Circuits Topics

Retiring the Forums

After more than a decade, Instructables has decided to retire our forums. This exclusively pertains to the "Community" section of this website where this topic is posted. Step-by-step instructable tutorials will not be affected in any way by this change.Starting in October we will no longer allow site members to post new forum topics in the Community section. The existing content will remain online and accessible through 2020 to provide everyone the opportunity to save any relevant information. In the spring of 2021, we plan to take the Community forums offline entirely.This decision was not made lightly. For many years we considered these pages the heart of the community. However, times have changed. It’s with some sadness that we need to acknowledge this and adapt.Our biggest clue that it was time to retire the forums came as our site traffic more-than-doubled over the last few months. We observed that the number of Instructables being published increased, the number of comments increased, the amount of favoriting increased, and just about every other measurable form of participation on this website also increased. The one notable thing that did not increase was the number of forum topics being published. We continued to receive, on average, about one a day.This forced us to look at some hard truths. The first is that the world has changed. In 2005 our forums offered a big tent to the maker community at a time when there were few places to go and interact socially with a cross-section of like-minded individuals. However, most of the conversations that used to happen here have now moved to either social media, Reddit, or niche forums elsewhere on the internet. No one builds general discussion forums like ours anymore, and most others have gone extinct a long time ago. The other hard truth we had to reconcile with is that fundamentally our core business is not running a forum. Nevertheless, we spend a lot of time keeping them up and running. For every valid forum topic that gets posted on the site, we get about 50 forum topics that get caught by our spam filter and end up having to be reviewed and deleted. In addition, the forums are based on some of the oldest code on our website, which means they tend to break often. Keeping them up and running distracts energy from our very small team that could be better used elsewhere. That said, there are now more places than ever that you can go to discuss making online. For starters, you could connect with us on Twitter or Instagram where we have a thriving community. You should also check out some of these awesome staff-recommended channels and sites: thank everyone for all of their contributions to these forums over the years and the community you helped make flourish. We welcome everyone to share your thoughts, feelings, or memories below.

Topic by randofo    |  last reply

Welcome to Instructables

On this page you can find links to some of our most frequently asked questions. What is this site? Instructables is a community for people who like to make things. Our community shares what they make in a step-by-step format that we call an Instructable.How do I post an Instructable? We offer a free and easy online class to coach you through posting your first Instructable or you can just wing it and start a new one today. How do I get help improving my Instructable?Ask the community for help in The Clinic. How does my Instructable get featured? The best way to get your projects featured is by following the Featuring Guidelines. Where can I learn more about contests? Our Contest FAQ has all of the information that you need to know about contests. What contests are launching soon? Check out our list of upcoming contests. Are you on social media? Yes! Follow us on Pinterest, Instagram and Twitter. How do I contact Instructables directly? The best way to contact us is through our Contact Page.

Topic by randofo    |  last reply

List of Upcoming Contests (updated 6/29/20)

Hello everyone! Below is a list of the upcoming 2020 contests. Keep in mind that this list is subject to change and contests will continue to be added throughout the year. The contests below are in planning, and I've left off ones that we're still trying to decide on. The months indicate when the contests will be launching. Keep in mind that the list below is not set in stone. All contests and dates are subject to change!JulyFrozen Treats Speed Challenge: Make a treat that's frozen. July 6Secret Compartment Challenge: Make a project related to hiding spaces. July 20Lighting Challenge: Use lights in your project. July 20CNC Contest: Use or create computer-numerically-controlled machines. July 20Robots Contest: Make a robot, use a robot, turn yourself into a robot, etc. July 20Make it Fly Speed Challenge: Send something through the air, controlled or uncontrolled! July 20AugustPuzzles Speed Challenge: Make a puzzle. August 3Back to School / Distance Learning. All things related to back to school and/or distance learning. August 3Sandwich Challenge: Make a great sandwich, share your secret process and ingredients, etc. August 17Stone, Concrete, Cement Challenge: Use any or all of these materials in your project. August 17Build a Tool Contest: Build a tool. August 17Make it Move Contest. If there's movement in your project, it's eligible. August 17Glass Speed Challenge: Use glass in your project, but don't cut yourself. August 17Recycled Speed Challenge: Use recycled materials to make something awesome. August 31SeptemberBikes Challenge: All projects related to bikes. 14 SeptemberPumpkin Challenge: All projects related to pumpkins. Go traditional, or go way off the beaten path. September 14Halloween Contest: Our classic yearly contest, for all things Halloweeny! September 14Remix Contest: Remake and improve an existing project idea, whether your own or someone else's. September 14Mason Jar Speed Challenge: Use a mason jar in your project. September 14Potato Speed Challenge: Open to all things potato. September 28 *All contests and dates are subject to change. Please leave suggestions for prizes here. You can also leave suggestions about contests here. Have a contest question? Check the Contest FAQ!

