GC9A01 Round LCD with ESP32 & Arduino

today in the workshop we're checking out a circular lcd display module we'll see how we can use the gc9a01 display with both an arduino uno and an esp32 we'll also build an indicator dial and a pair of animated eyeballs we're going around in circles today so welcome to the workshop [Music] [Applause] well hello and welcome to the workshop and today we are going to be working with a liquid crystal display which really isn't anything new because we've worked with lcds in the workshop before what is different about this display is that it's a round display and there are a number of round liquid crystal displays that you can purchase and these things are great for instrumentation and metering applications because of the fact that they are round now the display we're working with today is from wave share you can also get it from other manufacturers and we're going to see how we can use it with both an arduino and an esp32 so before we get started of course let's go and take a look at the specifications of this wave share round liquid crystal display the gc9a01 is around 1.28 inch liquid crystal display module the name gc9801 actually refers to the embedded driver integrated circuit that is on the module and not to the display itself this is a 240 by 240 pixel ips display the device is capable of displaying 65 000 rgb colors the gc9801 uses a four wire spi bus interface the rear of the display has a connector for the spi bus and the connections are as follows vcc can be either 3.3 or 5 volts dc and this display is compatible with both 3.3 and 5 volt logic gnd is of course the ground dn is the data in on the spi bus this is often referred to as mosi clk is the clock input cs is the chip select and this is an active low line dc is the data command pin depending on the logic state the device will either be in data mode or command mode rst is the reset and bl is the backlight control that can be used to turn the backlight on or off you can also use pulse width modulation here to vary the brightness of the backlight there's another common version of this module as well that has a slightly different labeling on its pin out but can be used in almost an identical fashion however this is only a 3.3 volt device as it does not have an onboard voltage regulator in addition the data in has been labeled sda and the clock has been labeled scl but this is not an i2c device it's an spi device and it can be used in the same circuitry that we're going to be using our other device with respect to the 3.3 volt logic only when programming the device you use the same coordinates you would with a square display but just keep in mind that some areas of this display are not visible because of course it's a round device the gc9801 uses tft or thin film transistor liquid crystal display technology it also uses ips or in-plane switching screen technology ips provides a wider viewing angle than tn which is a twisted pneumatic type of display that were common in the 1980s and 90s these displays make excellent indicator panels and can be a lot of fun to use so let's go and take a look at the gc9a01 module now here's the 240 by 240 pixel round lcd module and looking at it from the front there really isn't that much to see except the face of the module itself it currently has a plastic protector on it which i'll remove so we can see it a little better now if we flip it over there's also not that much to see really you can see the driver i see you'll also see a connector over here and this is the i o connector we'll be using to connect it to a microcontroller a microcomputer and it's got four of these little posts that you could incorporate in some sort of a mounting scheme if you're building a project out of it now wave share also provides a cable that mates with this connector and you can use this for prototyping now they provide only one cable and it has a female ends on it it would have been nice of course to also have one with male ends which are a little bit more breadboard friendly but you can just plug small breadboard wires into the individual wires and use it that way and that's exactly what i'm going to be doing so now that we know a little bit more about this display and the technology behind it let's start working with it so now that we know a little bit more about our gc9801 display it's time to start working with it and the first microcontroller we're going to be using is an arduino uno now when uno of course is an older microcontroller and it is not as fast as modern microcontrollers so there are a number of things you won't be able to do with this display but for simple display functions it works just fine and there are a couple of ways that we can code for it using an arduino uno but before we do that we're going to need to hook it up so let's go and take a look at how we do that the only components we'll require for our experiment is an arduino uno and gc9a01 round lcd display we'll begin by connecting the 5 volt output of the arduino to the vcc input on the display the arduino's ground will of course be connected to the display's ground connection pin 11 on the arduino is connected to the dn pin on the display that's the data input pin 13 is connected to the display's clock line pin 10 is connected to the cs the chip select line on the display pin 7 is connected to the dc input pin 8 of the arduino is connected to the display's reset or rst pin and arduino digital output 9 is connected to the display's backlight or bl input and this completes our wiring now let's go take and look at some code we can use with our display now once you've hooked up the display you need of course some code to run on it and wave share has provided some code on the wiki that they provide for this display and the wiki is