wiki:v2:python
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| - | **!!This page is under construction!!** | ||
| - | |||
| ====== Pixy2 Python tutorial ====== | ====== Pixy2 Python tutorial ====== | ||
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| In this tutorial we will describe the following platforms: | In this tutorial we will describe the following platforms: | ||
| - | * Raspberry Pi: using USB and the libpixyusb2 library. | ||
| * LEGO Mindstorms EV3 using Python on the ev3dev operating system. | * LEGO Mindstorms EV3 using Python on the ev3dev operating system. | ||
| * LEGO Mindstorms EV3 using MicroPython with PyBricks. | * LEGO Mindstorms EV3 using MicroPython with PyBricks. | ||
| + | * Raspberry Pi: using USB and the libpixyusb2 library. | ||
| This tutorial belongs to Pixy2 and Pixy2.1. If you own the previous Pixy, go | This tutorial belongs to Pixy2 and Pixy2.1. If you own the previous Pixy, go | ||
| to the chapter "Pixy for LEGO Mindstorms" in the tutorial | to the chapter "Pixy for LEGO Mindstorms" in the tutorial | ||
| - | [[https://github.com/KWSmit/Pixy_ev3dev|over here]]. That tutorial is written | + | [[https://github.com/KWSmit/Pixy_ev3dev|over here]], written |
| - | by one of our customers. | + | by one of our customers which explains how to use Pixy on LEGO Mindstorms EV3. |
| - | + | ||
| - | ===== Rasberry Pi ===== | + | |
| - | + | ||
| - | <Work in progress> | + | |
| ===== LEGO Mindstorms EV3 ===== | ===== LEGO Mindstorms EV3 ===== | ||
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| page. | page. | ||
| - | ==== API ==== | + | ==== pixycamev3 ==== |
| To make programming more easy for you, we developed a Python API to use Pixy2 | To make programming more easy for you, we developed a Python API to use Pixy2 | ||
| - | on the EV3. The same API can be used with both Python3 and MicroPython. The | + | on the EV3. To use this API you have to install module ''pixycamev3''. |
| + | The same API can be used with both Python3 and MicroPython. The | ||
| only difference is the way you install the API. When installed, using our | only difference is the way you install the API. When installed, using our | ||
| API with Python3 is exactly the same as with MicroPython. But first you have | API with Python3 is exactly the same as with MicroPython. But first you have | ||
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| PixyMon and detach Pixy2 from your computer. | PixyMon and detach Pixy2 from your computer. | ||
| - | ==== Installing Python API ==== | + | ==== Installing pixycamev3 ==== |
| - | This Python API works both with Python3 and MicroPython. | + | This Python API works both with Python3 and MicroPython. There are two ways |
| + | you can walk to use the API: | ||
| - | <TODO: explain how to add python file with API to the project or how to | + | === 1. Installing with ''pip'' === |
| - | install the API with ''pip''. In case of installing with ''pip'' explain how | + | |
| - | to install for Python3 and MicroPython> | + | |
| - | ==== Using Python API ==== | + | > At the moment this method only works for Python3. |
| + | |||
| + | First login to your EV3 using ''ssh''. Run the following command | ||
| + | in a terminal window on your computer: | ||
| + | |||
| + | <code> | ||
| + | $ ssh [email protected] | ||
| + | </code> | ||
| + | |||
| + | where ''robot'' is the default username in ev3dev and ''xxx.xxx.xxx.xxx'' | ||
| + | is the IP-address of your EV3. You will be asked for a password. The default | ||
| + | password is ''maker''. Be sure to use you're own combination of username and | ||
| + | password if you changed the default in ev3dev. | ||
| + | |||
| + | When logged in to EV3, you can install the API package on your EV3 with: | ||
| + | |||
| + | <code> | ||
| + | $ python3 -m pip install pixycamev3 | ||
| + | </code> | ||