Topic by randofo    |  last reply

Is there any way I can reverse engineer the wiring for this car CD player? Answered

I have a 2001 Nissan Maxima that I intend to customize just a little (well, a lot).  Recently I was at a garage sale and bought a 6 disk CD changer for $1.  I'm hoping this was a worthy investment since I want to install it in my glove compartment and wire it into a custom stereo system.  That's all fine and dandy, but step one is to figure out how to reverse engineer the proprietary control systems.  Eventually I want the air condititioning, stereo, and this 6 disk CD changer to be interfaced to a computer with a big ole touchscreen in the dash.  I'm going to need to do a few things: 1. Figure out the wiring for the 6 disk CD changer so that I can power it up, control it through the computer, and connect it's audio output to my car's speakers.  2. Figure out the wiring for the air conditioner so I can control it with the computer. 3. Get a touch screen that fits in the dash (I'll measure it later), that I can use with a computer with (relative) ease.  These are my goals for right now.  If I can figure this out, I will be ready for the next phase, actually installing the new dash.  If anyone can recommend any sources to learn more about basic car work, that'd be helpful too.  I'm used to computers.  The lid comes off.  Screws are all easily accessible.  Parts don't weigh more than I do.  I know where everything goes and what everything does inside.  Since a car is so proprietary, and such a new field for me to be working in, ANY resources would be greatly appreciated.  How do I figure out how to take things apart in my car?  FYI: The disk changer is marked with part number 39115-s3v-a011-m1 Update (18 August 2012): I added some pictures.  The connector I am holding is the only connector that comes out of the box. 

Question by meztek    |  last reply

Building BCI

Hi folks!I am 16, and I want to build a BCI that the paralyzed use for controlling a robot. I have watched the most courses series on YouTube. But I still feel lost and I don't know where to start. I want the project to end up successfully. Ie when the user wears a headset and he/she wants to drink, the robot gives them water and so on. What kind of brain signals should I use. What steps should I take in order. I don't want the project to take years. I wand to end it as soon as possible.Thanks!!

Question by Sarah20201  

4p 18650 power backup using TP4056's with protection

Hi Everybody, I need help with project I am up to so any advices would be much appreciated. Setup: Laptop power supply 20V 3A 4x TP4056 with protection 4x 18650 lion cells of different condition 4x P-MOSFET 4x Schotky diode 4x 1k resistor 1x step down module 1x step up module Task: Want to build 18650 cell charger (backup power supply) using 20V power supply and charging circuit with TP4056 in parallel. Goal: Should be able to run constantly connected to main power supply being able to simultaneously charge the cells (and cut them of while fully charged) and supplying power to the load. For the input I plan to use step down convertor to get 5V (for parallel connected TP4056 chargers) and for output step up convertor to get 12V for the load. I did a lot of research already, therefore I incorporate P-MOSFET, Diode and 1K resistor to not to disturb the precision of the charger and prevent the drain of the cells once charged. I also draw the circuit how I think it should be done. I am new to this so I will appreciate any input, correction or alternative to this. Whole idea is to be able to charge cells which are unmatched without balancer and being safe. I am not sure if the TP4056 protection would serve sufficiently for this. Also am interested how much would be maximal possible current output. Plan to use Samsung IRC18650 14b cells at the moment which I salvaged from my old laptop battery.