reasonably useful it's unfortunately all the documentation that they provide but it is enough to get you going and the wiki explains how the display works and then they'll give you a setup for a raspberry pi and they'll go into details about that and down here we have the setup for our arduino similar to the one we disconnected and they go through what you need to do with that and they also have an stm32 example down over here now at the very bottom over here in resources they've got the demo codes and so if you click on this you can download the demo codes as a zip file so you're going to want to do that now i've already done that and i've opened up the zip file and it opens up into the three different folders here arduino raspberry pi and stm32 we're going to go of course into the arduino folder because that's what we're using and inside here you'll see a bunch of different wave share displays we have the 1.28 inch one that's this one over here so i'm just going to copy this into my arduino folder which i have in the other pane over here and now we've got it here in the arduino folder so we can go into our arduino ide and we can open a sketchup and we'll go into lcd 1.2 h and there's a sketch over here that we can open now when we open up the sketch you're going to get a number of error messages at the bottom about unrecognized characters and it has to do with two of the many files that are included in this sketch over here and they tell you that there is a way that you can repair this that you can run a utility etc to do this but uh it actually won't work the utility they have you run is down over here in tools and it says fix encoding and reload the problem does seem to be and we'll take a look at one of them over here it's the led drive lcd driver cpp has one of these problems if you scroll down over here i think i can see what the actual thing they're complaining about it's over here this little question mark there are a couple of places where they've used comments and they have a chinese character set and at least one of the characters isn't recognizable and it gives this question mark now the only problem appears to be within comments so if you actually try to compile the sketch the sketch should compile just fine we'll go and try that right now and it does compile correctly so let's go and take a look at the sketch now as you can see there are several files included with it but this is the main file over here and it starts off by including a number of libraries including the spi library it also includes an image and the image file is an image that has already been converted for use with an lcd and we'll talk about that in a little while in the setup it basically does everything in the setup it configures the lcd it paints the new image to the lcd and it goes and does a number of things draw circles draws lines it draws the image it draws strings in both chinese and english and draws a number of lines now there is no real documentation for this however you can go in and find a number of things in uh in this other folders that come with this excuse me now over here is another folder where we do the actual configuration so you'll see the configuration of the gpio pins over here and there is another folder over here gui underscore paint and gui underscore paint cpp this is where you'll actually find all the different functions and so you'll go to a function for example this set pixel and it tells you the parameters of it that you need over here so this is basically your documentation here also in gui paint down over here you'll notice that down over here they've defined all the different colors that you can use just by using text rather than passing rgb values so that's good to know and using that you can go through and make some changes on this code if you want to you can use different colors you could use a different rotation over here etc and again you can just go back to those other two files as kind of a reference so let's load this up to our arduino and take a look at our display so here's a test of our wave share display and as you can see it draws this image fairly quickly and you can see it's got a number of different circles it's got a circle around it over here it's made to look a bit like a watch and so it's got some marks over here at four different coordinates and what look like the watch hand and our text in both english and in chinese here plus a graphics over here which is the wave share logo now it's it's all very simple and it's a very quick display but it does show you how we can use this wave share display now as i said you can go into this and modify a few things to see how it works for example paint new image over here has four different parameters in it and it's the image width the height the background color and this number over here is the orientation in degrees so let's change that to 90 degrees and also we're going to draw a circle over here and as we can see it's a blue circle why don't we change that to yellow okay and now we'll load that back up to our arduino and the upload is complete and it'll redraw and now you see we have a yellow line and we've changed the orientation now we've moved it over 90 degrees and so by making simple changes in that code we can affect the display and we can see how we can use that code to write our own displays however the wave share library is not the only library that we can use with this display so let's go and take a look at another one now the example code provided by wave share is quite useful however there are other libraries that we can use with this display as well and one useful one is this one that you'll find up on github the adafruit gc98 library now this is an adaptation of the adafruit gfx library specifically made for the gc9a01a so it will