arduino 7 day timer
We make a countdown timer, because a viewer asked us to right. After this you, you ting the new way. Everyone is getting their cell service, no overage penalties, great rates, keep what you do not use no contracts and someone will actually pick up the phone when you need support, use our link and get 25 off your first month service or your new phone just go to Tech send TV, ting, hello, it’s time for another let’s make it, and this week we actually skipped the week and if you were watching live this week, I’m sorry, I was actually out sick. I probably could have done a show, but we’ve been coughing couple times a minute understand, thinking to be very productive and nobody else really underly either, and I wasn’t really feeling good actually kinda hear my voice is still kind of scratchy I’m still getting better, but I Feel a lot better, just my voice in my throat and drainage until I get still going on, but we didn’t do a show last week also bob is in the middle of moving so I’m, assuming he’s still moving, and Bob good luck with that, because I sent Him an email today and didn’t hear anything back which tells me knowing how Bob responds to the emails. He is busy doing something, and I imagine he still in the middle of his move. I know because that’s gon na take a week or two to get everything moved so it’s.
I wish Bob good luck during his move this week. So this week is episode, number 42 and it’s recorded on November 4th 2013 and I actually had a little bit of a hard time figuring to do this week. I had some things planned, but I haven’t had much time the last two weeks because a lot of changes going on in here. In fact tonight I was scrambling to get everything back up because I’m moving some of my sub office software switching from a Mac to a PC, so I have a better expansion and in that process today it didn’t work right. So I ended up punting and going back to the old system and I’m having licensing issues, in fact on the stream. For some reason, Wirecast is no longer licensed on that machine. So whatever the reason is going on with that. But we are here tonight and we do have something to talk about, but this week’s show actually did today because I got an email from somebody asking about a countdown timer. So we’re going to talk about all the countdown timer. The features that he wanted and we’re going to walk through the code and hopefully that helps him out, but I do want to apologize. I got a lot people in front of here that are starter because I have them followed up with, I know Andy. Has it Fink was had some questions for Bob, and I, and I know I haven’t had a chance to respond to him.
I don’t know if Bob’s had a chance being a little of his move. Sorry, we will get to that. These people are off your star. You’Re going to get response back, I just haven’t gotten around to it yet also the ghost can’t was a different question unless relate to this show we have zero LCD from Gennaro, and then we have Colin has about the ZB project. So we have all these things in my queue here that I will respond back. It just sounds to me a little bit in these last few weeks, basically tearing apart the studio, moving everything around and trying to put it back together. I have been taxing not to mention getting sick on top of all that, so very sorry, for all these delays, as winter starts setting in and week everything kind of set on the studio, I think you know weather being not so warm will be inside a lot More and be able to a little more focused okay. So this reminder we do have a chat room. If you want to come and chat, it is a Texan TV, slash Lodge, you can watch and chat live in there all the time, and if you could youtube.comsetsailtv, you can see all of our old shows they’re out there on YouTube. In addition to being locks you on our website, if you go to text n dot TV, so you can subscribe on YouTube or if you want to get it automatically downloaded, you can subscribe anymore, dog, catcher or iTunes.
Wherever you do the kit, your podcast from I wish you be there and if you don’t, find us in your favorite location, please let us know we’ll make sure we get ourselves listed out there. If you are on Twitter, you can follow us at xn TV. In fact, if you fall some tags n TV last week, we tweeted that we wouldn’t be doing the show, because I was sick and if we can, you can get updates. So you don’t show up with it in the live area and dot. Don’T have anything there. So if you want to check out this show in Twitter use the hashtag let’s, make it pounced on let’s, make it and that we do follow that and try to respond back to that now. Something else is also using the pound. Sign let’s make it. So we are waiting through that stuff and at some point we may decide to change that because of the other people that are using that already. But well, we didn’t realize that until we started using it and if you’re on Facebook we’d love for you to give us a thumbs up, it’s facebook.com, slash tech, zen TV, alright, so this week’s would be a fairly straight week because I really only have one thing To show you and I’m going to go over and let me show you what I have here on the table. So what I have here is a keypad which came from another episode of the episode 11, and so our our Irena cut some of that code, and then I have a I to see LCD, so it’s, a four by twenty LCD and then right here.