Question by pavelkryml  

Mouse mods question

Hi there, I have a question regarding the connection port inside the mouse (Dell). It shows d+(green wire), d-(white wire) , s(black wire), v(red wire), and g (empty no wire). See attached photo. I'm trying to add a timer to it and I need to add a wire to the v(red wire) and a wire to the ground, but my question is there is no wire that currently goes to the ground inside the mouse so where to I add my ground wire? In the empty slot? Or to the s(black wire, usually the ground) is it considered to be the ground? What does s(black wire) mean? Thank u for ur time

Question by sanchezas  

Low voltage, high amperage transformer?

Hi! I would like to make, buy, or find, a low voltage high amperage transformer to power an electrolosis cell. I like playing with the hydrogen-oxygen gas produced. From what I have read, I only need about 1.8 volts for electrolosis, so I'd like a circuit or transformer that could take the power from preferable a 9 volt battery and convert it to 1.8v at as high an amperage as I can get. Thanks : )

Question by fozzy13    |  last reply

Contest FAQ (Frequently Asked Questions)

Here at Instructables we run a ton of contests! We also get asked a ton of questions about those contests. Below is a list of the contest questions we get asked most frequently and also some questions that we feel could use a little more explaining. (Let’s be honest - reading the official rules is not fun.)Please ask addition questions in this forum topic - I'm sure there are some we have not covered!Important links: List of upcoming contestsContest suggestionsPrize suggestions General Contest Questions How do you choose which contests to run?We do this in a few different ways.Contests are planned based on past contest themes, what’s trending in search, which categories/channels need a little love, new site features or if there’s a certain type of content we want. Contest ideas also come from staff meetings and through the official contest idea forum topic.I have an idea for a contest! How do I tell you guys?Please post here and let us know! We can’t run all of them, but we love seeing the ideas you guys come up with. How do I win a contest?Post something awesome! Check out this collection of tutorials that will tell you how to write a great instructable. Why do Instructables employees enter the contests?We enter contests to set the bar and give an example of the type of entries we want in the contests. We're not able to win them, though!It's important to note that several employees were authors on the site before they worked here, though, so you might see some wins in our achievements! :) Entering Contests Can I enter if my country is not listed in the official rules?Yes! You can definitely enter.However, you must have a mailing address in an eligible country to win. If you have a friend in the US or another eligible country that can receive your prize, go ahead and enter!You can read more about our progress to add more countries to the eligible shipping locations here. I live in -----, why can't I enter?!Chances are your country has incredibly strict laws regarding gambling, sweepstakes and contests. We try our best to play by the rules, and if we can't meet the minimum requirements to run a contest in your country, we don't run them there!That's the easy answer. The hard answer is that it's very complicated and involves lots of risk and scary legal language. Why isn't my entry showing up in the contest? I entered three minutes ago!Real humans look at each entry! This means it take take a while sometimes. We work standard office hours, 9-5ish PST. We tend to moderate first thing in the morning, Monday-Friday.If you enter at the end of the work day or over the weekend, you may have to wait until the next business day to be accepted. Why can I only enter one contest with one Instructable?It’s all the spirit of fairness. In the past, we've had popular instructables sweep multiple contests with huge wins. This new rule will allow more authors to win! Why was I rejected from the contest?The number one reason for this is not fitting the contest theme - we try our best to explain the sorts of entries we’re looking for on the main page of each contest, so double check your eligibility there.We also sometimes make mistakes or encounter bugs during the approval/denial process. (Checking the wrong box, clicking the wrong button, breaking the back end of the site) It’s rare, but it happens! We’re human and can’t help it, but we do our best to right those mistakes as soon as we know they happened! Why can’t I enter an instructable I published before the start date into the contest?We want to see NEW and exciting content built just for the contest. If we allowed old instructables in, we’d just see the same things over and over again. Plus, the number entries in the contests would make it very hard to choose finalists and winners.Keep in mind that simply republishing an old project will not make it eligible - we check for that. ;) Can I edit my Instructable after it's entered in a contest?Short answer: YES!Long answer: You can make any modifications you want to an Instructable that's already entered! We get so many entries that there's absolutely no way we'd be able to police it even if we wanted to - but it's never something we want to discourage.Improvement is always a good thing as far as I'm concerned. :)However, we must caution you: it's best to get those changes done before voting closes. The voting period matters the most because that's the time that we start looking into picking finalists.Another slightly related caveat: don't publish a mostly empty instructable and try to fill it after the contest ends. We're starting to see this happen more often, always with a promise that updates are coming. You can never tell when we'll be reviewing it as a possible finalist, so chances are you'll get overlooked going about it that way. We are currently looking at 50-300 entries per contest, so anything incomplete doesn't stand a chance these days! Finalist & Winner Selection When are the finalists selected?Finalists are selected starting the Tuesday after the