work with our display and it will provide us all of the power of the gfx library and the gfx library is extensively documented and so you'll have a lot easier a time writing code for this library than you might for the wave share one now to install this we'll need to do it from github and grab a zip file so let's go over here and download a zip i'm going to put that in my downloads directory and it's been downloaded so we'll go into our arduino ide and go into sketch and go into include library and add zip library and we'll navigate to downloads and there it is over here and we will install this and now it's been included in our libraries now let's go and take a look for some example code so we'll go into examples and we'll find right over here adafruit gc9a01a and there's one example called graphics test and we're going to run that one now again this is an adafruit example from the gfx library and it's just been adapted to this now we're going to need to make one change in this sketch and it has to do with the way that we've wired everything up they have dc set over here to pin nine we've wired ours to pin seven so we're going to change that to a seven and that's the only thing we need to do now we can take a look at the sketch it includes the spi library which of course we need to communicate with the device it includes the adafruit gfx library so you'll have to have that installed and if you've been doing any work with displays you probably have that installed because it's a master library that is used for many different things if not you will need to go and install adafruit gfx and you can do that within the library manager and then of course we include our new library as well we define the pins we're using for the spi note that we only define a couple of them because in the arduino uno some of these pins such as the data and clock pin have already been defined for us and we create an object over here called tft bypassing those parameters to it in serial in the setup we're going to start our serial monitor just so we can take a look at the progress of our tests and we're going to go and run a bunch of these tests and so we're going to run a bunch of screen fill tests some line tests etc every one of these tests are going to be run from within the setup so we're going to run a series of different tests and then we're going to go into the loop and we're going to set our text rotation differently and we're going to run a test text and then we're going to rotate it a little bit more and run it again so it'll keep printing the text forever now the um the test that we're going to run over here test fill screen goes and does a bunch of fill screens and it gives you a bunch of different colors then we're going to do a test text and the test text is going to say hello world and then over here it's going to give us some interesting text that we're going to print on the screen now this may look like a bunch of gobbly but actually if you're a science fiction fan this text may seem familiar because this is from a science fiction series actually a science fiction comedy series for many many years ago and i want to see if you can guess what it is and i'll let you know at the end of the video what the actual answer is for this gobbly so there's a number of different tests to test lines etc where they draw a number of lines on the screen test fast lines and these are all called from within the setup routine so let's load that up to our arduino and take a look at the results and so here's our display demonstration right now and it's running through a number of different patterns and these are all the things that you saw in the setup routine over here and it's going to go through a bunch of these patterns and then eventually it'll land on the text routine that is going to be in the loop and it'll just keep changing the orientation of that text and we'll continue to print it and there we go we're into the text routine right now and the text of course is that mysterious text that i was talking to about when i outlined the code for you and again if you're a science fiction fan you may indeed know what this mysterious text is but at any rate as you can see it can definitely write to this display and because we now have the power of the adafruit gfx library behind us we've got extensive documentation and we can do a lot of work with our circular lcd display using it so we've seen our gc9801 circular display in use with an arduino and we can see that it works well and has very vibrant colors but as i mentioned the arduino is not the fastest microcontroller especially when compared to newer more modern microcontrollers so now it's time to use a more modern controller and the one i'm going to be using is the esp32 so let's go and take a look at how we hook this up and then we'll look at some code we can use for our display with an esp32 for our experiments we'll require an esp32 module the dc 9a01 round lcd display and a potentiometer i used a 10k linear taper pot but any value of 5k or above will work we'll begin by connecting the esp-32's 3.3 volt output to the vcc input on our display the esp-32 ground is connected to the display's ground gpio pin 23 is connected to d in gpio 18 is connected to the clock or clk input gpio 22 is used for the tip select of the display gpio16 is the dc connection gpio4 is the reset or rst connection and we'll be connecting the backlight input to the esp-32's 3.3 volt output we'll connect one side of our potentiometer to an esp-32 ground the wiper of our pot will be connected to gpio pin 14 and the other end of our potentiometer will be connected to the esp32 3.3 volt output and this completes our wiring now in order to use the display with the esp32 we're going to install a library and we're going to use the