All I have is an LED, so you guys use this Tyler breadboard and you see an LED and a resistor, and this is just to represent what a relay would be. So when the LED is on the relay would be closed, and this is part of an email that I got and I got this email yesterday or today, and I said this would be a great project for for a show. So basically, what it is is this is supposed to be like an exposure time or a countdown time, or so what you’re seeing it’s asking you to enter the time in minutes or seconds so I’m going to editor in this 10 seconds. Just to give you an example, so you see there’s one and then there’s zero and then to start the countdown you get pal and key right here and the clear clear you hit this once I’m going to clear it see we’re back to zero, so I’m, going Up at 10 seconds back and again and then I’m going to hit the pound and you’re going to see there really turns on, and you see it counts down, it’s going to count down to zero and it’s going to turn the relay off and it’s going to Go back and want to know how much time go again. Now ten seconds is going to be the right default. If you want to clear the eyes you get star, the other thing I did is I made this a rotating number, so let’s say you have already had 10 seconds in there and you want to go one minute next time you can just enter another zero or, If you want to zero the whole thing out and put it in on the number let’s say you had four minutes in there and now you want to do two minutes.
You can just do two: zero, zero and there’s your two minutes, so you don’t have to clear that if you don’t want to rotate the numbers out at that point, you can get powned and it’ll go ahead and run the timer again. I also built in an exit so condition to clearing. If you hit the star key or the asterisk, it will clear it out in the middle timer. So from my understanding of the requirements of the project for the values this would be used to. I do some kind of exposure control, so he asked you to be putting in minutes and then seconds, which is what this is doing. In that pound go and install were clear. He didn’t say that he wanted to be able to cancel out of it, but I figured if you’re gon na, if you want to get out of the timer you get out of it somehow. So what I’m going to do is I’m going to go and walk through some of this code with you assuming the switching works and it did okay, oh there, it is okay, so let’s get down past the comments here, get back over to my monitor and scroll Down here a little bit so well, you know to the very top is we have to include wired on H in the crystal because we’re using the LCD display – and this is dustman we’ve – used in quite a few projects, and I think we actually talked about, though The one the two wire interface episode, five or six pretty early on, we did LCDs very early on and then in episode, 11.
We did this keypad, so here’s keypad h. If you go back and look at that that project, so you see right here, I’m taking parts of the different projects which is not a bad thing, I mean we do, is a lot. You start putting up a library of functions. You just go back to them and copy the function. So, as you do more and more development, you big it faster and faster at it, because you can go back to all projects and pull pieces out of each project which is kind of what I did here. So I set up control pin 13, so I mean did that because I wasn’t sure I was going to use an LED at first. I just use the LED on the board, but then it wasn’t big enough indicator, so I went ahead. Add an LED, but I using pin 13 you can use any pin. You want probably something better than 13 bit 12, so you don’t have to have the LED on the board activated. Then I define a character array that holds the current time value, and this is the numbers you’re typing in so I store those numbers as four numbers, assuming that the first two are minutes in the second two are seconds, then I just take a call to moving The one I display it will show you that on down here, so as you type in you’re, basically filling in from right to left into these four character array and then here’s our state, our state engine.
So we talked about two engines before again we’re going to get through something we talked about in the past and that’s the state table or state engine, and then the timer seconds is the number of seconds for countdown. So this will count from whatever it is down to zero and when it turns to zero everything turns off and goes back to normal, and the way I did timing in this is probably not the best way to do timing. However, I think for this particular example, it was a simplest one to demonstrate what I like to do in the future. Maybe have Bob come one he’s very good, with timers in an Arduino much better than I am, and maybe do a segment on how to use timers in the Arduino. I could have used timer and probably have been a little more accurate. However, I think this is probably accurate enough for what is this.what to be doing all right. We come down. We define the keypad. We have in this particular four rows and four columns in the email he suggested he’s going to use a 12 button, which is three columns by four rows, and I just don’t have one of those. So I used one that has ABC and D on it but I’m, not going to use those ABC and D s for this project. Okay, so I set up the pins for the rows and the pins are for the rows is 11, 10, 9 and 8 and then they’re for the columns with 7, 6, 5 and 4.
