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This is a topic among many that I would like to make a video on for my hobbyist electronics business that I am in the process of opening up so I thought I would share my very early stage written up tutorial to the fine people of the LTT Forum. I figured I would go full master exploder with the juicy bits to blow your mind. Later on I will include hardware and software examples and possibly how this correlates to motherboard RGB headers. I will also probably be writing other tutorials as I go along. Probably more basic ones to start with after this for the less initiated lol. Sorry for the terrible quality of the writing as I can read and write better C++ then and I can read and write English (even though its my first language lol.) Probably will turn this into a mega thread with all the tutorials that I write up. Or maybe throw them up as blog posts with links idk. Depends on how receptive the community is. TODO: Remove vulgar language Add figure numbers for each image and subsequent referrals in each applicable paragraph Resize images for better formatting Any images that are not from the datasheets replace with my own Make some images related to data Write Code Create hardware designs Create Github repo Move everything into the github repo Find more issues with this post and subsequently log them here. This article is intended as high level overview on various types of RGB strips, their operation and techniques for successfully utilizing them. The LEDs being discussed are single colour 4 pin RGB strips, 3 pin addressable RGB WS2812B strips and finally 4 pin addressable RGB APA102/SK9822 LED strips. All or most of this information will also apply to bare LEDs of these types and LED matrices of these types as well. If there is any information that you believe to be incorrect please let me know. If there is any spelling mistakes, grammar or formatting issues please let me know as well. I will be more than happy to fix any issues with this article. Any comments or questions please feel free to post! Definitions for the context of this write up: RGB is Red, Green, Blue RGBW is Red, Green, Blue, White (the reason I use white and not amber is that A is typically associated with alpha channel which is what lets you set the opacity of pixels in an image so evidently that's not the right term to be using in our context because LEDs have no opacity value. ) We as humans typically use numbers in the decimal system or base 10. This means we have ten distinct digits per position ranging from 0 to 9. Exceeding 9 would now start counting in the next highest position e.g. 10. Each number position is 10 times the position to the right of it. So to compose a number such as 4682 you would break it down into thousands, hundreds, tens and ones or 4000 + 600 + 80 + 2 However computers work in a completely different numeral system. This system is known as binary meaning there are only two digits per position which are 0 and 1. Except instead of Base 10 we're now Base 2 so each number position is 2 times the value to the right of it. So to count in binary you would go from 0000 which is decimal 0. 0001 which is decimal value 1. 0010 is decimal value two. 0011 is decimal value 3. 0100 is decimal value 4..so on so forth. Individual positions in binary are commonly referred to as bits. So a 16 bit number would have 16 positions like so 0100 0010 0000 0010 0100. A Byte is a collection of 8 bits and it is the smallest unit of data that a microprocessor will use. From now on I will use () to represent individual bytes RGB colour information in computers is a numerical representation of intensities (also known as saturation) of the primary colours or channels in binary. These are typically stored as 24 bits or 3 Bytes of data for a total of 16,581,375 colours. RGBW is 32bits or 4 Bytes of data for a total of 4,228,250,625 colours. You can get more color depth and formats but this beyond the scope of what I want to write as its not applicable to what we want to do. This gives each channel or colour 8 bits of data each for the Intensity of the colour. So in order to get the 16 million colours you would multiply 255 x 255 x 255( x 255 for white). So in order for us to get full solid red colour we would have a value of 255 for the red byte, 0 for the green byte, 0 for the blue byte or in binary (1111 1111)(0000 0000)(0000 0000). . Lets now say we wanted solid purple for a colour. This would be represented by a mixture of the Red and Blue channels. To numerically represent this it would be 255 for our red byte, 0 for our green byte, and 255 for our blue byte. This in binary is (1111 1111)(0000 0000)(1111 1111). Moving onto computer memory we will look at how everything is stored within a computer. You've probably heard the terms 32bit or 64 bit processors before but what does this actually mean. What this comes down to is the number of bits that the processor can naturally process in addition to how much memory it can address. (There's way more to this but this in it self is a cluster fuck of a subject. Also note to self find a nicer way to put this ) Notice the italics on natural because this leads us into the next portion which is data Words. Words are the natural unit of data for a given processor and what this means by natural unit is that it easily matches the number of bits that our processor can work on. So if we have a 64bit processor that means the word size will be 64 bits or 8 bytes. Onto the memory addressing. A memory address is a binary number that has the same number of bits as your processor. This numbered address corresponds to a byte of data stored in memory. So if you have a 32Bit processor you can only address up to 4GB of RAM (232). If you have a 64Bit processor this is over 17 Exabytes of RAM that you can access(264). So how do you order your bytes of data into memory? Well there are 2 ways which is either Big Endian(BE) or Little Endian(LE) also known as Endianness. In a big endian system your most significant byte (the most significant digits) is stored at the smallest memory address. In little endian we have the exact opposite where the least significant bytes are stored at the smallest address. If you need help visualizing