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Buzzer

raspbot.actuators.buzzer.Buzzer

Controls the on-board piezo buzzer via I2C register 0x06.

Access via Robot.buzzer.

The Buzzer is fully non-blocking. Schedule a beep or pattern with beep() / pattern(), then call update(ct) on every main-loop iteration to advance the internal state machine. No time.sleep() is ever called.

Methods

on()

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def on(self) -> None

Turn the buzzer on immediately (raw hardware command).

off()

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def off(self) -> None

Turn the buzzer off immediately (raw hardware command).

beep(duration=0.2)

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def beep(self, duration: float = 0.2) -> None

Schedule a single non-blocking beep of duration seconds.

The buzzer turns on immediately. update() will turn it off after duration seconds. Any previously scheduled sequence is cancelled.

Parameter Type Default Description
duration float 0.2 How long to beep, in seconds

pattern(on_time, off_time, count)

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def pattern(self, on_time: float, off_time: float, count: int) -> None

Schedule a non-blocking repeated beep pattern.

The first beep starts immediately. update() drives all subsequent on/off transitions without blocking.

Parameter Type Description
on_time float Duration of each beep (seconds)
off_time float Silence between beeps (seconds)
count int Number of beeps

update(ct)

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def update(self, ct: float) -> None

Advance the buzzer state machine.

Call this on every main-loop iteration with ct = time.monotonic(). It is cheap (a float comparison) when nothing is scheduled.

Parameter Type Description
ct float Current time in seconds (from time.monotonic())

is_active

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@property
def is_active(self) -> bool

True while a beep or pattern is in progress.

Examples

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import time
from raspbot import Robot

with Robot() as bot:
    # Schedule a 200 ms beep -- returns immediately
    bot.buzzer.beep(0.2)

    while True:
        ct = time.monotonic()
        bot.buzzer.update(ct)   # drives the on/off transition
        time.sleep(0.001)

    # Wait until the beep finishes before doing something else
    while bot.buzzer.is_active:
        ct = time.monotonic()
        bot.buzzer.update(ct)
        time.sleep(0.001)

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import time
from raspbot import Robot

with Robot() as bot:
    # SOS pattern -- all non-blocking
    bot.buzzer.pattern(0.1, 0.1, 3)   # ...

    while bot.buzzer.is_active:
        bot.buzzer.update(time.monotonic())
        time.sleep(0.001)

    bot.buzzer.pattern(0.3, 0.1, 3)   # ---
    # ... and so on

See also