WEBVTT 00:00.150 --> 00:07.230 And now here is the solution to avoid using delays, so you have seen how to use the minis and macros 00:07.230 --> 00:13.200 function to get the time, you have also discovered how to compute the duration of connection with those 00:13.200 --> 00:13.680 functions. 00:14.040 --> 00:19.620 And now we are going to use all of this knowledge in order to reproduce the behavior we had with delay, 00:19.630 --> 00:21.180 but without using delay. 00:21.450 --> 00:24.260 So for this, I'm going to make a simple test. 00:25.050 --> 00:31.290 I want to print something every 500 musician in the loop function so they'll begin. 00:34.590 --> 00:35.050 OK. 00:35.070 --> 00:45.240 And in the function, I'm going to do that to bring in a load, and so we have to delay 500, that would 00:45.240 --> 00:47.210 be with the delay function. 00:47.230 --> 00:53.520 OK, so gate to basic program, we bring Telo every five hundred milliseconds and now let's remove the 00:53.520 --> 00:56.740 delay and let's see how we can do without it. 00:57.060 --> 01:02.370 So of course if we just applaud the program like this, we don't print hello every 500 milliseconds. 01:02.370 --> 01:04.770 We print at full speed. 01:05.040 --> 01:07.830 So the full speed of the original execution. 01:08.370 --> 01:15.090 OK, so to be able to print hello every five hundred milliseconds, we're going to need to check the 01:15.090 --> 01:20.720 duration between the current time here in the Loop and the last time. 01:20.730 --> 01:24.990 So the previous time we have printed on the same monitor. 01:26.040 --> 01:32.460 And if the duration so the difference between the current time and the last time we have done the action 01:32.760 --> 01:37.560 is greater than 500 milliseconds, then we can execute the action. 01:37.920 --> 01:39.960 So we would need to store the previous time. 01:40.590 --> 01:43.170 I'm going to create a global viable here. 01:44.810 --> 01:54.440 And signed long and name its previous time, not just previous time, OK, but previous time still rates. 01:54.470 --> 02:00.220 So we know it's the previous time we have used the sale print function that we are going to use here 02:00.710 --> 02:01.180 and this. 02:01.190 --> 02:05.060 So I could just initialize it to zero to merely. 02:05.060 --> 02:10.410 So I'm just going to use Milli's because when the program starts, this would be zero. 02:10.430 --> 02:12.800 So this would just be executed. 02:12.830 --> 02:18.050 So this value is declared and defined with this value. 02:18.400 --> 02:23.930 So now in the loop function, what I'm going to do is I'm going to unsigned long. 02:25.340 --> 02:26.070 Crunch time. 02:26.380 --> 02:29.090 All I can right now. 02:30.180 --> 02:31.700 Equal to miss. 02:33.340 --> 02:37.440 So every time we enter the loop, we check what is the current time? 02:38.860 --> 02:44.190 And then I'm going to do if the condition, if the time No. 02:45.390 --> 02:55.320 Minus the previous time the sale printed, something here is greater than we want five hundred, I'm 02:55.320 --> 03:03.630 writing 500, then I execute this book of code and I put the sale inside the block of code. 03:05.680 --> 03:11.950 OK, so quick recap of what happened here, we create a viable to stop the previous time we have printed 03:11.950 --> 03:12.570 on the sale. 03:12.700 --> 03:19.390 OK, we initiate easy to zero at the beginning, of course, and then you loop it going in a loop. 03:19.900 --> 03:23.770 We take the time now, which is the time we meet. 03:24.040 --> 03:30.100 OK, so every time we go in the loop, we check what is occurring and then we make the difference between 03:30.100 --> 03:35.360 the current time, time now and the previous time we have printed on the same. 03:35.560 --> 03:42.290 OK, so if you're running from the last lesson we do this, you are just creating a duration. 