this imagine memory address as a latter. The rung at the bottom is the smallest memory address while the top rung is the biggest memory address. You either put the biggest part of the number followed by the smaller digits starting at the bottom and working your way up or you do the exact opposite where the smallest digits at the bottom working your way up to the top with the bigger digits for big endian and little endian respectively. (If you want a brain twister then try to think about doing both of these methods at the same time because they're computers that work with both.) If you're wondering what an x86 / x86_64 (Intel/AMD 32/64bit processors) use its little endian. So I've explained what binary is and how it is used to represent images and colours and now its time to explain the other side of the coin which is Electrical signals. We will start with and explanation of what Voltage is and how we use it. Voltage is known as an Electrical Potential Difference which is represented by the SI unit Volt or V. This is called a Potential Difference because its a difference of charges or energy between 2 points. This is much like gravitational potential energy where the energy lies between 2 different points or heights. Example: If an object is on the ground it has a potential energy of zero because its already at the lowest point it can be. But if an object is raised to say 10 meters it now has a 10 meter difference in potential energy because it can fall 10 meters to the ground. So now that we know what a potential difference is we can now apply it to voltage. So on a circuit you would have power source such as a battery which has a negatively charged terminal and a positively charged terminal. This now our source of potential difference because one terminal is positive and the other is negative. If this was a car battery for example it would be at 12 Volts which means the positive terminal has positive charge that is 12V higher than the negative terminal. (Though in some unique cases you can have -12V which can be really useful but beyond scope.) By default charges want to balance or cancel them selves out so how is this useful to us? Their desire to be balanced creates immense pressure that when harnessed is how you produce work. So now in a circuit if we force them through a certain path they will now do work for us to get to the other positively charged terminal. So this work that is done could be a light bulb turning on, a microprocessor operating, heating element heating up etc. Electrical Signals are the way in which represent or encode data to a voltage value. This all comes back to numerical representations of a given property. So an Analog signal is way of continuously representing electrical signals from infinity to infinity using voltages. Coming back to numerical representations you would assign a range to a dataset and a range of voltages that corresponds to that dataset. If we were to look at a temperature sensor it has (for our context) 2 properties: 1) The temperature range it is capable of measuring. 2) The voltage range it can output. So if our temperature sensor is capable of measuring 0 to 100 C° and it does this over a range of 0V to 5V then by measuring the voltage we can determine the temperature. So if we measure the voltage and its at 2.5V then we know the sensor is measuring 50C°. Pretty easy right? Lets move on. The binary numeral system that I discussed earlier is extremely useful to electrical signals because a lot of the time they're either on or they're off which is 1 and 0 respectively. This is what's known as digital because the voltage is being expressed by a series of digits. This differs from analog because analog is stateless as it maps to a range and not two different distinct states like digital does. These states are high voltage potential and low voltage potential which maps to binary 1 and binary 0. So that leaves us with only 2 possibilities for a signal which really isn't all that useful on its own. But if we add into the mix the possibility that we can change states over time then we can suddenly do a lot more with it such as represent binary numbers. Now that we know what an Analog and Digital Signal to Clock signals and no its not the thing that you stare at all day when you're in class or at work but it is related. I mentioned previously that digital signals on they're own are not all that useful because you can only do two different things with them which is either turn something on or turn something off. But I eluded to the fact that if you do that over time you can now represent data. So if you have a piece of circuitry that constantly turns on and of at a set frequency you have a clock. The time between two of the same states is a known unit of time. So if we had an awfully slow clock of 10Hz (Frequency represented by Hertz Hz is the count of how many times a specific event happens in a one second period. ) it means that the clock changes between states 10 times per second. So if we were to divide one second by the amount of times our clock pulses (10Hz) you would have 100ms (milliseconds or 0.1 seconds) between pulses. So a clock signal does two things for a circuit it keeps track of time and subsequently provides synchronicity. Lets keep the head hurting train moving and go onto PWM or Pulse Width Modulation. Simply put PWM is a way of representing or translating a digital signal to an analog one using a square wave that vary the width of. PWM has 3 components to it which are duty cycle, frequency and range. We already know what frequency is so we will skip straight to duty cycle which is a portion of time that a digital signal stays in a specific state vs an opposite state represented by a percentage. So if we had a frequency of 100Hz and we held a high signal for half of a clock pulse (or half the duration) we would have a duty cycle of 50%. If we had 5V as our source voltage and we used a PWM with a 50% duty cycle we would be left with a voltage of half of our source voltage so in this case that would be 2.5V. So by varying the duty cycle you now can see how we can represent analog signals digitally. Another thing we have to talk about regarding digital data is data transmission. There's two approaches