contest closes. The finalist selection process normally ends Thursday of the same week, depending on how tricky the contest is and how many people give input. How are finalists selected?Finalists are selected by site staff based on the following criteria: clarity, ingenuity, creativity, quality of presentation, and execution of the Instructable (as noted in each contests' official rules section). You can make your instructable stand out further by including the following: Good photos! Pretty photos put you five steps ahead of all the other entries already, honestly. We're going to want to click through and look at it as soon as we see it if it's pretty! Good explanation of both WHAT the project is and HOW you made it. Sometimes it can be really hard to figure out what we're looking at. (Personally, if I have to spend several minutes staring at photos and reading to understand it, I'm not very excited about it anymore.) Try to convey the project through both photos and video if it's needed. For example - if it's a rocket, upload a video of it in action! A good story! I read more projects than you could ever imagine every month. I love it when an author takes time to explain why they made the project, or documents the errors they made along the way. That makes an instructable so much more enjoyable to read. :) Citing your sources/inspirations - look, we realize there's hardly an original idea on the internets anymore, so we can't fault you for that. But it's only fair to give credit where credit is due. We like that. Plus, it sometimes makes for an awesome story. Creativity! Look, I cannot even begin to tell you how many paracord bracelets, Altoid tin survival kits and Iron Man arc reactors I have looked at. My eyes glaze at the thought. Don't just go for the common and easy, take that project and put a new spin on it!!Relation to prize. In some contests, we offer a Judges Prize. Entries that qualify for this prize are also taken into consideration. We always suggest authors read their own work with an objective eye. Does it make sense if you aren’t familiar with the subject already? Did you provide enough description? Are the photos understandable? How many finalists are there?To find this out easily, go to the contest page and look at the total number of prizes to be awarded. The number of finalists for a given contest will match the number of total prizes. Why wasn't my project chosen as a winner/finalist?This can happen for all kinds of reasons, honestly. See the "How are finalists selected?" question above for a more in depth explanation of what we're looking for.The most important thing to stress is that we are going through TONS of entries for every contest, so it's important to set yourself apart. Choose a clear and concise title, tell us a story, share great photos, explain the project well. If there are projects similar to yours in the contest already, make sure your project exceeds theirs in awesomeness. Also remember that competition is fierce in the contests - there are always a LOT of amazing entries. When it comes down to selecting winners sometimes it's the little things because when you're comparing awesome to awesome the little things are all you can look at. So be detailed orientated when writing your instructable. Judging Who judges the contests?This is typically a mix of Instructables staff and authors on the site (your peers!). Each contest is normally assigned 10-50 judges.Lately we’ve had an average of 15-20 judges complete the process. I always try to add as many judges as possible, because more judges means the judging is more fair and helps to reduce bias. How can I help judge a contest?If you’re interested in helping us judge, check out this forum topic! To judge, you must have published at least one Instructable.We send out PMs to judges on the Friday after a contest closes. How do I judge a contest/access the judging ballot?We’ve written up an Instructable over it! You can find it here: you're added to the list of judges, you’ll be able to access the ballot. Prizes How do you pick prizes? Can I suggest prizes?We've got a pretty small budget prize here, so it's a mix of trying to be frugal but still give you guys something fancy. We try to order most of our prizes from because they have reliable shipping and tons of options.If you'd like to suggest an awesome prize, do it here! I don't like these prizes, can I trade?Short answer: nope!Long answer: we choose prizes well ahead of time and order prizes at the start of the contest (for 95% of what we run) and we don’t make substitutions. We typically have anywhere from 100-250 winners a month (and increasing all the time!), so it’s not feasible to give choices and sub things out. Only three of us on staff work with ordering the prizes and shipping them out, so that would be lots of work!However, we have allowed winners to switch prizes with another winner on occasion (both parties must agree and let us know before we ship them!) and we’re fine with you selling your prize somewhere else. How do I get my prize if I win?When contest winners are announced, we’ll send you a message with a form to fill out. Make sure to fill this out completely and remember that we require a phone number and that we can’t ship to P.O. boxes.Winners are responsible for any trade tax or tariffs incurred for shipping to your location. We cannot reduce the value of the prize so you pay less tax (nice try, though, you sneaky hobbit!!). When will my prize ship?We try to ship prizes as soon as possible! 75% of our contests have prizes that are easily shipped right away and you should receive notification of shipment within a week or so.Sometimes we do have to order items AFTER the contest ends or wait for a sponsor to ship the items. If we think there will be a delay, we’ll let the winners know. We’ve been trying very hard to make sure we’re reaching out and updating winners about prize statuses.Also: VERY IMPORTANT - the sooner all winners give us their contact info, the sooner we can make big orders of custom sizes. Sometimes there’s a huge delay just because we’ve got one straggler. Be a good winner and let us give you prizes, dangit!!