| + | |||
| + | This takes about four minutes on the EV3. ''pip'' is not installed | ||
| + | out-of-the-box on ev3dev. You can install ''pip'' with: | ||
| + | |||
| + | <code> | ||
| + | $ sudo apt install python3-pip | ||
| + | </code> | ||
| + | |||
| + | Beware this takes about 18 minutes on the EV3! But you can use | ||
| + | ''pip'' later on to install other python packages when needed. | ||
| + | |||
| + | When package ''pixycamev3'' is installed you're ready to program! Go | ||
| + | to the next paragraph [[#Using Python API|Using Python API]]. | ||
| + | |||
| + | === 2. Adding the API to your project folder === | ||
| + | |||
| + | This method works for both Python3 and MicroPython. | ||
| + | |||
| + | In your project folder create a new folder ''pixycamev3''. Visit the repository | ||
| + | on [[https://github.com/charmedlabs/pixycamev3/tree/main/pixycamev3|Github]]. | ||
| + | Add the file pixy2.py to your folder ''pixycamev3''. The easiest way is to open | ||
| + | this file in Github and click on the ''Raw'' button right above the code window. | ||
| + | Then select all text of the file and copy it to a new file named ''pixy2.py'' | ||
| + | in your ''pixycamev3'' folder. | ||
| + | |||
| + | Your project folder structure should look like this: | ||
| + | |||
| + | <code> | ||
| + | project | ||
| + | ├── pixycamev3 | ||
| + | │ └── pixy2.py | ||
| + | └── main.py | ||
| + | </code> | ||
| + | |||
| + | The file ''pixy2.py'' works for both Python and MicroPython. When you copied | ||
| + | the file you're ready to program! | ||
| + | |||
| + | ==== Using pixycamev3 ==== | ||
| The main object you will need is the ''Pixy2'' class. This object contains all | The main object you will need is the ''Pixy2'' class. This object contains all | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| pixy2 = Pixy2(port=1, i2c_address=0x54) | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| - | prixy2 = Pixy2(port=1, i2c_address=0x54) | + | pixy2 = Pixy2(port=1, i2c_address=0x54) |
| # Get version | # Get version | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| - | prixy2 = Pixy2(port=1, i2c_address=0x54) | + | pixy2 = Pixy2(port=1, i2c_address=0x54) |
| # Get frame resolution | # Get frame resolution | ||
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| | <code> | | <code> | ||
| from time import sleep | from time import sleep | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| - | prixy2 = Pixy2(port=1, i2c_address=0x54) | + | pixy2 = Pixy2(port=1, i2c_address=0x54) |
| # Turn upper leds on for 2 seconds, then turn off | # Turn upper leds on for 2 seconds, then turn off | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2, Pixy2Mode | + | from pixycamev3.pixy2 import Pixy2, Pixy2Mode |
| pixy2 = Pixy2(port=1, i2c_address=0x54) | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| pixy2 = Pixy2(port=1, i2c_address=0x54) | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
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| | MainFeatures object: ^^ | | MainFeatures object: ^^ | ||
| | error | Data error when value True | | | error | Data error when value True | | ||
| - | | length_of_payload | Number of bytes in payload | | + | | %%length_of_payload%% | Number of bytes in payload | |
| - | | number_of_vectors | Number of vectors detected | | + | | %%number_of_vectors%% | Number of vectors detected | |
| - | | number_of_intersections | Number of intersections detected | | + | | %%number_of_intersections%% | Number of intersections detected | |
| - | | number_of_barcodes | Number of barcodes detected | | + | | %%number_of_barcodes%% | Number of barcodes detected | |
| | vectors | List with Vector objects (length number_of_vectors) | | | vectors | List with Vector objects (length number_of_vectors) | | ||