And you may wonder why. I did it backward like this. And if you look at the wiring on the actual the keypad, these are in order. So if I 11 is, though, is the leftmost pin 10 is the second pin and on down the line, so it makes it nice and easy and clean to run the wires over that’s. The reason I did it this direction. These could be anything that you want. It to be alright, we define our keypad and we give that our keys at the top our row and column pins and the number of rows and columns, which is new, four by four start up our LCD and then we come in and we’re going to knit The LCD turn on the backlight and then we’re going to display the code entry screen. Now this really is the time entry screen. I should rename this guts up to soar. Another program at we need it, but what we’re going to do is display the welcome you know the weather let’s, make it count down time and then enter time and then mm SS. The this ready here does I go ahead and neutralize our pin for the relay, and I set the output and I turn it low because you don’t want to come on by default. You wan na make sure is turned off and then I basically erase the valve the time, values and zeros in there, so that something’s in there and then I showed the enter time which puts up the time on the bottom and risk it’s going to display by Default, zero, zero, colon, zero zero and we go back over here and you look at this – you can see right here – is the zero zero colon, zero, zero, so I’m, just basically blanking that screen out, so that it is at a good place, and then we get Rid of this okay, so we come on down here now we enter the loop and we define an integer for as an L.
We need a little later on here and then we define our temp value and you’re going to see how you just shortly, it’s how I determine the number of seconds parlor calculation to do that. I go ahead and get a key from the keypad pair. If one exists and if the key is not equal to 0, which means that key was pressed and I’m in state number one, which is the default startup state I’m, going to come down here and I’m going to look and I’m going to say. Is it I’m going to put in a switch statement I’m going to say, is it asterisk? Well, if it’s a streak, I’ve already said this resets everything so I’m going to make sure really status is off so setting realize that, as the false turns off the relay and then I’m going to erase the current time value put zeros in all the locations I’m Going to reshow the entered time I’m going to make sure the current state is 1 I’m going to set my loop count, which we’re going to talk about this a little bit but on the timer to zero in the seconds in the timer you equal to zero. So that basically resets everything back to the startup State, and if you come down here and we have, if it’s a pound sign, then we know they want to start. They want to go ahead and start doing the time or they don’t activate the timer.
So for this I’m going to take the usual use the temp values. Since I know the first two characters are the number of minutes I set temp bow equal 0 equal to the first 0 or whatever it is it’s in the number of minutes in the second one. Then I put a null in the second one and the reason I do that is. I can then call this routine right here called a tall and you can give it this. This a character array and it’ll convert it to an integer. So I take the first two digits value: the integer value and take a time 60 and that’s how many seconds so, if it’s 5 minutes you’re going to get 300 seconds right here and it’s going to be equal to 300 seconds. So now I take in. Do the same use the same temp, their value or variable and put in the second? So if it’s 10 seconds it’ll be 1 0 and then a null so it’s going to come back I’m going to say timer seconds, which is equal to 600 from the previous 1 plus 10 of 8, all make 600 10 seconds or 5 minutes and 10 seconds. So that’s that’s how I set the seconds for the timer and then I see my current state equals to this state equal to means the timer is running and we’ll get into that. We go down a little bit farther down here, so we come on down and if it’s not an asterisk or not a pound sign, then we think we assume it’s a number because it has to be.
In my case it could be a through D but I’m. Assuming using a 12 digit keypad that it’s 0 through 9 or an asterisk or a pound key, so we come down here and we say that we want to go ahead and move everything. So, as you saw when I was typing, it shifted it left and there’s. Probably the way I would do this in C does not work in Arduino and that’s, one who talked about in the past. Not all C code works in Arduino. There is ways I think you can call routines, but you want to create a library for it, but I didn’t do that because in a little bit of a hurry to get this done for tonight, so all I did to shift the numbers over was. I said that the zero position is equal to whatever’s in the one’s position. The ones position was equal to others in the twos position, the twos equal to whatever than the 3 and the 3 is equal to the new one you just put in there. So that does it basically shifts things to the left, and then I go out here and I show enter time which basically is putting whatever is in these values, with a colon between them on the screen. So, as you type, this is what this is going to do now, that dissin certain loops for every key press. Unless you go into current state 2, so let’s go down and look at the state to process, and what we do here is, if we’re equal to 2, we drop into this and if a key has been pressed.