that exist when transmitting bits one is called Serial and the other is Parallel. Parallel for the most part has been phased out but it still does exist in limited fashions and devices. Parallel data transmission works by sending multiple bits simultaneously to the target device. This can be any number of bits (There's issues with the more lines you add...but out of scope) for example you may have a parallel data connection that uses 8 data lines so that it is capable of transferring 8 bits of data or a byte at a time. This is contrasted by serial data transmission in which a single bit is transferred one by one by a single data line(There are serial protocols that utilize more than one data line). This typically includes a clock signal to synchronize the transmission of the data bit between devices. Depending on the protocol variation (or the device implementation) data may be sent or received on a rising edge or the falling edge of a clock cycle. There's also three primary categories of communication between devices. The most basic is call simplex (go figure) in which data only travels one way at all times. It works by one device sends data to another but the other device doesn't talk back. The other 2 categories allow for data communication both ways. These are called full duplex and half duplex. In half duplex the data line is shared by both devices. This much like walkie talkies where only one person can talk at a time. On the other hand full duplex has at least 2 data lines allowing for both devices to communicate at the same time. This works by one device using one data line while the other is used by the 2nd device to send data back to the first device. At their core an LED you may know as basically a high tech single colour lightbulb. (There's a few exceptions to this but they're beyond scope.) If you give it a voltage and it turns on and if you vary that voltage you change the brightness also known as the intensity. LEDs are type of diode so they typically operate on the 2V to 5V range. If one were to apply 5V to the LED it will be very bright and if we just give it 2V it will barely be on. Knowing that we can map an analog range to this. Now the gears might be turning in your head on how to do so but we just discussed it earlier. The solution is simply PWM this means we can take our 24bit data and translate it into an analog signal. But wait we have a problem LEDs are only one colour so the solution is take 1 LED from each colour that we need and feed it a PWM signal. This is where our RGB data comes in which we will feed each PWM signal (frequency would also be selected but not needed for our example.) the byte that corresponds to the LEDs color. So now if we had the colour Purple we would have the Red and the Blue LED on but not the green. If we wanted white we would turn on each LED to the same intensity (assuming we don't have a white LED channel.). So that's the most basic primitive type of RGB LED strip is where you have 4 wires that are Red channel, Blue channel, Green channel and ground. You might find your self asking why I said you need an LED for each separate channel when there is only one LED for all the colours. This is because they will combine multiple different colored LEDs onto a single package. Lets combine everything discussed and talk about how addressable LEDs work. The working principle of addressable LED's is that instead of applying a PWM signal across the entire strip we will apply it to each individual LED. The way this works is instead of our microprocessor encoding our digital signal to an analog one through PWM we will leave it up to another piece of circuitry that is an Integrated Circuit. This integrated circuit can either be integrated directly into the LED module it self or it can be a stand alone chip on a circuit board with stand alone LED's. These integrated circuits LED modules come in two flavors WS2812B and APA102. The first one we will talk about is the WS2812B as this is the most commonly available. There is a grand total of 4 pins for each module. These are as follows: Vdd (Source Voltage), Di (Data In), Do (Data Out), and Vss (Ground). These modules are at their core are a PWM Shift Register which is an electrical circuit that consists of numerous (24 on this module) storage cells. These shift registers have 2 data pins on them one is for data in and the other is for data out. When you send a data bit to the data in pin you push that data into the first cell. When you send the second data bit it pushes the first bit into the 2nd cell and the 2nd bit occupys the first cell. You do this until you have filled register. It looks a little like this: colour byte >> Shift Register (0010 0101) >> (), (0001 0010) >> (1), (0000 1001) >> (01), .....(0000 0000) >> (0010 0101) Now that you have filled your register you're probably thinking your done but how do you get data to the other LEDs? Well you keep pushing bits down the line because remember there is a Do or Data Out pin. So your register keeps pushing bits out as you push bits in allowing to move data into next led. This whole process is essentially one big pipe where you push bits in on side and they come out the other. The proper term for this is called Cascading. Do you remember endianness well... it also applies the transfer of bits from once device to another but this time there's no memory addresses to deal with but simply is it the most significant bit (MSBit) first out or is it the least significant (LSBit)? In our case with WS2812B LEDs the most significant bit is sent out first. If you look at the diagram you may also notice that the order of the colour bytes is not RGB but rather GRB. We know that Blue is the first byte to be sent. So the order of transmission is Blue LSBit -> Red LSBit -> Green LSBit -> Green MSBit. We also have to take into account that the LEDs at the end of the strip will be first bytes of data that we will send. We have now established how to send data to our LEDs and in what order but there's more to it than that with these LEDs. The reason there is more to it is because these LEDs don't take a simple High signal or low Signal from your microprocessor. If we look at the supplied timing diagram it shows both a high period and a