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But in this lecture, I show you how to use the permit 280 with your E.S.P, 32 using micro python.

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Now, unlike in the previous lecture, we are to learn how to use the DHT 22 using a driver that comes

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with the micro python firmware.

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The two hundred and eighty does not have an integrated driver, which means that you need to go out

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to find one that works with your set up and then imported into your S.P.C.A. stored in the flash memory

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so that your script can use it.

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So this is the main difference between the approach that we used in the previous lecture with the 22

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and the one that we use now with the BMY 280 is that we're going to use a third party micro python driver

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for this sensor.

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In most cases, this is the approach that you have to take with pretty much any other peripheral to

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your ESP 32.

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You'll have to use Google or some other search engine to look for an available driver for the device

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that you want to use.

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In my case, I find that awesome micro python dot com contains an excellent list of drivers or libraries

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for Macra Python.

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Not all of them work in my experience.

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But you've got a good chance that whatever hardware you want to use, you will find a micro python driver

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in this list, in particular for the BMY 280, he could look for sensors and say around.

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Here you'll find that the BMY 280 has a few options, so there's 280 this 180 as a 280 with the 266.

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There's another one here.

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So there's a bunch of potentially working drivers here.

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There's no sure way to know which one is actually going to work, because some of these, for example,

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may have been written in the past for previous versions of the marker Python firmware.

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They may not be working perfectly for your current setup.

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So it's a matter of just trying out some of those and figure out which one eventually works.

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In my case, I found that this one works perfectly with my setup, with my SB 32, and I believe that

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it is this one here, perhaps.

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That chick.

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Now that.

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Not this one either.

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It's by Robert 8H.

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Like this one here.

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So the name here does not really indicate the author or the source, but as a matter of trial and error,

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eventually you will find the one that works for you.

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So once you have access to the source code of the driver that you want to use, the process includes

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taking a copy of the driver.

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So in my case, I have determined that a lot of trial and error that being made to 80 underscore float

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dot p..

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Why is the driver that works?

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You want to go and copy the raw version of this driver?

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Just copy the whole text.

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Then you can go and create a new file.

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Anthony Paiste.

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The code in.

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Then go ahead and save it on the device.

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In my case, I've already got the source code saved under this file name here, so I won't do it again.

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But you type in the phone in the file name is important because you will use this file name to import

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the library into your script.

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He'd cancel here and get rid of that a new tab and you'll see that this driver is stored on my Microplace

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device.

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My guess 32 under this file name, he can take a little bit of time to have a look around, become familiar

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with the features of this source code.

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An interesting variable here is the address and the default address of the sensor.

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It is 76 in most cases that is going to work.

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It is going to work with my sensor because I haven't shorted any of the pads here in order to change

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the default address.

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So I'm going to go with the one that is configured here.

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I can see the operating modes.

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So how many samples do you want to take in order to improve the accuracy of the readings further down?

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Using the name of the class will be using that later in our input statement, you know, script, you

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can see the constructor here as well.

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So the parameters for the constructor and so on.

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So there's also a few functions that you may want to use a bit later.

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There's a few ways by which you can extract the environmental data from the sensor and you can learn

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all that, not through the documentation, even if it does exist in this case.

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Go back to the root of this repository.

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You'll see that there is a little bit of documentation and it's telling you how to use the driver.

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But if it doesn't, you can always go and have a look at the source code.

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Python is very often self explanatory, so you can do that.

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So become familiar with the driver.

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And then go ahead and construct your own sketch.

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I have some information here about my setup, which you can copy.

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The most important thing to remember here is a type of R-squared, see that we are using.

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So I'm actually going to remove this because it's not totally true.

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And I'm going to explain what I mean by that.

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Notice that the E.S.P 32 has a hardware R-squared interface, and this is something that, of course,

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you can use with your sensor or with any other squishy device that you want.

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But the micro python firmware has an ice quixey implementation that allows you to also use software

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ICE see.

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So let's have a look at it.

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And I've got a link to this page here in my header right here.

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Right, so go and have a look at this, the ice could see implementation in micropayment for the SB

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32 allows you to use either a hardware ice creates the interface or a software ice Quixey interface

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in our example and be using soft ice quazi, which allows me to nominate any to SEAL and Steet.

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And those will work perfectly well with my current high squidgy device to be in the sensor in later

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lectures, in particular in the lectures on display at an OLED display.

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So I'll be using the hardware interface just to get a little bit better and more consistent performance

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that students will be using a higher speed device.