Topic by jessyratfink    |  last reply

What kinds of contests do YOU want to see on Instructables?

Hi everyone! As we're planning contests for the next year, we wanted to get suggestions and feedback on the types of contests we're running. :DIs there a contest we ran years ago you'd like to see again? Any contests you're sick of? A weekly challenge you'd like us to expand on? Do you want the contests to be more specific or more open ended?We're trying to shake things up in contest-land - so any and all suggestions are welcome! I'm especially interested in what types of tech contests you guys would like to see, as well as ideas for food contests. P.S. For anyone wondering about weekly challenges - we're still trying to figure out a way to do it that makes it easy for you guys to enter and easy for the editors here to run. But I promise we are discussing it! :)Have prize suggestions? Check this topic. Want to get a preview of some of our upcoming contests?

Topic by randofo    |  last reply

How to program IC v9881d to make energy meter (KWH)?

I want to make a single phase electrical energy measurement module using IC V9881D. After learning a little about the IC, it turned out that the IC had to be programmed before it could be used. I don't know how to program the IC. Does anyone know how to program the V9881D IC so that it can produce voltage (Volts), current (Amperes), power (Watts), and single-phase electrical energy (Kwh)?

Question by de ap    |  last reply

Where to get piezo igniters?

I have several lighters that I still like, either for their design or intended purpose. But over the years some failed to produce proper sparks with the piezo. For some I could salvage replacements from cheap lighters but not so much for the longer ones - the type to get your bbq or oven going. Here the wire from the igniter is in ne long piece going all the way from the piezo, through the long neck to the flame outlet. As the wires in those piezo igniters are aluminium it is next to impossible to attach a longer wire as usually there is no room for crimped connections and the isolation is a problem too. I also have one particular lighter that uses a slightly longer and thicker piezo igniter, the common ones don't work here as they are too short. Adding more support underneath is a no go as the shorter ones have less travel when activated. Last but not least is one lighter that requires a piezo with not just the little metal cap at the end but with a full metal body for the stationary part. The lighter in question does not work with standard types even if I add a little metal strip to make proper contact. Problem is simply put that like this the standard ones arch over and no spark comes out of the wire. So big question: Is there any supplier or Ebay shop where one could actuall see the various types of piezo igniters and order them in small or single quantities? So far I already struggled to find a source for the crappy standard ones and the only one I found wanted to charge $ 2.95 US per igniter plus postage. Sounded a bit greedy to me considering I can buy a complete lighter with it for around one single buck...