tft underscore espi library which we can get through our library manager so go and open your library manager and then filter your search by tft underscore espi and you'll see it down over here let's go and install that and our library has been installed however before we can use our library we're actually going to need to modify a few things in it now let's go into our arduino folder which i have over here and we'll go into our libraries folder which is down here and we'll scroll down until we see that library tft underscore espi there it is and there is a user setup dot h over here let's open that with a text editor i'm going to open it up with genie and these are the user defined settings for the library and we're going to need to change these to match our display now there's two areas we're going to have to do this in over here you have the display driver type and you can only have one driver enabled now we're not using this one so we're going to comment it out right now and we're going to scroll down and we'll see the gc9801 driver we will uncomment that by removing the two slashes okay that's the first step that we need to do now we're going to scroll down over here it's around line 215 i believe and this is where we define the pin outs now what we're going to have to do is enable and change some of these so i'm going to enable all of these first uncomment them i mean not enable them i'm not going to do that to the backlight because we haven't got that connected now we need to change some values over here so this first one is going to be 23 for the mosi our clock is going to be on 18 our tip select is going to be on 22 our data command or dc is going to be on 16 and the rst is going to be on 4 and once you've done all that you can go and save this and you've now modified the library correctly for use so now that we've installed and configured our library it would be a good idea just to check it out with a quick sketch to make certain everything's working we can do that by going to file example scrolling down to examples from external libraries and looking down until we find tft underscore espi and you'll notice there are a number of demonstration programs that came with this library we're going to go into test and diagnostics and open the first one called color test and as its name implied it just basically prints a number of different colored bits of text out to your display just to make certain that everything is working and it's a fairly simple sketch and it can actually be used to understand how we use this library we start by installing the spi library and of course our library the tft underscore espi library and we create an object called tft with it and we go through the setup and you can see how tft works you initialize it you can fill the screen with a color you can set your cursor position set the text color and also the text background over here and then we can use a number of print lens in order to print text out to the display and println is going to work the same as it does on a serial print so it prints and then adds a line feed to it so it's quite easy to go and print out the display we can continue to change the text color and print more things etc etc now if we go into loop you'll notice that it's basically a lot of the same we first of all start off by not inverting the display filling the display setting the cursor and then going through and printing out a number of pieces of text in different colors delaying for five seconds and then we invert the display and basically do the entire thing all over again so it really is a pretty simple sketch but again it's just being used to test to make certain that our display is functional so let's load that up to the esp32 and check it out so here's our display color test and this test is basically just to make certain that we've got everything wired up right and configured correctly and we do because we're displaying things on the display now it just simply displays a couple of lines of text in different colors and then it inverts the background color to white and then changes it to black etc etc so there's not really much to look at over here you'll also notice that all of the text is shoved off to the side and the reason for that of course is that this program was never written specifically for a circular display it's just written for any lcd display and so you could go back into the program you'll notice there were coordinates in the program when it printed the text you could adjust those coordinates to move the text more into the center of the screen but i'm really again using this test just to make certain that i've got the liquid crystal display wired up correctly and that i've got the library configured correctly and it seems that i have so now we can move on to something a little bit more interesting now to run something a bit more interesting again we can look at some of the examples in the tft underscore espi display and if we go into the sprite sub menu over here and pick the first one animated dial we'll find a program that seems like it was written specifically for our display it actually wasn't but it is just written for a circular display as 240 by 240 so that's a pretty handy thing to have now the animated dial sketch does require another library that you're going to need to install and that's this tjpeg decoder library so just go into your library manager and install that library for this to function now this is a relatively long sketch but it can be broken down into a couple of simple functions really well they're not simple functions but basic functions plot needle is the main function and what it's going to do is it's going to create a gauge and you can move the needle on the gauge and so you can plot the needle by specifying a number over