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The display.

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But here I want to show you how you can go about using soft ice Quixey instead.

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I squit see in my script I've used the Jupiter for for the FDA.

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They've a pin and then you're twenty two for the clock and.

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It just looks like this this is how you can create the ice Quixey object by calling the soft I swear

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to see constructor, they pass the two tipoffs for clock in data and the frequency doesn't really matter.

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You can go for a variety of frequencies and it will still work.

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So here I'm going for four hundred kilohertz.

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OK, the next thing that I'm doing here in line 35 is to import the driver to remember that the name

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for the driver is being made two hundred and eighty underscore float, which is you can see right here,

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you import this module by using the file name, excluding the dot p y extension.

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So that's how you imported that, because this is quite an extensive name to be using it in our code.

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I rename it by using the S keyword as PMA two hundred and eighty.

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So from that point on, which I'll be able to use the code inside the driver by using the BMY 280 dot

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notation instead of this whole thing.

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Right.

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So if I had just said import this.

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Without doing the renaming here, I would have to use this notation to make reference to code inside

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the driver code.

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All right.

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Let's go back to the original and another thing to notice here is that because this line is quite long,

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if I make if I really arrange the parameters one next to each other.

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You said that it takes a lot of space horizontally in Python.

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You can split lines like this so that you've got one parameter per line just makes everything fit a

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little bit better.

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So I'm using the square see object that I created in line 37.

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And then I'm also setting the mood in the address, again, using the constants that I have found in

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the drive itself.

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So here are the operating modes.

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Constants are usually eight bit here or the eight sample shown in the sample option.

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And then for the address I am using the default.

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The trees are clear.

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If your eyes could see device is quite a different address, then of course you can adjust that to the

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appropriate correct address.

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These two parameters just point to defaults anywhere.

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So instead of this whole thing could have just said this and it would work just by passing the ice Quixey

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object and leaving the rest of the parameters to the default values.

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OK, that's about it with the set up, the rest of the code should be fairly familiar instead of using

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an infinite loop.

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I'm going to use a timer here and I'm taking one reading every 1000 milliseconds, every one second.

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And when the clock ticks, the hardware timer will call the sensor ESR function right here.

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There's a couple of ways by which you can grab data from the sensor.

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First is to call the values property on the object, on the B in the object, and that is going to print

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out all three values.

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Or you can be a bit more selective and you can pick one value at a time.

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So here's the temperature, here's the humidity, and here is the story.

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Here's a pressure and then here's the humidity.

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Now, one thing that I want to mention here is that this parameter of this variable, I should say,

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returns a python tuple so of good information about what that is.

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In case you're not familiar with tuples, but think of a table.

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There's an array, but in a regular array, each cell must contain data of the same data type.

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So you either have, for example, an array of integers or an array of strings, et cetera.

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A top off, on the other hand, can contain data of different types.

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So each cell in a couple can be a number, can be a string, can be another array.

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Even so, you can use the same notation as if this was an array.

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But the difference is that, as I said, it contains items of different types and unlike an array as

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well.

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Another difference is that a table is immutable.

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So once you set it, you can change its values.

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So if you're curious, just go to this location and read more about tabs.

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So this about it.

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Let's go ahead and try this program out.

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I've just saved it and I'm going to run it on the device and that's what comes out.

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Right, so you can see that.

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The.

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Print statement in line 45 returns this line.

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Can we stop the execution?

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I'm going to click on the stop button here, because this is not an infinite loop.

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It's a timer.

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So hitting control.

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See, it's just touch and go.

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If I hit control on the exact moment when this function is executing, then the program will stop.

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Otherwise it will not catch it at a moment where the problem is actually running.

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Anyway, so line forty five prints out this table, so that's what a table looks like, parentheses,

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and then he's got the items.

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This is item zero item on and item two.

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And if I want to print out the individual components of the tuple, the individual cells of the couple

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and the values, then I go with this array notation.

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So this should be a meat value zero.

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And it looks like this.

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It includes the C symbol as well.

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He's a pressure for being sworn in the humidity with the percentage sign for used to.

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OK, now, if you're curious as well, have a look at the driver, could you expand this window a little,

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you know?

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So I am calling.

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The values function search for values in here.

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So the values function is in line two hundred and forty, and that's what comes back to the caller.

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So you can modify this, of course, if you don't want the symbols to appear.

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You can just remove them in the source code of the driver, but you can modify the couple that is returned

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by just making the appropriate change in 1955.