Question by Downunder35m    |  last reply

Ventilator sensors

Hi guys It's for a ventilator (open source ) project So I want to modify some stuff & Kinda upgrading the app So my probleme are in sensors ( pressure sensor , airflow sensor) For the pressure sensor I decide to take this one: The range of pressure needed(0- 5 pka) is fine (0-40 pka) But the problem is the airflow sensor.. (0- 20/25L/MN) I thinker about water flow sensor (0-30L/MN) {YF-S201} That's will be work??? If no please give me some advice or , kinda of sensor that I can use for measuring the airflow The porpus of all that it's to make an graphic , like monitoring of the ventilator Best regards

Question by Snake00012    |  last reply

how to hack school laptops?

the msn messenger on the school laptop dont work cause dey blocked everything in it so how can i make it work?

Question by lebo1    |  last reply

Forums are retiring - I am building a replacement-forum

OK... As many of you may have heard, the forums here @ Instructables are closing permanently this october. See may have its cause and it is all explained in the linked post. I want to thank the instructables-Team to have provided such a great community over all these years. I learned a lot and enjoyed reading all those posts and answering those questions asked. I may even have had a positive influence on someones live. Who knows?Anyway: I dont aggree with the result of the analysis that there is a falling # of posts and activity in the forums here. I think it was more a self-killing system with bad & old Forum-software not motivating for new users and new posts. This in return gives low activity and low incentive for staff to update the forum and make it more appealing. Less appealing forum = low user-acitvity = low staff-incentive = Less appealing forum = ...I still think there is a big benefit for a dedicated forum for DIY and instructables. But ranting does help nobody. It is a free world and Instructables / Autodesk have made the decision. OK. Lets see what we can do from here on.I quickly grabbed a Domain, booked a webhosting and set up a rudimentary phpBB.-->> <<--Currently, userregistration is disabled. If you want to help out, please dont hsitate to contact me here om Instructables via PM. Soon we will have the structure and details and rules fleshed out and will be opening the gates.Someone has a nice idea for a logo?

Topic by Orngrimm    |  last reply

The Clinic // Get help with your Instructables!

Hello and welcome to the newest version of The Clinic! If you have an instructable that's not getting the attention you think it deserves, post it in the comments below for honest feedback and suggestions to improve it from fellow authors and Instructables staff. We want to help you create the best instructables you can! Curious about the basics of creating an instructable? Check out my FREE How to Write an Instructable Class! You can also read through our Featuring Checklist. Posting a great instructable has many benefits, including:More viewsMore comments and followersHaving your instructable Featured on the site Having your instructable featured on our social media accounts (Facebook, Instagram, Twitter, Pinterest)Better chance to win contests Driving traffic to your websiteP.S. While I know the goal for any instructable is to get Featured, it's not the end goal here! We're sure to hand out features, but please keep in mind not every instructable is feature-worthy. Even the most popular authors have unfeatured instructables! Don't let it get you down - you're still amazing! :D

Topic by jessyratfink    |  last reply


Hello. I try to program an Arduino-sketch for cars and pedestrians. I have already made a begin to this sketch but there is an error in it.The sketch is attached to this topic. In line 16, the 'sensorValue' is not decleared. As i am a beginning programmer, i have not found a solotion yet. Ho can tell me what to give in to this sketch to make it run?Already thanks for answers.