So this is how you get out of the timer. If a key has been pressed, I then check and see is the key a star, and if it is, I am you turn the relay off class, whom you want to abort abort count up to countdown. I display the main screen again and you were out everything just like I did with the star before so it does exactly the same thing with the exception of it does turn off the relay and it enters the puts the main screen back and make sure you Go back to state one number, one where you do keypad and putting in so assuming that you’re not hitting the star key and you are in state two here’s, where it gets a little bit more complicated and how I did the timing. So you see, I have this LP CNT and it’s equal to the zero and our I mean it’s IFS equal to zero. Every time it goes past ten passes by and the reason that is, if you scroll down a little bit father, I delayed for a hundred milliseconds, so it takes ten passes by equal a second. So basically, what I’m saying here is, if it’s greater than nine. I know I’ve been by ten times, so what I want to do is I want to put it back to zero decrement the time or seconds by one show the countdown on the screen relative to the countdown on the screen, and then I come down here.
I’M. Going to say if timer seconds is equal to or less than, zero there’s the possibility, compute lessons through or somehow so less than or equal to is the safe way to do this I’m going to say, okay, I want to go back to state number one which Is where you enter in the keys? I want to turn off the relay. I want to display the code entry screen and I want to put back the enter time back to the main keypad entry and, if it’s, not that I’m going to say, I want trying to relay on because it’s greater than 0 seconds left. So the first time through here, it’s, going to UM after the first second it’s going to take and turn on the relay and it’s going to keep on through this loop and it’s only if the loop count is greater than nine. If you come down here, you see his run on increasing the loop count, so for every time ten times around here it basically does a check and decrement the timer. It should be, in theory, pretty close to a second now it’s, not exactly because it is doing other things, but I think, for the purposes of what we’re trying to use this for it’s, probably accurate enough. I didn’t actually measure that, but I probably should have before rk1 to see how accurate it was, but imagine is probably fairly accurate. It’S not as accurate is using an actual timer interrupt, but talk about that in a few in a future episode.
We need to do like a lot more on in Rupp’s and timers in that all right, so that’s this whole thing. So when this gets done, it basically goes back to state number one and we come back up to the top up here and we’re now in state one right here and we’re going through the keypad input again. So I didn’t actually watch and let you see how this finished, let me go back over here and I’m, going to go I’m just going to put in 15 seconds, so it doesn’t take real long 15 seconds and I’m going to go ahead, count start and we’ll. Let it finish so you can kind of see right now, we’re in that Orion mode or number two now we’re in current state, two and we’re going through that loop. So you remember for every second that it goes by it’s going to loop ten times and then there were two zero and we’re back to the beginning, again so that’s kind of how it falls out just like that. Okay, so let’s keep going through the code. Here a little bit, I do this on other functions on the bottom here that I want to go through so here’s, where it says the show entered time. So all I’m doing is I’m setting the cursor to the 14th position in the attitudes to the 15th position, because it’s such a zero on the 4th line and I’m writing out the first two digits, the colon and then the next two digits.
So all I do when I call this is on I’m, putting in whatever we have in these in these character. Arrays these these positions on the screen in a known and named an order, and then we come down here and here’s another routine called relay status, and you see me call that with either true or false. So if it is true, then the relay comes on which turns control, pin, which is pin 13 too high and if it’s false, then it returns the control, pin too low very simple little routine for that, okay, so here’s the show countdown and one things you’re going To see in here is I had this character array again, this one’s six in length and let’s see here one second, sorry I needed to cough still getting it for this okay. So now you see here is this temporary variable and I’m going to show you how use it in a second, but basically, what I do is I set the cursor to 0 0 I’m. Putting Asterix doll way across send the cursor to 0 1, which is the second line number row is at the end on this column is the first one it’s backward, how we normally think and members are certain to 0. So this is a really row number to first position and I’m going to put down these this letter, so it’s 20 characters and it says counting down and then I’m going to go to the third line.
