class `PWM`¶

Example

# Import PWM class
from robot_hat import PWM

# Create PWM object with numeric pin numbering and default input pullup enabled
p0 = PWM(0)
# Create PWM object with named pin numbering
p1 = PWM('P1')


# Set frequency will automatically set prescaller and period
# This is easy for device like Buzzer or LED, which you care
# about the frequency and pulse width percentage.
# this usually use with pulse_width_percent function.
# Set frequency to 1000Hz
p0.freq(1000)
print(f"Frequence: {p0.freq()} Hz")
print(f"Prescaler: {p0.prescaler()}")
print(f"Period: {p0.period()}")
# Set pulse width to 50%
p0.pulse_width_percent(50)

# Or set prescaller and period, will get a frequency from:
# frequency = PWM.CLOCK / prescaler / period
# With this setup you can tune the period as you wish.
# set prescaler to 64
p1.prescaler(64)
# set period to 4096 ticks
p1.period(4096)
print(f"Frequence: {p1.freq()} Hz")
print(f"Prescaler: {p1.prescaler()}")
print(f"Period: {p1.period()}")
# Set pulse width to 2048 which is also 50%
p1.pulse_width(2048)

API

class robot_hat.PWM(channel, address=None, *args, **kwargs)¶

Bases: I2C

Pulse width modulation (PWM)

REG_CHN = 32¶: Channel register prefix

REG_PSC = 64¶: Prescaler register prefix

REG_ARR = 68¶: Period registor prefix

CLOCK = 72000000.0¶: Clock frequency

__init__(channel, address=None, *args, **kwargs)¶

Initialize PWM

Parameters: channel (int/str) – PWM channel number(0-13/P0-P13)

freq(freq=None)¶

Set/get frequency, leave blank to get frequency

Parameters: freq (float) – frequency(0-65535)(Hz)
Returns: frequency
Return type: float

prescaler(prescaler=None)¶

Set/get prescaler, leave blank to get prescaler

Parameters: prescaler (int) – prescaler(0-65535)
Returns: prescaler
Return type: int

period(arr=None)¶

Set/get period, leave blank to get period

Parameters: arr (int) – period(0-65535)
Returns: period
Return type: int

pulse_width(pulse_width=None)¶

Set/get pulse width, leave blank to get pulse width

Parameters: pulse_width (float) – pulse width(0-65535)
Returns: pulse width
Return type: float

pulse_width_percent(pulse_width_percent=None)¶

Set/get pulse width percentage, leave blank to get pulse width percentage

Parameters: pulse_width_percent (float) – pulse width percentage(0-100)
Returns: pulse width percentage
Return type: float

class PWM¶

class `PWM`¶