low period for which to encode a binary 1 or a binary 0. This is because these LED's don't have a clock signal into them that allows you to synchronize the data transmission. Instead if you hold your data pin high for x amount of time and then hold the pin low for x amount of time you encode a bit. These timings can be found in the table below. So in order for us to encode a binary 0 we would have to look at T0H and T0L these correspond to high voltage time and low voltage time. So to have a binary 0 you would need to hold the data pin high for 0.4us and then hold it low for 0.85us. To encode a Binary 1 we need to look at the two remaining rows which is T1H and T1L. Which corresponds to 0.8us and 0.45us respectively. So for every bit we need to output we have to see what its binary value is so that we can hold the data pin at the voltage levels for the time needed and then move onto the next bit after that. After we have shifted all the data to the LEDs we then need to use the Reset command to lock the data in after which the LEDs will lock into the colour that we sent. To send the reset signal its as simple as holding the data pin low for 50us after we sent our last bit. One easy way we can achieve sending this data is through PWM because if you look back at the timing diagram it looks awfully like a PWM diagram. You can set your PWM frequency to that of the total bit encode time (assuming nominal) which is 1MHz ( Some microprocessors may be incapable of this.) Now if you set your PWM duty cycle to 64% you will encode a binary 1 ever cycle and if you set it to 32% you will encode binary 0. So now you just have to set duty cycle for every cycle of the PWM to encode your data. Easy Peasy. If your microprocessor is incapable of this you would need to structure your program to account for time that the bit is held high and for the time that the bit is held low and modulate the voltage level that way. Because the WS2812B's are timing based Bit Banging it leaves something to be desired for refresh rates and for the total number of LED's that you can run in total (assuming you have the RAM on the controller to hold as many LED's as you need.) If you say wanted to run these LEDs at 30Hz (30 FPS) you would only have 33ms to update your LEDs and lock them in. So the fastest (According to the data sheet) that we can encode a bit on these LEDs is 0.65us. So lets convert 33ms to microseconds. Shift the decimal place over 3 positions and we have 33000ms per frame to update LED's. We need 50us to send the reset signal so we can take that right of the top so that we have 29950us to work with. So 29950 divide by (0.65us x 24 bits) is 1919 LEDs. You want to run those LEDs at 60FPS well your left with less than half after that. Moving onto the other type of LEDs which are the APA102 LEDs. These guys are very similar to the WS2812B but they have 2 extra pins Ci and Co which are clock in and clock out. Since these have clock pins they use the pulse of the clock and the current state of the Data in pin to encode a binary 1 or binary 0. In addition our data format changes from GRB to BGR. There is also a little bit more information that we have to send at the beginning and end of each frame and with every colour value. At the start of every frame we will have to send a start frame which is 32bits of binary 0's. After this for each LED we will send 3 binary 1 bits followed by a 5 bit (32 level) global saturation modifier. This global modifier will scale the brightness of the LED while preserving the exact colour. After that you will send your data in BGR format starting with the MSbit. Once you're done sending your colour you will end the entire operation with an end frame which is simply another single 32bit group of zero's that are pushed down the line. To recap the APA102's you send a start frame at the beginning of every update to signal that you intend to write new data followed by packets consisting of 3 high bits followed by 5bit global brightness number followed by 24bits of BGR colour data. You repeat this packet for every LED in the string and then finish it off with an end frame consisting of 32bits of zeros to each LED to lock in the colour. This entire process is very similar to a serial data protocol called SPI or Serial Peripheral Interface. Its a 3 wire full duplex synchronous data transmission protocol that has 2 data lines and 1 Clock signal. The Data lines are MOSI or Master Out Slave In and MISO or Master In Slave Out while the clock signal is called SCK. Since the LED's don't communicate back to us we really only need the MOSI line and the SCK line. Many boards allow us to configure how fast we want to send data, whether that data is sent on a rising or falling clock edge and if we want LSBit or MSBit first. So already we can get off very easy by using the hardware features of many microcontrollers and processors. For the APA102 we can send data at very fast rates (10MHz+) and we need to send them on a rising clock edge. That's all you really need for basic APA102 operation. However with the APA102's the data needed in total is a little misleading because you most likely will require more data sent. This more specifically has to do with the end frame. Since these LED's require a rising clock edge to validate data the other LEDs in the line wouldn't have enough time to validate incoming data because the rising edge window is too short. So the way the APA102 designers fixed this is by delaying the data output by about half a clock cycle back so that there's enough time for the next LED to monitor the data line and read the data in. The consequence of this is that for every LED the data gets delayed by an additional half clock. So what the end frame has to do with is that its only purpose is to push the rest of the bits to the last of the LEDs with additional clock pulses. The number of clock pulses needed is half of the LED count because each LED is a half clock more behind the previous LED. So if you only used the datasheets recommend 32bits only 64 LEDs would be locking in the new data. Where as if you send half the number of your LED's as a total bit count each containing 0's you subsequently lock in the data for every LED. The end!!! Now go blow your mind!!!!!