Topic by pascaljansen1    |  last reply

connect usb cable to usb keyboard

I have a usb keyboard. somehow the usb cable is disconnected from the keyboard. I opened the keyboard. USB cable has 4 wires (1 blue, 1 orange, 1 white and 1 green). The circuit board has code like C, V, D and G. Now which one is for which wire? out of C,V,D and G which is for ground, which is for VCC and which is for Data+ and data- the color code of USB cable I know. But cannot understand which wire to connect which code (C,V,D,G) of circuit board?

Question by jpsarkar    |  last reply

Stylus digitizer suggestions for diy drafting table?

I want to build a drafting table with a glass table top and a screen behind it. That way I can do things like:1) display reference images while I work on art2) trace things from screen onto paper3) toggle the screen to 100% white and use as a backlight4) draw shapes using traditional drafting tools and have them digitized. (Think of using triangles, compasses, and whatnot to draw on a Wacom Cintiq)It's that last thing that has me scratching my head. What are some affordable options for a fairly large screen with stylus (and possibly touch) capabilities?Will it work behind thick tempered glass?Should I / can I make my own digitizer?

Question by PS118    |  last reply

Need help Arduino DC motor

Hi guys , I need your help How to build a diagram & Arduino program to control a DC motor (9v I think) datasheet required & The program from the Arduino to Run the motor for 3 second (clockwise)stopping for 2 second & finally turn for 3 second in the other sens All that is a cyclic mode (8 seconds) at all Thanks

