Make event driven Arduino applications with the MicroQt library
MicroQt is an Arduino library that enables event driven applications on the Arduino platform. This is realized by load monitoring event loops, timers and signals similar to those in the Qt framework.
Features
Signals
Signals make it easy to implement the observer pattern while avoiding the boilerplate code. You can send signals with type-correct event information to connected callback functions and object member functions. This may be used for timeouts, user interfaces like buttons and asynchronous I/O.
EventLoop
MicroQt has an event loop that must be executed in the loop() function. Tasks registered in that event loop are called periodically. The built-in timers register themselves, but you can also register your own tasks, such as polling for button state changes. In addition, you can enqueue events whose execution is delayed until the control returns to the event loop. Since they block the event loop, it is important that tasks and events can be processed quickly.
Load Monitoring
The current utilization of CPU and RAM can be displayed at regular user-defined intervals.
The interval can be set by eventLoop.setLogIntervalMs(…) and disabled by setting it to 0.
The current load is printed on the serial port as follows: CPU Load: 11% | RAM Load: 22% (467 of 2048 bytes)
Timers
Timers are used to call functions periodically or once after a specified interval. Since they run in the event loop and a task or event can block it, the correct timing cannot be guaranteed, but it is appropriate in most cases.
Synchronizers
Synchronizers can be used to wait for a specific event, like a WiFi connection at startup. They appear to block, but in fact they transfer control to the event loop, so that it can continue to process timers and events.
Examples
There are several examples implemented in the library.
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