Hi Community, I am new here, I wrote this software for different use's I may have. Any comments about the Cartoon affect on linus? Any comments, opinions, advice, and criticism is greatly appreciated. Cheers, Sean

Hi, so im looking to make a image scroll on hover to show a preview of a webpage. This page is a good example of this https://nycwebdev.io/ . Mine is just a popout image that needs to scroll. I will attach the HTML and CSS to this post. and here is whats currently happening with my code. https://gph.is/g/4L3YoqP I've looked around a lot and cant find a good answer. Thanks in advanced for the help. <div class="col"> <a href="http://www.sekisuiplasticsusa.com"> <div class="card"> <img id="cardimg" src="Manufacturing images\Sekisuibig.PNG" alt="Avatar" style="width:100%;"> <div class="large"> <img src="Manufacturing images\Sekisuibig.PNG" class="large-image" alt="Avatar" style="width:250px; height: 250px;"> </div> <div class="cardtext"> <h6>Sekisui Kasei USA</h6> </div> </div> </a> </div> .large { position: absolute; left: -9999px; z-index: 1000; background-repeat: no-repeat; overflow:hidden; } a:hover .large { left: 20px; top: -150px; border-radius: 4px; box-shadow: 1px 1px 3px 3px rgba(127, 127, 127, 0.15); } a:hover .large-image { transform: translate(0, -25%); } .large-image { transition: all .3s ease-out; margin-left: 0px; object-fit: none; margin-top: 0; object-position: 50% 0%; }

