints out information about the first found device. Then it enables CH1 output. After waiting 5 seconds it disables the output again.
You should see the LED on the front panel turn on. Depending on the configuration of you device, this LED will turn off automatically after 300 milliseconds (for bistable valves, this can be overwritten by enabling manual_mode) or 5 seconds (for NC valves).