WEBVTT 00:00.240 --> 00:06.930 So great, you have learned how to use interrupts and as a small parenthesis, how to use the Internet, 00:07.230 --> 00:07.680 don't know. 00:07.680 --> 00:12.480 Let's forget about these debates and let's fully focus on the interrupts themselves. 00:12.930 --> 00:14.760 So to correctly use interrupts. 00:14.940 --> 00:21.900 You have to be careful and aware about what you can and can't do and what you should and shouldn't do. 00:22.500 --> 00:27.850 Here is a quick list of the best practices and warnings that will help you when working with interests. 00:28.440 --> 00:35.130 So first, an interim function does not return any result and does not receive any parameter. 00:35.580 --> 00:41.190 So if you want to get on, modify some variables in your program, you will have to modify global variables 00:41.460 --> 00:43.290 inside the internal function. 00:43.710 --> 00:47.880 And note that for any viable you modify inside and interrupt, you should. 00:47.880 --> 00:56.010 But the volatile key word in front of the data type, when you declare the variable now inside to enter 00:56.010 --> 01:03.880 a function, you only want to write code that goes very fast to execute, for example, toggle available. 01:04.350 --> 01:06.510 Basically, that's all you should aim to do. 01:06.510 --> 01:10.550 In the interim, you should avoid doing any action in any threat. 01:11.030 --> 01:17.550 Just use the Interop to toggle available and then in your void loop function, check for that variable 01:17.550 --> 01:19.940 and execute annexion accordingly. 01:20.430 --> 01:27.300 If you stay too long inside an interrupt, you might miss important data you receive in your voice function. 01:27.540 --> 01:33.240 Or you could miss another interrupt that is deactivated while you are in the current one. 01:33.600 --> 01:39.120 Now, if you want to use time functionality inside and interrupt, be extra careful. 01:39.630 --> 01:44.160 First, the delay function won't work and delay microsurgeons. 01:44.160 --> 01:51.000 Wolk's but as you want to optimize the speed, you definitely don't want to intentionally wait in the 01:51.000 --> 01:53.750 interrupt, so don't use any of them. 01:54.180 --> 02:01.110 Something very useful can be to get the time at the beginning of you in 30 minutes and micros will give 02:01.110 --> 02:07.460 you the current time just before the entire function starts, but then inside it to interrupt function 02:07.770 --> 02:16.270 minutes will not increase and micros will work accurately about one or two milliseconds and that's it. 02:16.440 --> 02:20.460 The thing is, you don't want to spend even one millisecond on the interrupt. 02:20.850 --> 02:24.070 You just want to toggle some level and then exit. 02:24.690 --> 02:30.880 So just use Milice on micros to get the time at the beginning if you need it, but no more. 02:31.470 --> 02:34.440 And finally, simple doesn't work in the Interent. 02:34.950 --> 02:40.020 If you want to bring something when an interrupt was triggered, you will have to do it in the void 02:40.020 --> 02:46.710 loop function and find a way to notify the loop when to interrupt was triggered to conclude. 02:46.710 --> 02:53.190 You can see that there are many drawbacks and limitations about interrupt interrupt a powerful Ardino 02:53.310 --> 02:53.880 function. 02:54.090 --> 02:58.950 But to use with care, with the information you have here, you should be fine. 02:59.280 --> 03:05.550 And because all those limitations and things to care about, it's best to use interrupt only when you 03:05.550 --> 03:09.220 really need them when designing a new project. 03:09.360 --> 03:14.130 Always ask yourself if what you want to achieve can just be done with pulling. 03:14.620 --> 03:16.760 If yes, then use pulling. 03:16.950 --> 03:23.220 If, however, you might miss some data using, pulling or get information a little bit too late, then 03:23.370 --> 03:24.600 go with interrupts.