ScaleTriggerBase

class ScaleTriggerBase

Bases: object

Base class for defining custom box scale behavior.

While a task is running, the box scale (SCALE_BOX, only when USE_BOX_BOARD is ON) is read in its own thread every self.period seconds, and on_weight is called with every measurement. Override on_weight to react to it. The reading runs only while a task is active.

on_weight runs in the scale reader thread, not in the task thread: keep it fast, the next reading waits until it returns.

You have access to self.task, so any variable or function of the running task can be used.

__init__() → None

Initializes the ScaleTriggerBase instance.

Methods

on_weight(weight: float, timestamp: float) → None

Called after every reading of the box scale. Override me.

Parameters:

• weight (float) – The weight in grams.

• timestamp (float) – Raspberry timestamp of the reading, the same clock as time_utils.now_timestamp(), so it can be passed to self.task.register_raspberry_event.