Hello to all developers out here. Can you answer what kind of build are you running,laptop or desktop. In what languge are you primarily coding,and what software´s do you use. I am gonna build pc or buy laptop in next few months,and would like to plan my budget accordingly.

I've been struggling to find a way to do this for a while, i have a laser profiler (scanner) that I have retro fitted to a CNC router to scan surfaces to look at the undulations, I have to export these out of the proprietary software to a .csv file in order to stich multiple together (still working on this but am close) but i have then no way of viewing these images again as the software does not then allow you to import the .csv file back into it and will only open a .lhi file. I don't need it back into that software as i can use fusion 360 to open it, but i need to make it into a file format that will understand. fusion 360 allows a lot of 3d file types, and does have an option to import .csv files but it doesn't seem to work with the way the original software wrights the .csv files I have attched the .csv file for reference any ideas would be greatly appreciated, Thanks csv_file.zip

Everytime I install windows it reboots then goes back to the same install windows screen idk what’s wrong

Hey guys, so I want to get some feedback for this little password generator/manager app I'm currently making for PC (specifically for Windows) as well as getting some advice for the future, so here goes for the advice.. Where can I release the app exclusively for PC (for now) without paying monthly fees? Is it a good idea to make the app open-source? Would this be a good thing to add to a portfolio or should I convert the code to a more well-known language first? (It's all going to be and is coded all in Delphi Pascal, because it's the only language I know at the moment) Any other suggestions and stuff regarding the app's GUI,etc.. I'm still going to tinker and whatnot but I can't do as much as I'd like rn as I'm in my first round of final exams. And this is the pre-pre-pre-alpha version of my final idea for the app, it's only a really basic password generator at the moment. Link to the github of the app : https://github.com/Kiryu02/SimPasGen Thanks in advance for the feedback/advice! Regards Ya Boi Minister

Hi guys just checking if i have this done correctly, or if their is something i need to change before continuing #include <stdio.h> void main(void) { struct examResults { char title[20]; unsigned int score[20]; const int myExam[17]; myExam[0] = 62; myExam[17] = 80; }; }

#include <stdio.h> void main(void) { double y; double x, a, b, c, result; printf("Enter value for y: \n"); scanf_s("%lf", &y); getchar(); { switch (y) { case (y > 0 & y <= 10): printf("y is equal or greater than 0 and smaller than 10"); break; case (y >= 11 & y <=20 ): printf("y is equal or greater than 11 and smaller than 20"); break; case (y >= 21 & y <= 30): printf("y is equal or greater than 21 and smaller than 30"); break; case (y >= 31 & y <= 40): printf("y is equal or greater than 31 and smaller than 40"); break; case (y >= 41 & y <= 50): printf("y is equal or greater than 41 and smaller than 50"); break; case (y >= 51 & y <= 60): printf("y is equal or greater than 51 and smaller than 60"); break; default: printf("Invalid number\n"); } } printf("\n Enter value for X:"); //Gets vlaue for x scanf_s("%lf", &x); //Reads in value for x getchar(); //Waits for input printf("Enter value for A:"); scanf_s("%lf", &a); getchar(); printf("Enter value for B:"); scanf_s("%lf", &b); getchar(); printf("Enter value for C:"); scanf_s("%lf", &c); getchar(); result = (a * pow(x, 2)) + (b * x) + c; } The code keeps throwing an error in visual studio "Expression must have a constant value". Any ideas how to rectify this?

Hi im having trouble getting my case function to work. I enter a number between 0-60 and it is meant to return a @your number is greater than x but less than y. It has to be done with switch statemtents but i dont know how to make this function. I am incrementing my for loop and trying to get it to work that way. Any ideas? #include <stdio.h> void main(void) { int y; double x, a, b, c, result; printf("Enter value for y: \n"); scanf_s("%lf", &y); getchar(); int counter; int min; int max; for (counter = 0; counter < 6; counter++) { // Incraments if statments up to 60 min = counter * 10; // Multiplys counter by 10 max = (counter + 1) * 10; // Allows counter up to 60 if (y >= min && y < max) // If statement for if its between 0<60 { switch (y) { case 'A': printf("y is equal or greater than %d and smaller than %d", min, max); break; case 'B': printf("y is equal or greater than %d and smaller than %d", min, max); break; case 'C': printf("y is equal or greater than %d and smaller than %d", min, max); break; case 'D': printf("y is equal or greater than %d and smaller than %d", min, max); break; case 'F': printf("y is equal or greater than %d and smaller than %d", min, max); break; default: printf("Invalid number\n"); } } } printf("\n Enter value for X:"); //Gets vlaue for x scanf_s("%lf", &x); //Reads in value for x getchar(); //Waits for input printf("Enter value for A:"); scanf_s("%lf", &a); getchar(); printf("Enter value for B:"); scanf_s("%lf", &b); getchar(); printf("Enter value for C:"); scanf_s("%lf", &c); getchar(); result = (a * pow(x, 2)) + (b * x) + c; }

For experienced developers,upcoming one and future ones. What would be your best tips about programming in general. I mean tips like what kind of setup to use,keyboards and languages in general. What would you say is the best branch(i belieave its like this word) would be to go after? What languages should a new coder approach first? How is the lifestyle and routine of a coder? How long till a person is good enough so it cant start working from home or freelance? Anything you think it would be a good tip or reccomendation please post below. If there is topic like this already sorry

x, y = 20, 60 y, x, y = x, y-10, x+10 print(x, y) It returns 50, 30 which means the second line is as good as x, y = y-10, x+10 Why is the first assignment useless? Won't python first assign y = x, then do the operations and then finally gets reassigned?

