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Hey thank you. Arduino is great for interacting with electronics of all sorts so if you learn to code Arduino, it will help you a lot on your journey. I learned it in School, in the University and tinkering around at home :)

True 😅

It wouldn’t hurt for sure but will it help? When using mosfets you will need this resistor to keep the gate from floating when Arduino is in a high impedance state. The NPN needs a base current to become conducting, so the additional resistor should not be required.

@@playduino Even a BJT is a voltage controlled device. If you don't believe me, just read The Art of Electronics and/or the Ebers-Moll equations. It's much easier to use the calculation approximations for current with BJTs, which is why almost everyone thinks BJTs are current controlled. Also, why didn't you choose to go with an emitter follower circuit? I think the calculations could have been much easier, and I believe you would not have to use specific items from a BJT data sheet. Anyway, that's just my two cents 😉

thank you for sharing your thoughts but I am not convinced, yet 😅 I looked into Art of Electronics Third Edition. On page 76 you find the circuit that I used to drive an LED.

@@playduino Please take a look at the video titled "BJTs are VOLTAGE-Controlled Current Sources!" on the channel "Lantertronics - Aaron Lanterman" I think that may help convince you 😉

Thank you for sharing the video 🙂 It's an interesting approach to think about the BJT as a voltage controlled device. And it seems accurate. However even if there was a high source impedance voltage on the base that is high enough, it would immediately break down due to the "leakage" current of the transistor into the base. So I still do not see why this resistor should be required. 😅

hi, make sure to download the Apple Silicon Version

Thank you for sharing

thanks for your thoughts! mmWave are very interresting, however I have to admit I would not feel comfortable knowing that these sensors constantly radiate 80GHz in every room 24/7. ESPHome looks like it would fit this project perfectly. With as many sensors as I would like to integrate, ESP32 might be a good choice (instead of using ATmegas). If I decide to pick ESP32, I might use POE to power everything and use ethernet for communication. I could still use Arduino IDE instead of ESPHome for teaching 🤔

Thank you for the feedback :) I think I forgot to mention that I will mount this sensor to the ceiling in every room :) but simple switches are a very good idea. I think I will add one multi-purpose button and one reset button, just in case

thank you for the feedback. I agree, it is a little bit much for one video. I'm afraid I was too enthusiastic :D if you have not already, please check out my second video about this project, I go through the code again and refactor it so that it looks nice, I also fixed some bugs: th-cam.com/video/ACn4-3X8LvY/w-d-xo.html I record the angles of the servo every 10ms in both x and y axis, I also record if the light should be on or off at any given moment of the recording. for example the start of xServoValues array could look like this: [90, 90, 90, 91, 91 , 92, 92, 93 ,94 , 95 ,96 ...] when I playback, I loop through this values. I set the servo to xServoValues[0] which is 90, after 10ms I set it to xServoValues[1] and I do this again and again until I reach the end of the array. yes this could also be used with stepper motors. you can increase the time between measurements. in theory you could even interpolate between measurements to make it smooth again but this will only work if up to a certain limit. the best way would be to use external memory or a microcontroller with more memory

@@playduino Thanks for the reply. It helps and I appreciate it very much. So, my request is, please make some videos that address the things we talked about here. 😀 Also, I would like to send you pictures of my project, if you have a "junk" email address that you don't mind posting here. I'm hoping that you will be able to be successful in your TH-cam endeavors and will be able to post more projects. Thanks again. Regards

feel free to send me some infos / pictures: youtube@playduino.com

@@playduino Thanks. I sent an email last week. Did you receive it okay?

@@KW-ei3pi Hi, yes I just answered.

On Arduino Uno R3 there are only Pull-Up resistors which means they pull the signal HIGH (1) so the switch has to be connected to GND and will result in 0 when pressed

Thank you 😊

thank you very much for the detailed suggestions. I will use them in the next video :)

thank you! yes this is true, digitalWrite is slow, if you need fast IO, you better directly work with the registers - however in this case the problem was delayMicroseconds(): the largest value supported is 16383 🥲

😂 you are correct, sorry for the confusion . The thing is, 1.5ms should be 90 degrees, but in my case it was more like 110. so the maximum input in my case would be maybe maybe 145 degrees which then results in 180 real degrees

Ok, now you lost me. I’ll have to let that sink in.

Wow, so you can‘t even drive a standard LED 😳

wow thank you for pointing this out. I was not aware of this delayMicroseconds() limitation! I agree that using types like uint32_t is safer, however with beginners in mind I will keep using the simple data types. I try to avoid everything that would have scared me away as a beginner back in the days 😅

Thank you! Interesting topic indeed, I will look into it.

well done =D

if (true) is always to, so whatever is written inside the {} is always executed. You will not find this in a normal program because it makes no sense, I just used it to create a different scope :)

Hi, instead of delay(15) you could use the code shown in this video and then handle the servos instead of blinking the led (what I did)

@@playduino would you still have the code ?