03:42.310 --> 03:43.930 OK, time now. 03:43.930 --> 03:46.750 Minus time in the past is the duration. 03:47.230 --> 03:50.380 This duration must be greater than five hundred. 03:50.410 --> 03:51.970 So we execute the action. 03:52.420 --> 03:57.880 OK, so every time we're going to look at said the beginning this would be one and then two, three, 03:57.880 --> 04:03.430 four, five, etc. So this will not be greater than five hundred. 04:03.430 --> 04:05.730 And then we don't execute this action. 04:06.370 --> 04:13.720 So not when the minutes reaches five hundred for the first time, this would be greater than 500. 04:13.730 --> 04:14.980 So maybe more. 04:14.980 --> 04:18.620 Five hundred and one, because it's really greater than that. 04:18.700 --> 04:23.830 When this is equal to five hundred and one or more, we enter the. 04:25.080 --> 04:32.360 But then we need to do something because the previous time, so you'll print will always be zero here 04:32.460 --> 04:34.220 because we have initialize it to zero. 04:34.230 --> 04:40.340 So this condition after the minutes here reaches five hundred and one will always be true. 04:40.530 --> 04:44.500 And so we will keep printing this very, very fast. 04:44.520 --> 04:49.020 So what we need to do is that whenever we enter this block of code so we can do an action. 04:49.020 --> 04:51.660 And we said the previous time. 04:54.720 --> 04:55.920 The current. 04:59.760 --> 05:07.070 So if the current time is five hundred, about 500, then we are going to enter this and then the previous 05:07.070 --> 05:14.780 time will become five hundred, which means that not when we go in the loop again, but let's say now 05:14.780 --> 05:16.550 the time is five hundred and ten. 05:17.660 --> 05:23.400 The previous time would be five hundred, which means that this is not greater than five hundred. 05:23.480 --> 05:31.640 OK, but we are only going to go back to the if when the time now is equal to 1000 or more. 05:32.390 --> 05:33.670 But let's actually try this. 05:34.550 --> 05:39.530 I'm going to upload old, let's say, without delay. 05:41.840 --> 05:50.150 And let's use the same lingo here, and you would see hello, hello, printed every five hundred milliseconds. 05:50.390 --> 05:50.920 Great. 05:51.470 --> 05:55.480 So it works and we haven't used any day here, as you can see. 05:56.240 --> 06:00.540 So now, of course, this is a little bit more code, but what is the advantage here? 06:01.010 --> 06:04.050 The advantage is that you never block the instructions. 06:04.070 --> 06:06.350 OK, this will run at full speed. 06:06.740 --> 06:09.650 OK, this takes very little time to do. 06:09.670 --> 06:10.970 This is just a condition. 06:11.300 --> 06:14.440 And this is just you set value inside of value. 06:14.460 --> 06:20.570 So this will take almost no time, which means that if you have a second action, you can do this. 06:20.840 --> 06:26.750 The second action in the loop function here using a similar structure and thus you can do many things 06:26.750 --> 06:27.570 at the same time. 06:27.590 --> 06:31.520 OK, you don't block the program anymore with the delay function. 06:32.000 --> 06:32.380 All right. 06:32.390 --> 06:33.460 And let's come back to this. 06:33.470 --> 06:35.020 I'm going just to improve a little bit. 06:35.510 --> 06:36.620 So here I have you. 06:36.710 --> 06:38.470 Five hundred, which is upgraded. 06:38.960 --> 06:40.420 We can do better than this. 06:40.430 --> 06:41.150 We can do. 06:41.640 --> 06:42.220 Let's see. 06:42.230 --> 06:45.740 Unsign long time interval. 06:47.750 --> 06:51.720 So rate right, which is five hundred. 06:52.990 --> 06:59.350 The we use an inside long as well, OK, because everything we compare here, unsane longsword, just 06:59.350 --> 07:05.290 give the same data type and then we are just defining a time interval viable here. 07:05.300 --> 07:07.810 We say Alperin so we know it's for this action. 