Question by Snake00012    |  last reply

Need help for Arduino Project based on Covid

Hello good people,I am trying to make an Arduino Project which can measure Body Temperature, Heart Rate & SpO2 using MLX90614, VL53L0X & MAXREFDES117# sensors respectively with Arduino UnoFor Heartrate and SpO2 output i am using program and algorithm modifies by RF Master whose github link is Temperature measurement i am using MAX90614 with LV53L0X LIDAR sensor for range monitoring.For the above combined output i am using ADAFRUIT libraries. And i am getting desired output from both these sensor when combined together in a program.My problem is that when i combine them all i dont get a output., the programe runs to certain extent then stopsFor simplicity i am attaching the library for MAXREFDES117# and the main program that i have modified and the output data.Your help will be very much appreciated, i have a mechanical engineering background with basic logic of programming. RegardsShubhashishProgram 1: where i take input from the user#include #include #include #include "algorithm_by_RF.h" #include "max30102.h" #include #include Adafruit_MLX90614 mlx = Adafruit_MLX90614(); VL53L0X sensor; const byte oxiInt = 10; uint32_t elapsedTime,timeStart; uint32_t aun_ir_buffer[BUFFER_SIZE]; uint32_t aun_red_buffer[BUFFER_SIZE]; float old_n_spo2; uint8_t uch_dummy,k; bool hr=true; uint8_t ip = 0; void setup() { Serial.begin(115200); Serial.println(F("1. Heart Rate\n2. Temp")); while(Serial.available()==0) //wait until user presses a key ip = Serial.parseInt(); if(ip==1) {hr = true;} else {hr=false;} if(hr) { pinMode(oxiInt, INPUT); Wire.begin(); maxim_max30102_reset(); delay(1000); maxim_max30102_read_reg(REG_INTR_STATUS_1,&uch;_dummy); //Reads/clears the interrupt status register maxim_max30102_init(); //initialize the MAX30102 old_n_spo2=0.0; } else { mlx.begin(); Wire.begin(); sensor.setTimeout(500); if (!sensor.init()) { Serial.println("Failed to detect and initialize sensor!"); while (1) {} } sensor.setMeasurementTimingBudget(200000); Serial.print(sensor.readRangeSingleMillimeters()); Serial.print(F("*F\tObject = ")); Serial.print(mlx.readObjectTempF());Serial.println(F("*F")); if (sensor.timeoutOccurred()) { Serial.print(" TIMEOUT"); } delay(100); } if(hr) {; Serial.print(F("Time[s]\tSpO2\tHR\tClock\tRatio\tCorr\t")); timeStart=millis(); } } void loop() { if(hr) { float n_spo2,ratio,correl; int8_t ch_spo2_valid; int32_t n_heart_rate; int8_t ch_hr_valid; int32_t i; char hr_str[10]; delay(1000); for(i=0;i Output for this program when user selects Heart Rate1. Heart Rate 2. Temp Time[s] SpO2 HR Clock Ratio Corr 0 737 508 1 731 511 2 733 507 3 734 506 4 728 504 5 734 506 6 738 503 7 736 505 8 731 507 9 741 503 10 739 516 11 733 508 12 734 512 13 735 507 14 730 507 15 732 494 16 741 502 17 734 509 18 728 502 19 742 505 20 742 500 21 736 502 22 742 501 23 734 508 24 735 508 25 733 506 26 734 505 27 732 507 28 732 498 29 737 505 30 736 504 31 729 502 32 731 498 33 730 502 34 733 507 35 730 502 36 730 508 37 729 504 38 729 505 39 731 505 40 730 500 41 731 497 42 733 498 43 733 505 44 736 504 45 730 501 46 731 505 47 733 506 48 734 505 49 732 498 50 735 502 51 736 499 52 731 499 53 729 507 54 729 506 55 728 504 56 734 499 57 729 509 58 734 503 59 727 507 60 736 501 61 730 505 62 735 501 63 734 507 64 731 508 65 732 503 66 731 503 67 736 506 68 731 502 69 738 512 70 736 506 71 734 504 72 735 505 73 733 506 74 733 503 75 730 506 76 730 502 77 732 508 78 731 502 79 734 508 80 733 505 81 727 504 82 742 508 83 735 506 84 738 503 85 729 504 86 729 505 87 728 502 88 726 512 89 729 502 90 734 503 91 737 499 92 732 510 93 739 503 94 734 512 95 731 510 96 734 499 97 738 503 98 729 505 99 724 510 03 734 512 731 510 734 499 AA1. Heart Rate 2. TempOutput for this program when user selects Temp1. Heart Rate 2. Temp 70*F Object = 85.26*FIf i comment out the code which take input from user then i get ouput based on condistion bool hr=true or bool hr= false#include #include #include #include "algorithm_by_RF.h" #include "max30102.h" #include #include Adafruit_MLX90614 mlx = Adafruit_MLX90614(); VL53L0X sensor; const byte oxiInt = 10; uint32_t elapsedTime,timeStart; uint32_t aun_ir_buffer[BUFFER_SIZE]; uint32_t aun_red_buffer[BUFFER_SIZE]; float old_n_spo2; uint8_t uch_dummy,k; bool hr=false; //uint8_t ip = 0; void setup() { Serial.begin(115200); //Serial.println(F("1. Heart Rate\n2. Temp")); /*while(Serial.available()==0) //wait until user presses a key { ip = Serial.parseInt(); } if(ip==1) {hr = true;}*/ if(hr) { pinMode(oxiInt, INPUT); Wire.begin(); maxim_max30102_reset(); delay(1000); maxim_max30102_read_reg(REG_INTR_STATUS_1,&uch;_dummy); //Reads/clears the interrupt status register maxim_max30102_init(); //initialize the MAX30102 old_n_spo2=0.0; } else { mlx.begin(); Wire.begin(); sensor.setTimeout(500); if (!sensor.init()) { Serial.println("Failed to detect and initialize sensor!"); while (1) {} } sensor.setMeasurementTimingBudget(200000); } if(hr) {; Serial.print(F("Time[s]\tSpO2\tHR\tClock\tRatio\tCorr\t")); timeStart=millis(); } } void loop() { if(hr) { float n_spo2,ratio,correl; int8_t ch_spo2_valid; int32_t n_heart_rate; int8_t ch_hr_valid; int32_t i; char hr_str[10]; delay(1000); for(i=0;i

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Contest Judges Needed

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