here and the angle that you want to plot that now over here we've got the two functions create needle and plot needle and you can take a look at how they work you'll find a lot of mathematics involved in anything that involves a circular display simply because we're trying to plot coordinates onto a circle and so it's a little bit more than just picking x and y coordinates now you'll also notice that this sketch has two other files in it the first one is a font file and it contains a bunch of hexadecimal data which is the font we're going to use and then dial dot h is actually a jpeg picture that is again being converted into a binary file into a hexadecimal file and you can do that conversion yourself if you want to change the image they have a url that you can go to over here and i've got that open up over here and it's a file to hexadecimal converter so you can basically take something like a jpeg file that you've already sized to the correct size that's very important and just enter that file into here and the output will appear there and then you can just copy that to your clipboard and paste it into a file and they did this with both the jpeg and with the font they also put a font file into here and got it output and there's a few other utilities like this up on the web there's another one that i've used before from a place called rinky dink electronics that does basically the same thing and so it will produce data like this that we can use in sketches that need to drive lcd and other displays if you look inside the loop over here we've got really everything that's happening where's the loop it's up over here it's a little bit hard to find there it is here's the loop and basically we're generating a random number over here from 0 to 240 and then we're going to use plot needle to plot that to the display and we're going to delay that by two and a half seconds and then do it over again so what we're going to do is we're going to get a display which shows a value and then two and a half seconds later we'll pick another random value and it'll show you how you can use these round lcds as an indicator so let's go and load that up to our esp32 and check it out so here's a demonstration of our animated dial and as you can see it's moving back and forth of course the random number generator is generating a number between 0 and 240 and every two and a half seconds it just moves over to it i'm going to reset it because i want to show you something about it that's a little bit different if i reset this right now it starts you'll notice it has these little numbers around the screen but they disappear as soon as the needle goes over them i don't know if that was intentional or if it's a programming error but it's a rather unique little effect at any rate though it's a very attractive little display and certainly would look well as a panel gauge or something it would be very nice if we could modify this for our own purposes and of course we can do that and so let's go take a look at what it would take to modify this animated dial and use it for our own purposes now we can use our animated dial example sketch in order to produce a gauge that we can actually manipulate rather than using random numbers and there's not too many modifications you'd have to make to it what we're going to do in this case is take the potentiometer that we have and use its input use the position on the pot to determine the position on the gauge and so it's a pretty simple little application really the first thing we're going to need to do of course is define the pin we've connected the plot tooth let's do that okay so i've defined my pot pin as gpio 14 which is where i've got my potentiometer wiper connected to and we can go down over here and customize it a little bit more over here it says degrees because that's what our display was reading before we can make this anything that we like really so i'm going to call it input level of course temperature humidity pressure whatever you're measuring you could put into here and now we'll go down into the loop and in the loop we've got this random number generator that's creating data we want to replace that with our pot data let's just remark that out so that we still have it there as a reference and we don't want the r in that thank you we'll just take this sorry having a bit of mousing problem over here okay and what we want to do is get the data from the plot so it's going to be a map and an analog read so we'll do an analog read of the plot pin and it's going to go from 0 to 40 95 because that is what range we're going to get with the 12 bit a to d and the esp32 and we want to put that to a range of 0 to 240 and again you could go through the sketch and adjust those numbers so you don't need to use 240 but i'm just going to use that for demonstration purposes okay so we've modified this now if we want to it's a good idea to go and save this so we'll do a save as and we'll save this as animated dial part mod and so now it's a modified one for the pot you wouldn't have been able to save the original one because there's some read-only files plus this prevents corrupting the original sketch so let's load that up and see if it works so here's our modified meter with the potentiometer controlling it now instead of just being controlled through a timing circuit and it seems to work pretty well if i go all the way down to zero i've got zero over here i can move it up to the top now you'll notice that there is a little bit of a delay or hysteresis inside this and this is intentional in the design if you look at the code you will see that they're intentionally moving these at a specific place between the different readings and it's actually kind of a nice feature if you don't need something that is changing rapidly then i think this is actually a very nice feature sort of a dampening effect and everything but it does seem to work pretty well and of course you could adapt this to basically measure just about anything and you certainly don't need to just use the range of zero to 240 you can pick pretty well any range that you want to for this kind of a design so this is a way that you could use one of these round lcds as a very effective panel meter now the final thing that we're going to do with the display today is actually the reason i bought the display in the first place and i'm a little embarrassed to admit that but please don't judge me on it they actually aren't the right displays for this project but they're pretty close and the project is the animated eyes now you may have seen this before a couple of animated eyeballs that print out on displays they can be lcds or oleds and it's really a pretty cool thing to see now you can run the animated eyes on the esp32 as well there's a version of the sketch and i'll show you that we certainly won't go over the entire sketch it's absolutely huge but i'll show you how you can configure it for those displays but before i do of course we need to hook a second display up to our esp32 so let's go and take a look at how we do that to create our animated eyes display we'll start with the same display wiring that we had for the esp32 we'll add a second display and we'll add the second display by connecting every wire in parallel with the original display with the exception of the cs or tip select line as this is the one that distinguishes the individual displays we'll keep the cs line on our original display on gpio pin 22 as it always was the tip select for the second display will be connected to gpio pin 21. there are also some additional components you can add now these are optional and you don't need to use them but they can make the display more interesting we'll need an analog joystick and two momentary contact normally open push button switches we'll begin the wiring of the joystick by connecting its ground to an esp32 ground we'll connect the vcc pin on the joystick to the esp32 3.3 volt output the vrx which is the x-axis potentiometer will be connected to gpio pin 33 vry which is the y-axis pot will be connected to gpio pin 32 and sw which is the internal push button switch in the joystick will be connected to pin gpio27 we'll connect one side of both of our push button switches to the ground the other side of one push button switch will be connected to gpio pin 26 this will be our left wink button and finally the other connection on the second push button switch will be connected to gpio pin 14 and this will become the right wink button and this completes the wiring now let's take a look at the code we need to use to run our animated eye display now the sketch for our animated eyes is included as one of the example sketches with the library we loaded so we can go into file go down to examples and scroll down to examples from the other libraries until you get the tft underscore espi now inside here go into generic and you will find an animated eyes one and animated eyes too the one sketch is just for one eyeball we're using the one for two eyeballs now a lot of the files in this sketch are read only and so in order to make some modifications and you will need to make some modifications you're going to need to make a copy of the sketch so just go into your file menu here and then do a save as and save it as another name and i've already done that so mine is called animated eyes underscore 2-mod now the sketch has a number of files in it and i'm not going to go over it by any means it is a huge sketch there is actually a complete article on adafruit's website that explains the operation of the sketch and i have linked to that in the article accompanying this video in case you're really interested but there are some files that we need to be aware of and some that we need to mod now this is the main file over here we don't actually touch this file at all this config.h is where all of our configuration settings are going to be set and we're going to go through that in a moment and set a couple of config settings i functions are just as it says a number of different functions for the eyeballs and again we aren't going to touch that now user cpp is an interesting file this file will be called one of these cpp files user cpp user backed user x mass can be called if it's enabled over here and you change this to a 1 to enable it or a zero to disable it so right now this one is enabled and these other user codes over here are set to zero so they are disabled so you can only have one of these enabled at a time and what this is is additional code that you can add to the sketch and it provides a very easy way of doing it now over here is the setup function for example so any code that you add in here will be run during the setup function and down over here we also have a similar function for the loop called user loop and any code you put in there will run in the sketches loop now by default there are only comments and no code over here but if you wanted to modify this project this is how you would do it these other two are ones that are already set up so this is for an animated bat that uses a servo motor and this is for a christmas display that uses some neopixel lights in addition to the eyeballs this one over here just gives a little text file that shows you how we're going to wire everything up we've already got it wired so we don't need to use that so let's go back into our config file because there are some things we're going to need to configure now over here you can configure what style of eyeball you want and there's a number of different ones you can only have one of these includes and by default the default i which is sort of a human eye is included we're just going to leave that alone the display hardware settings over here we don't need to change anything in the hardware settings because we've already wired everything up this way however this will switch the position of the eye and i found with our display setting this to 50 and setting the other eyeball to 50 will sort of center it into the display rather than putting it up at the edge and again you can start playing with those in order to get the correct position now down over here we've got some pins we need to define we have a blink pin and this is the pin that the switch is going to be connected to in order to blink the eyes and in our case the switch is the one inside the joystick and so that is going to be connected to 27 to gpio pin 27 now we have a wink pin for the left wink and that is going to be connected to gpio26 that's one of our two push buttons and the other one which is the right wink is connected to dpio14 so you want to edit those and then we're going to go down a bit further and edit the connections for our potentiometer so our potentiometer over here will replace the a0 with a 33 because we're on gpio33 and we'll replace a1 with a 34. oops not 134 just a 34 will do us and that's it and now we can now do a control s to do a save and that's all we need to save over here we can load the sketch up and take a look at our animated eyes in action and here's a demonstration of our animated eyes in action and you can see our two eyeballs staring back at us right now now on their own they'll occasionally blink but you can make them blink yourself you can blink both eyes simultaneously by pressing down on the joystick and that'll turn them off and releasing turns them on you can also do the individual eyes i've got this one for the left eye and this one for the right eye and by the way when i'm talking left eye and right eye i'm speaking of the perspective of looking at the eyes obviously if these were our own eyes that would be reversed you can also use the joystick to move the eyes around and get them to look at different things and that's pretty cool moving over there and it's a pretty neat little project actually now it was originally intended for displays it didn't have as high resolution as this it was made for 128 by 128 displays so as a result the eyeballs don't fill up the entire display and that's unfortunate and i haven't been able to find any configuration settings that can change that i think it's actually more than just a configuration setting i think you actually need to recompile the files that hold the eyeball images so it's a bit involved in order to make it bigger but still it looks pretty good with this display over here and i think it's a pretty cool demonstration and it's something that you can easily hook up the most difficult thing of hooking it up is hooking the two displays up since they're mostly in parallel what i did is i took the wiring for the displays and moved it to this part of my solderless breadboard and then after that i just wired the two displays together and if you do it step by step it'll turn out just fine if if not you can troubleshoot by just driving one display at a time until you get the wiring right but otherwise it's a pretty cool little project and it's a project that'll keep looking back at you well that wraps up our look at our circular display i hope that you enjoyed it and i hope it's inspired you to think of a few applications for a circular display in some of your own projects now i want to address the little riddle i gave you back when we were working with the arduino within the demonstration sketch there was some text and i mentioned that if you were a science fiction fan or a science fiction comedy fan you might know what that text was well that text was from the hitchhiker's guide to the galaxy which was an excellent set of books by douglas adams it was an excellent bbc radio play it was an excellent bbc television series and a really terrible hollywood movie and the text in question is actually vogue on poetry now if you're a fan of the hitchhikers you will know that vogon poetry is the third worst poetry in the galaxy and vogons also use it as a form of torture and if you had to read a lot of that stuff i can think that you would see the torture aspect so there you go other than electronics we're also getting some culture here in the dronebot workshop now if you want to experience more of that culture you can just subscribe to the channel and it's very easy to do of course all you need to do is hit the red subscribe button and then click on the bell notification and assuming that you've enabled notifications you'll get notified every time i make a new video now if you want to get the code i use today or get more information about these displays there's an article on the dronebotworkshop.com website you'll find the link to that below the video while you're on the website please consider signing up for my newsletter it's not a sales letter just my way of occasionally getting in touch with you to let you know what's going on here in the workshop and of course if you want to discuss these displays the place to go is a dronebot workshop forums where you'll find a bunch of people who are just like you totally into electronics and maybe even a few who are into the hitchhiker's guide to the galaxy so until we meet next time please take good care of yourself please stay safe out there and i'll see you again very soon here in the dronebot workshop goodbye for now [Music] you

Channel: DroneBot Workshop

Views: 162,423

Keywords: arduino, esp32, gc9a01 round display, gc9a01, gc9a01 arduino, round lcd display

Id: k2c2zCmC_X0

Length: 45min 46sec (2746 seconds)

Published: Sun Jun 05 2022