| | intersections | List with Intersection objects (length number_of_intersections) | | | intersections | List with Intersection objects (length number_of_intersections) | | ||
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| | y1 | Y location endpoint vector | | | y1 | Y location endpoint vector | | ||
| | index | Index of vector in array | | | index | Index of vector in array | | ||
| - | | flags | <TODO: ??> | | + | | flags | Internal state, used for testing/debugging | |
| | ^^ | | ^^ | ||
| | Intersection object: ^^ | | Intersection object: ^^ | ||
| | x | X location of intersection | | | x | X location of intersection | | ||
| | y | Y location of intersection | | | y | Y location of intersection | | ||
| - | | nr_of_branches | Number of branches starting at this intersection | | + | | %%nr_of_branches%% | Number of branches starting at this intersection | |
| | branches | Array with Branch objects (length number_of_branches) | | | branches | Array with Branch objects (length number_of_branches) | | ||
| | ^^ | | ^^ | ||
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| | x | X location center of barcode | | | x | X location center of barcode | | ||
| | y | Y location center of barcode | | | y | Y location center of barcode | | ||
| - | | flags | <TODO: ??> | | + | | flags | Internal state, used for testing/debugging | |
| | code | Number of barcode (see Pixy2 wiki) | | | code | Number of barcode (see Pixy2 wiki) | | ||
| | ^^ | | ^^ | ||
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| | **Example:** ^^ | | **Example:** ^^ | ||
| | <code> | | <code> | ||
| - | from pixy2 import Pixy2 | + | from pixycamev3.pixy2 import Pixy2 |
| + | |||
| + | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
| # Detect barcodes and print their number | # Detect barcodes and print their number | ||
| Line 285: | Line 337: | ||
| for i in range(0, data.number_of_barcodes) | for i in range(0, data.number_of_barcodes) | ||
| print('Barcode number: ', data.barcodes[i].code) | print('Barcode number: ', data.barcodes[i].code) | ||
| + | </code> ^^ | ||
| + | |||
| + | ^ %%set_next_turn(angle)%% ^^ | ||
| + | | **Description:** ^^ | ||
| + | | Set direction for turn at the next intersection. After this intersection ^^ | ||
| + | | Pixy2 will choose it's default turn again. ^^ | ||
| + | | **Parameters:** ^^ | ||
| + | | angle | Direction to choose at the next intersection (-180, 180 degrees) | | ||
| + | | **Returns:** ^^ | ||
| + | | None ^^ | ||
| + | | **Example:** ^^ | ||
| + | | <code> | ||
| + | from time import sleep | ||
| + | from pixycamev3.pixy2 import Pixy2 | ||
| + | |||
| + | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
| + | |||
| + | # Set next turn to 90 degrees | ||
| + | pixy2.set_next_turn(90) | ||
| + | </code> ^^ | ||
| + | |||
| + | ^ %%set_default_turn(angle)%% ^^ | ||
| + | | **Description:** ^^ | ||
| + | | Set default direction for all intersections. ^^ | ||
| + | | **Parameters:** ^^ | ||
| + | | angle | Default direction (-180, 180 degrees) | | ||
| + | | **Returns:** ^^ | ||
| + | | None ^^ | ||
| + | | **Example:** ^^ | ||
| + | | <code> | ||
| + | from time import sleep | ||
| + | from pixycamev3.pixy2 import Pixy2 | ||
| + | |||
| + | pixy2 = Pixy2(port=1, i2c_address=0x54) | ||
| + | |||
| + | # Set default turn to 0 degrees (straight on) | ||
| + | pixy2.set_default_turn(0) | ||
| </code> ^^ | </code> ^^ | ||
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| You'll find more practical sample code in the | You'll find more practical sample code in the | ||
| [[https://github.com/charmedlabs/pixycamev3|Github repository]]. | [[https://github.com/charmedlabs/pixycamev3|Github repository]]. | ||
| + | |||
| + | ===== Rasberry Pi ===== | ||
| + | |||
| + | <Work in progress> | ||
wiki/v2/python.1638712737.txt.gz · Last modified: 2021/12/05 13:58 by kees
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