Welcome to pyFirmata’s documentation!¶
Module reference:
Installation¶
The preferred way to install is with pip:
pip install pyfirmata
If you install from source with python setup.py install
, don’t forget to install pyserial
as well.
Usage¶
Basic usage:
>>> from pyfirmata import Arduino, util
>>> board = Arduino('/dev/tty.usbserial-A6008rIF')
>>> board.digital[13].write(1)
To use analog ports, it is probably handy to start an iterator thread. Otherwise the board will keep sending data to your serial, until it overflows:
>>> it = util.Iterator(board)
>>> it.start()
>>> board.analog[0].enable_reporting()
>>> board.analog[0].read()
0.661440304938
If you use a pin more often, it can be worth it to use the get_pin
method of the board. It let’s you specify what pin you need by a string, composed of ‘a’ or ‘d’ (depending on wether you need an analog or digital pin), the pin number, and the mode (‘i’ for input, ‘o’ for output, ‘p’ for pwm). All seperated by :
. Eg. a:0:i
for analog 0 as input, or d:3:p
for digital pin 3 as pwm.:
>>> analog_0 = board.get_pin('a:0:i')
>>> analog_0.read()
0.661440304938
>>> pin3 = board.get_pin('d:3:p')
>>> pin3.write(0.6)
Board layout¶
If you want to use a board with a different layout than the standard Arduino, or the Arduino Mega (for wich there exist the shortcut classes pyfirmata.Arduino
and pyfirmata.ArduinoMega
), instantiate the Board class with a dictionary as the layout
argument. This is the layout dict for the Mega for example:
>>> mega = {
... 'digital' : tuple(x for x in range(54)),
... 'analog' : tuple(x for x in range(16)),
... 'pwm' : tuple(x for x in range(2,14)),
... 'use_ports' : True,
... 'disabled' : (0, 1, 14, 15) # Rx, Tx, Crystal
... }
Ping support (pulseIn)¶
If you want to use ultrasonic range sensors that use a pulse to measure distance (like the very cheap and common HC-SR04
- See datasheet,
you will need to use a pulseIn compatible Firmata on your card.
You can download it from the pulseIn branch of the Firmata repository:
Simply connect the sensor’s Trig
and Echo
pins to a digital pin on your board.
And then use the ping method on the pin:
>>> echo_pin = board.get_pin('d:7:o')
>>> echo_pin.ping()
1204
You can use the ping_time_to_distance
function to convert
the result of the ping (echo time) in distance:
>>> from pyfirmata.util import ping_time_to_distance
>>> echo_pin = board.get_pin('d:7:o')
>>> ping_time_to_distance(echo_pin.ping())
20.4854580555607776
NOTE¶
The codes will only work if you download and load the pulseIn:: code on the Arduino board! It has to be exactly the code quoted!
credits¶
links¶
Official Discord Server_:
My Discord Username: Aril Ogai#5646