Hi the thing is, I do not know exactly what you are trying to do. However I think in your case the simplest solution is actually to use a library called TimerOne. You can keep your working blocking DF-Mini code in the loop. And then have a timer isr function called every 15ms. Inside you change the angle of the servo. You will need two static volatile global variables, one for current angle (int) and one for the direction(bool). Inside or the isr you increment the angle if direction true and decrement the angle is the direction is false. If you hit the maximum angle you need to change direction to false. If you hit the minimum angle you need to change direction to true. Put all this logic into ISR, but don’t put a delay into the ISR. You do not need it, because the ISR is called every 15ms. I’ll upload a video about TimerOne soon. But if you look at example code I’m sure you can do it

@playduino HI well what I am trying to put together is a sketch for a wig-wag (sweep servo) using a IR sensor and a DF-Mini player.

I agree, thank you for sharing :)

Thank you for the feedback! I think the compiler optimizes both versions to the same result all the time.

thank you for the nice feedback and sharing your project. I already covered potentiometers in this video: th-cam.com/video/t7TW546GS3E/w-d-xo.html I also used a button + debouncing in the dice project th-cam.com/video/rmQqDoofxSI/w-d-xo.html my videos are intended for beginners. So in order to cover stepper motors + drivers I will have to cover a lot of other topics first. I might eventually get there but I cannot tell you how long it will take

@@playduinoThanks for the reply. I'm going back to watch your previous. I look forward to all of you future videos. I'll share a programing problem that I'm trying to solve, as it might give you ideas for a future video. I'm using a Potentiometer to set the speed of my Stepper motors. Using the map function to convert the Pot reading to a number that is passed to delayMicroseconds, between HIGH and LOW sent to the Driver. Stepper motors don't like to start at a high speed, but rather need to "ramp up" to higher speeds. So I'm trying to take the mapped number and if it is a number below 300 (a short delay) use a "for" loop to pass a higher number (500) and then a progressively lower number to the delay till it reaches the mapped number from the Pot. I've had some success, but am not there yet. I'm using one variable to contain the number from the "for" loop, but I may have to use more than one. I think I will get there, but my code will likely be long and inefficient. If you enjoy coding, you like solving problems. This one is quite challenging. Regards.

this would make a great video! let's see who is faster :D please let me know when you found a solution that works for you

@@playduino This simple code seems to work and demonstrates the concept without all the hardware: int pd; //Pulse Delay int myDelay; //Ramp up Delay void setup() { Serial.begin(9600); pd=300; myDelay = 500; } void loop() { if (pd < myDelay){ for(myDelay = 500; myDelay > pd; myDelay = myDelay -1){ Serial.println(myDelay); delayMicroseconds(12000); } } else myDelay = pd; Serial.println(myDelay); delayMicroseconds(myDelay); }

@@playduino Hey. How are you doing? I thought that you were going to come up with some code to accelerate a stepper motor. ??? I have been working on it for a month and still haven't come up with working code. I've eliminated the potentiometer and just have a button to start the motor, accelerate from a set low speed to a set top speed, then stop when I release the button. Achieving acceleration is not to difficult, but achieving linear acceleration is difficult. Thanks. Regards.

Thank you, good idea

Thank you very much for sharing!

I had a very bad feeling about the break inside the function 😂 thank you for the clarification

you are absolutely correct, after rewatching my video, I have to admit that my words are very misleading.

Thank you for the feedback! Can you tell us more about when you would use const and when you would use #define? I‘m always thankful to learn more.

@@playduino Well, I am not an Arduino coder. I am c++ coder. Maybe it is different here. I always use define only, if i can't code it different (for example if i want to code different lines for different CPUs or operating systems). It helps reading the source if you have a lot of defines that are used for other stuff than just doing a const. Not sure if there are also other advantages, I must rethink about it. In the arduino reference about "const" they also wrote in the notes/warnings section: "In general const is preferred over #define for defining constants." So if you don't know why you are using #define instead of const, then const if the better variant.

fair point, thank you very much for sharing@@Volker-Dirr

#define should be used only when necessary, e. g. if you plan to later use #if or #ifdef with that definition.

@@playduino define just copies whatever you have defined to the areas where you used it, a variable will actually be stored in memory and then be passed to the function or whatever you are doing with it. So if you define a pin for example and then use that lets say 3 times, the pin number will actually be copied 3 times in you code. If it's a variable it will only be there once. #define is mostly used for example for debugging where if you use #if or #ifdef that code will not be compiled and will free up memory on the arduino if the condition doesn't meet up.