First position I’m going to put in two asterisks and some spaces, and then you see here s printf, which is a standard C function. It works fine in the Arduino. So I define this six character array up here and I’m going to write out two. This actually two characters. Well, it could be two characters. It may just be one character depending on a clutz saying, force a zero here and then a colon and then out here I’m saying force a zero. So if it’s one second, for example, what’s going to put out zero one because I’m saying this is a two digit number dot d is a decimal number or a hitter and then over here I’m saying timer seconds divided by 60. So that tells me how many minutes – and that goes on this side and then over here I’m saying take time or seconds. This seems kind of funny time or seconds divided by 60 times 60 s. What this does is. It comes back with a whole number. Ten seconds divided by 60, gives you a whole number. They take it times 60 to get the number of seconds in the whole minute. You subtract that from the seconds – and that gives you the number of seconds left. It says there’s a different way of doing it, there’s a bunch ways. You could do something like this and that’s the quickest way. I can do it in my head, so anyways after I put this out.
This is a variable right here. I then print that variable out to the screen, and then I put out spaces and asterisks go to the next line and put out a whole line of attrex again so that’s. All that routine does. Is this? Show you the countdown okay and then we come down, and this is the code entry screen and you see a call clear screen. This is actually the same routine that we used in the LCD and the the keypad entry before just copy the other routine and it’s right down here, basically to spits up blanks, but then I’m putting out let’s, make it count down time and then enter time. In minutes and seconds and that’s all there is to it and to get the time at the bottom I’m using units a routine we went through, which is right here where I show entered time. So I just call that after I display that screen and that’s that’s, all there is to it it’s, not very long, it’s a ended up being 230 lines. Long and, like I said, a lot was copied from another program. I didn’t have to do a lot of rewriting on stuffs. I did some. You know new cover decoding here too, with that whole 230 lines also includes this top section of comments up here. So I did comment this out. I didn’t comment out down at the bottom, which I will do that for us to get out there in show notes and describes a little bit more, because I was kind of in a hurry in XTA.
The way I was written is when the code input was not working. The way that I wanted to do, that’s when I went to the the scroll left to right to left method, and it worked really well and it seemed like it works a little better than what the elbow was going to work as well. So because um the way the other one was doing, I was going left to right and trying to figure it out every time, but still displaying it right. The left and just doing that, didn’t work as good as I thought I was going to so. I basically chucked what I was doing and started over and did this did it this way? So one more time over here, let’s go back over here, and this is the entire project, so hopefully the people who wanted a countdown timer. This would work for Jinyan for just get rid of this row right there. You don’t need that real elastro. You only need you know this 12 characters right there, 12 numbers or territory juice that’s. All you need so anyways. That was the project for this week and I had this code out there in the show, notes and everything – probably tomorrow – probably Wednesday – at the latest privates running through edit tonight, so to be up ready to go tomorrow. But I get it all done tomorrow. So that is pretty much all when to cover this week, just a few other little housekeeping things we love having you here, live, we get a lot of emails and getting more and more, I love it.
I do apologize for getting back to people so slow. This last couple weeks, but it’s just been a little bit a little bit crazy and hopefully that gets better and actually, as you can hear, my voice is starting to turn to go because it’s the end of the day and because it works on worse play. End of the day, but as I get better too, I have a little more time to spend on things and being winter I’m, not a winter person. I really really do not like winter, and I spend a lot more time inside working on things. To keep my mind occupied I, like light so um, I have a little bit of the intersect Nisour the sad and actually use a light light sit down here and work with the light in my face for that suddenly I just help. Keep me happy, I guess, through the winter I really don’t like winter, very much, but I don’t like snow. I like cold, so it’s just the time where I could spend a lot more time in down here in this room and can do instead. I’Ll spend much time outside, like I would did in the summer time. So, as that starts to convert over ice, you know spend a lot more time working on stuff. The other thing is, you may notice I’m haven’t shaved today and there’s actually a reason for that. This is Movember, so I don’t grow facial hair, very well.
So for the next four weeks, you’ve got the barrel with a very ugly looking face, because I don’t grow facial hair very well and as a now, if you’ve ever heard on November, but it’s movement. I think it’s men’s breast cancer awareness, so a lot of my friends, just don’t don’t shave and in November and I’m going to try it this year. Although my don’t grow facial hair very well, so it’s going to look very odd I’m going to keep it a little bit trimmed. But this is actually a week I’m. Not shaving. Today is officially a week and it’s not growing in very fast, but for the next four weeks, if you think I’m unshaven or something that’s, why there is a reason I hate going on shaved. I don’t like the feeling of it but I’m doing it with some friends for this month, so you make fun of my my my lack of pitch where all you want – and I haven’t told this to Bob yet too so he sees me, can be a little Bit surprised I don’t know: okay, that is it for let’s make it this week’s a very short one, and hopefully it answered the question that I got in the email and if you have one see us, do something particular please let us know, I do have a Whole bunch of things in my list of things do I got a whole box of sensors and I just I’ve opened up and looked at them in having the time to start plugging them in.