07:08.440 --> 07:09.550 And so I can just. 07:10.680 --> 07:11.430 Do this here. 07:12.330 --> 07:18.210 OK, this is better if you can avoid hard cutting values inside the education of your code and create 07:18.210 --> 07:26.240 variables instead of constant and know to improve this, I'm going to also just show you something else. 07:28.680 --> 07:30.000 And then let's bring. 07:31.100 --> 07:32.090 Milice here. 07:33.360 --> 07:35.190 So let's see let's see what happens. 07:37.560 --> 07:43.260 So we bring hello, we also the time, so you see five hundred and one, one thousand and two, etc., 07:43.470 --> 07:46.510 and you can see we are shifting a little bit. 07:46.580 --> 07:50.570 OK, the eight, 10, 11 Segan. 07:50.940 --> 07:51.980 But you can see it. 07:52.020 --> 07:53.500 I'm going to remove the scroll. 07:54.090 --> 07:59.460 You can see here, this is not exactly 14 Siggins, OK? 07:59.470 --> 08:05.190 We have twenty eight additional milliseconds and this is a shift that is going to increase every time. 08:05.250 --> 08:05.940 Why is that? 08:06.570 --> 08:09.750 And this is simply because, well, we executed some action. 08:10.110 --> 08:13.400 The action takes some time to execute, basically. 08:13.650 --> 08:19.530 And when you record time now, of course, there is always a little delay that will happen because you 08:19.530 --> 08:20.850 execute the actions. 08:21.270 --> 08:24.630 So what are we going to do instead of sitting the previous time? 08:24.630 --> 08:33.750 So point to time, know what we can do is simply add the time interval I'm going to do plus equal. 08:35.500 --> 08:41.860 OK, so plus equals simply means that you are going to add this to the variable on the left. 08:42.700 --> 08:46.790 So I simply add the time interval to the previous time. 08:46.870 --> 08:53.470 OK, so whenever we execute the action, I'm going to add plus five hundred, which means that all the 08:53.470 --> 08:59.800 small delays that we have added when actually executed some code will not be taken into account. 08:59.950 --> 09:05.120 But if you don't understand exactly that, let's just see the result and you would see that is better. 09:05.650 --> 09:09.730 Now you can see we have 500, so we still have a small delay for the first one. 09:09.970 --> 09:13.330 But then you can see we already have a good volume. 09:13.340 --> 09:16.500 So we don't have a shift here. 09:16.840 --> 09:24.970 You can see after 13 Segan after 14 seconds, OK, we have 14 and then zero zero one. 09:25.630 --> 09:31.960 So you can see there is exactly 500 milliseconds before each instruction. 09:32.950 --> 09:33.280 All right. 09:33.290 --> 09:39.190 So to recap, first, you create an unsigned, long previous time for the action. 09:39.970 --> 09:44.260 You initialize to zero images and you create a time interval. 09:44.380 --> 09:48.960 OK, the timetable will be basically what you want to put in your delay here. 09:49.040 --> 09:53.290 Five hundred milliseconds, then in the loop function, you get the time. 09:53.890 --> 09:55.120 Time now with Milice. 09:55.540 --> 10:02.740 And then for each action you want to do, you check the difference between the time now and the previous 10:02.740 --> 10:03.890 time you did the action. 10:03.940 --> 10:05.470 This gives you a duration. 10:06.500 --> 10:13.880 You check if the direction is greater than the time interval, you have said, if, yes, you do direction 10:14.450 --> 10:20.960 and then you add the time interval to the previous time, which means that you are only going to go 10:20.960 --> 10:26.540 in if again after the time interval has passed another time. 10:27.140 --> 10:27.520 All right. 10:27.530 --> 10:33.770 So this concept is not the easiest concept to understand, but with the following hands on lessons and 10:33.770 --> 10:39.500 with the following practice exercises, you would be able to get a better grasp and then, of course, 10:39.500 --> 10:42.170 come back to this lesson to better understand.