![]() ![]() But what if the program has to keep running because other tasks need to be done regularly? And what if processing these tasks takes longer than pressing the button? That’s where the interrupts are helpful.įor an interrupt, you need two things, namely a trigger and an action (Interrupt Service Routine = ISR). If a loop() pass is shorter than a button press takes, then you could insert the digitalRead() query without a blocking element.īoth may be acceptable in some circumstances.So you stop the program at this point until the button is pressed. You permanently query the button state, for example in a while loop.Whether the button was pressed could be queried with digitalRead(). ![]() Now imagine that, for example, an LED is to be switched on or off when a push button is pressed. one instruction (statement) is processed after the other. In programming, we are used to thinking sequentially, i.e. ATmega328P – Programming external interrupts on register level.Controlled suspension of interrupts with noInterrupts().Dealing with large volatile variables in ISRs.However, this has made this post quite lengthy, even in two parts.Īfter a general introduction, the first part deals with external interrupts. Maybe one or the other advanced reader will also find some new details. My motivation for writing my own contribution was to go a little deeper into some aspects. There are actually already more than enough articles about external interrupts on the net, and many of them are excellent. In addition, the programming of interrupts is quite hardware-specific. However, there are a number of stumbling blocks when using them. Interrupts can be used to elegantly overcome many challenges in programming Arduino boards or other microcontrollers. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |