This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision Last revision Both sides next revision | ||
wiki:v2:python [2021/12/05 13:58] kees 211205 - Several edits in text |
wiki:v2:python [2021/12/30 13:02] kees Added set_next_turn() and set_default_turn() and removed some typos |
||
---|---|---|---|
Line 1: | Line 1: | ||
- | **!!This page is under construction!!** | ||
- | |||
====== Pixy2 Python tutorial ====== | ====== Pixy2 Python tutorial ====== | ||
Line 17: | Line 15: | ||
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 ===== | ||
Line 82: | Line 76: | ||
==== Installing Python API ==== | ==== Installing Python API ==== | ||
- | 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> | + | > 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 now 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 Python API ==== | ==== Using Python API ==== | ||
Line 103: | Line 152: | ||
| **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) | ||
Line 122: | Line 171: | ||
| **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 | ||
Line 143: | Line 192: | ||
| **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 | ||
Line 164: | Line 213: | ||
| <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 | ||
Line 187: | Line 236: | ||
| **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) | ||
Line 217: | Line 266: | ||
| **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) | ||
Line 242: | Line 291: | ||
| 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) | | ||
Line 256: | Line 305: | ||
| 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) | | ||
| ^^ | | ^^ | ||
Line 267: | Line 316: | ||
| 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) | | ||
| ^^ | | ^^ | ||
Line 277: | Line 326: | ||
| **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 336: | ||
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> ^^ | ||
Line 291: | Line 379: | ||
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> | ||