So I have a lot of things I want to do around different kinds of sensors as well coming up, but well, if you have something you’d like to see us, do we definitely like to do that and put that kind of ahead of everything we get a Lot of emails like this week, I’ve gotten six or seven and last week that were pretty pretty deep. This was just one of the one of them. This one actually wasn’t that bad. So if you have ideas that feature shows or things you want us to cover, I also started finally playing with you do and I haven’t gotten far enough along that I’m comfortable with it. Yet I have gotten UNIX on it. I’Ve done a little bit. I want to install the the Arduino code, one that you do itself versus programming the the Arduino one that you do separately so that’s, something else I want to do. I won’t get all it done and then come into a show about it. So I’m, still working on that as well. It’S very neat box, that’s very neat, little board I’m – pretty excited about it. In fact, I’m I’ve really considered using that board, maybe for my switcher as well in the larger ones, because it has some things built into it. That would be really nice to have in the switcher versus just what’s in the Arduino and that can combine the Arduino for the button control and so like that and then use the you do for the communication part plus the touch it has touchscreen built in all Kinds of neat things are built into it, so I’m, really looking forward to spending a lot more time with that, and fortunately it’s been sitting on my desk next to everything else.
As I tear apart my studio and store trying to get all that together, it’s pretty much back together with a few exceptions of workflow items in our files. Gon na, come in tonight and be the be using the new stuff with a little bit of a hybrid. Because that’s, you have to write some code for in Windows for must picture to be able to control it and that’s, which I don’t have right. Now I try to have back tomorrow, it’s out getting the case made for it, so there’s other things that can use like. I use this thing to control the current wire cast that I have on a Mac, but it doesn’t work on the PC, so I’ve written the program on the PC. Ah, but it doesn’t work it wasn’t working right today, so I couldn’t go use it. I don’t know why it so I plunked it back to the old stuff, but as we go through all this, this is gon na start getting a little bit better instead of having all these different pieces laying around everywhere as well, so hopefully that’ll my time. For that Baloo sit up a little bit in the next week or so, and Bob will be back. Hopefully, his move is done this week and he gets back on rabid schedule and it starts getting on the call with this every week, a little bit more again. Any comments are great. I love the thought to have them if you are subscribed to us like on iTunes or something like that, if there’s a rating system there can you go get the thumbs up because that definitely those ratings help more than what people realize.
If you go out gives a give us a good rating in particularly in iTunes, it really helps us get get found a little bit quicker and that’s. What I think just helps us get the show to grow a little bit and one other thing. I’Ve. Had this question and last week I want make sure I cover this. If you buy things on our site from Amazon, we do get a little bit of a commission off that’s like 3 or so like that it’s, not a lot. Doesn’T cost you anything more. It doesn’t, you know, there’s no cost to you, but a little bit that we give back, helps us to buy the parts and things that we use in here. It helps us to pay for the bandwidth things like that right now. We very much do it. Almost all of our pockets, so if we can help offset that a little bit that’s helpful. So if you have to go to Amazon to buy something, you use our amazon link from the website, that’s that’s helpful for us. I just help to offset some of the cost that we have. Alright, everybody we’ll see you next Monday for show notes, for this show contacts and more go to the Texan TV website, where you can get show notes for all of our shows. We love to hear from our viewers and listeners. We have an email, a Twitter and a phone number where you can contact us for each show for details, visit the Texan TV website and get the show details.
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arduino 7 day timer Video
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Posted on Friday October 04, 201904 | October | 2019 Hackaday … Continue Reading »
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Posted on Monday June 17, 2019Modeling The Classic 555 Timer On A Breadboard Hackaday … Continue Reading »
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🔬 Now that you’ve gotten your feet wet, dive into the kit and enjoy all nine experiments. Order yours today: http://bit.ly/2MnQ7fr