Hi all,i am in the market for nice keyboard which i will use for typing. I own razer blackwidow atm,and its nice but looking for something more quite. Anyone have used nice mechanical or not keyboard that would fit my need. I would like to keep budget low,i dont need 200 euro keyboard for this

Hey guys, I want some educational advice over whether I should choose Python or MySQL and PHP as my specialization in the course I'm doing next year. The reason why I'm asking is because out of the 2 main tracks that are offered in the course (Web Dev or Software/Mobile Dev), I'm going with Web Dev and I'm unsure as to which specialization would help me more and be more worthwhile for doing web development in future? Thanks in advance for the advice! Regards A confused final year high school student Link for referencing (hope the link works): https://www.aie.ac/tcp-2_30_374-it-systems-developer-nqf5-computer-programmer.html

I bought Laptop 10 days ago.I have option to return it tomorrow and change for something else or get money back. I could trade the laptop hp 15 series(580 euros) for Lenovo ideapad 3(500 euros)with new ryzen 4500u. i would need upgrade any of this laptop since they both come with 8 gb ram(lenovo have 1x4gb soldered) and lenovo is max 12 gb,Hp laptop 16 gb. If i want to build desktop,could i build something better for under 600euros? I dont need gpu,i need 256 or 512 ssd or even better nv.me ssd if its really that much better. 16gb ram minimum. and support for dual monitors i found some companys that sell prebuilt pc with ryzen 3400g,16gb ram 3000mhz,,512nv.me and 450mobo for 530 euros. If anyone have and advice please say what i should do since i need to go first thing in te morning with laptop to return it. I will be coding in Node.js,phyton and java(i just started learning with javascript) Location is Austria.

Just started learning some Java in this online course created by the University of Helsinki. There's a small exercise I'm having trouble with. And here's a link to my code - https://pastebin.com/W0MACx1i Here's a screenshot of the exercise. I'll appreciate any kind of help! The problem: when I enter 2012 for example, it says it isn't a leap year, even though it is!

Hello Friends, So I'm starting my computer science bachelor in September and I have to get a new laptop. I am not gonna play games on the laptop, i own a Desktop already. So the laptop will be used exclusively for University. I really want a 2 in 1 laptop if possible, tho I'm open for other suggestions. I'm currently looking at these two laptops: Yoga C940-14IIL (14", UHD, Intel Core i7-1065G7, 16GB, 1000GB, SSD) HP Envy x360 – 15-ed0902nz (15.60", UHD, Intel Core i7-1065G7, 16GB, 512GB, SSD) I could also get a microsoft surface book 3, altought price inst a problem its +500 bucks at least and I don't see how it would perform better than the other two. Any recommendations are greatly appreciated. Dilgi

Hello! I am currently looking for a new laptop for university, and wondering if I could get some thoughts on whats the best laptop for that environment. Here are some answers to some common questions people may have; What is your budget? $1000-1500 CAD or $750-1120 USD (Though may be willing to increase depending on the laptop) What is the size that you are considering? 14 inch and higher What screen resolution do you want? 1920 x 1080 Do you want to play games with your laptop? No gaming. What other tasks do you want to do with your laptop? Programming and math related stuff. How much storage (Hard Drive capacity) do you need? 500 GB - 1TB What country do you live in? Canada I appreciate any and all thoughts! Thanks!

Is Intel Xeon PHI is out of support from intel now ?, can i get accelereated from Xeon PHI with node.js and php ?, is there any way to tweak node.js nor php internal for that ?

Heyo! I am in the midst of a Simracing wheel-rim DIY, and my Arduino/Coding skills are lackluster. I'm using a ATMEGA32U4 for a Porsche 911 gt3 cup button box + shifters. 10 push buttons, 2 paddle shifters and 2 encoders. = 16 outputs total as the encoders have 2 each. also want to solder a DIN connection to the board, and havent looked up how to do that yet eather. where i am stuck at is that i found a sketch that works from pin 2-10, 14-16. so im missing 1,11,12,13. the visible buttons on the board are 2-10,14-16, A0-A3. so im guessing i need some code to set up A0-A3 as normal pins. also i need code for the Encoders to be correctly red. atm they dont work propperly, (dont work as an individual puls every time i switch position). here are some pictures to feast your eyes on. Any help would be much apprichated! Brg Roth

Budget (including currency): Country: India Games, programs or workloads that it will be used for: Python, Java Other details : I have been interested in low power computing for some time now. Got myself a Raspberry Pi 4, which is great for most of my uses. I have a desktop built around Ryzen 3950X. Now, the desktop consumes 300-350W under slight load, idles at around 200W, while the Raspberry Pi consumes 6W. I can still write my python scripts using the Pi. So I use the desktop only when it comes to the final execution. I was hoping to get a similar low power consuming SBC which is x86 based and has a little bit of more power, memory, threads than the pi. Any suggestions? Also, I was looking the new Ryzen 4000 laptop processors, which consume 15-45W and wondering if we can get motherboards with compatible socket in the market.

I asked this question before on stackoverflow but i got 0 replies and also a downvote. I hope someone could help me. First of all sorry for my bad English because i am from Germany. For generall infromations: node version 12.14.0 npm version 6.13.4 electron version 8.2.5 angular version 9.1.4 I have generated a Electron Angular App from this template and i added a button so that when i click the button the script trys to send files to ftp via a npm ftp package. The problem is none of the packages does work correct like it should. Packages i tried: ftp ftp-client basic-ftp The Problem i had with ftp: when i use this package i must click the button at least twice so that it connects and uploads the file. It should upload the file imidiatly but it doesnt. I tested a few things and found out that its becuase it times out after 10 seconds. But thats not the problem. The problem is that it never ever connects on the first attempt. I've tested it at least 30 times and it always times out at the first attempt. The Problem i had with basic-ftp: The problem here was that it connects directly at the first attempt but it takes like 10 seconds to connect to the ftp and then uploads the file in another 10 seconds or takes even longer. Also it just sometimes works on the first attempt. Sometimes i must click the button 5-10 times so it uploads the file. It logs a lot to the console if you follow the example code. But the log doesnt seem to have any errors or something it just doesnt go like it takes a nap and then wakes up again. The Problem i had with ftp-client: Here the problem is realy not complicated: it just doesnt work. Sometimes it gives me an "Error: Control connection timed out." after i hit the button 5 to 8 times and sometimes it just doesnt work. In every case i used the example code from every repository but just for reference here are the codes i used for the diffrent npm packages: ftp: var Client = require('ftp'); var fs = require('fs'); var c = new Client(); c.on('ready', function() { c.put('C:/test/test.txt', 'test.txt', function(err) { if (err) throw err; c.end(); }); }); // connect to localhost:21 as anonymous c.connect({host: "local.host.com", username: "username", password: "**********"}); ftp-client: const config = { host: 'local.host.com', port: 21, user: 'username', password: '*******' } var ftpClient = require('ftp-client'); var client = new ftpClient(config, {}); client.connect(function() { client.upload(["C:/test/test.txt"], './', { baseDir: 'test', overwrite: 'all' }, function(result) { console.log(result); }) }) basic-ftp: const ftp = require("basic-ftp") async function example() { const client = new ftp.Client() client.ftp.verbose = true try { await client.access({ host: "local.host.com", user: "username", password: "***********", secure: true }) console.log(await client.list()) await client.uploadFrom("C:/test/test.txt", "test.txt") } catch(err) { console.log(err) } client.close() } I realy hope anyone can help me. I realy dont know where the mistake is. I also didnt upload a realy big file it was just an .txt with "Hello World" in it. As you might have guessed the test.txt is located in "C:/test/test.txt" and also the domain "local.host.com" is just a placeholder.

I'm helping my sister to buy a laptop to be used for programming and video editing but I don't know which specs of the laptop to look for with these uses. Can anyone tell me which components or specs of the laptop I should look into for programming and video editing? Thanks!

Budget (including currency): less than $1500 Used for: Gaming and Programming Other details : Look doesn't matter

Code won't run in visual studio, but runs on online compilers for c++. Trying to make a program for myself to calculate credit Limits, just for fun. // Example program #include <iostream> #include <string> int main() { float balance = 0; float maxLimit = 0; float needToPay = 0; float desiredLimit = 0; //Balance Finder printf("Enter Your Balance, Max Credit Limit, and a percentage that is under 30. \n"); scanf("%f %f %f", &balance, &maxLimit, &desiredLimit); desiredLimit = desiredLimit / 100; printf("Your Balance is %f \n Your Max Credit Limit is %f \n Your Chosen Percentage is %f \n", balance, maxLimit, desiredLimit); needToPay = ((desiredLimit * maxLimit) - balance) * -1; desiredLimit = desiredLimit * 100; printf("To get your Balance to %f Percent, You would need to pay %f", desiredLimit, needToPay); return 0; }