#16x2 alphanumeric LCD and four push-button on Arietta G25

<div class="lead text-success">
Daisy-24 is a mini I2C terminal which mounts a  <b>Winstar</b>
alphanumeric 16x2 chars LCD module and 4 push buttons. This article illustrates how to use it with Arietta G25
</div>

<img class="float" src="./daisy24_wirings.jpg">

This is the wires between [Arietta G25](/arietta) and the [Daisy-24 module](/DAISY-24):

| Signal | Description                        | Arietta Pin # | Daisy 24 pin |
|--------|------------------------------------|---------------|--------------|
|  3V3   | Power out 3.3 volt DC              | J4.5          | 3V3          |
|  SDA0  | Data  line bus 0                   | J4.14         | SDA          |
|  SCL0  | Clock line bus 0                   | J4.12         | SCL          |
|  GND   | Ground                             | J4.9          | GND          |


##Code examples

<ul class="nav nav-tabs">
	<li class="nav active"><a href="#python" data-toggle="tab">Python</a></li>
	<li class="nav"><a href="#c" data-toggle="tab">C</a></li>
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	<div class="tab-pane fade in active" id="python">
	
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			<br/>
			<p class="text-warning">
				<span class="glyphicon glyphicon-info-sign" aria-hidden="true"></span> Install <a href="/ablib">ablib.py</a> to try these examples.
			</p>
		
			<div class="panel panel-default">
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						<a data-toggle="collapse" data-parent="#accordion" href="#collapseOne">Hello World !</a>
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				<div id="collapseOne" class="panel-collapse collapse">
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						@pg='python/daisy24/hello.py' 
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				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapseTwo">Cursor control</a>
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				<div id="collapseTwo" class="panel-collapse collapse">
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						@pg='python/daisy24/cursor.py' 
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				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapseThree">Text contrast control</a>
					</h4>
				</div>
				<div id="collapseThree" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='python/daisy24/contrast.py' 
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				</div>
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				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapseFour">Font size</a>
					</h4>
				</div>
				<div id="collapseFour" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='python/daisy24/font.py' 
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				</div>
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			<div class="panel panel-default">
				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapseFive">Push-button and backlight</a>
					</h4>
				</div>
				<div id="collapseFive" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='python/daisy24/readkey.py' 
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	<div class="tab-pane fade" id="c">
	
		<div id="accordion" class="panel-group">
		
			<div class="panel panel-default">
				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapse1">Hello World !</a>
					</h4>
				</div>
				<div id="collapse1" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='c/daisy24/hello.c'
					</div>
				</div>
			</div>

			<div class="panel panel-default">
				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapse2">Backlight control</a>
					</h4>
				</div>
				<div id="collapse2" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='c/daisy24/backlight.c' 
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			<div class="panel panel-default">
				<div class="panel-heading">
					<h4 class="panel-title">
						<a data-toggle="collapse" data-parent="#accordion" href="#collapse3">Push-buttons</a>
					</h4>
				</div>
				<div id="collapse3" class="panel-collapse collapse">
					<div class="panel-body">
						@pg='c/daisy24/key.c' 
					</div>
				</div>
			</div>

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##What to do if not works

Check if exists a device called __i2c-0__ by typing:

<blockquote markdown="1">
<pre class="minicom">
root@arietta:~# <b>ls -al /dev/i2c-0</b>
crw-rw---T 1 root i2c 89, 0 Jan  1 01:48 /dev/i2c-0
</pre>

if it not exist go on the [Device Tree Compiler page](http://dts.acmesystems.it/arietta/)
and create a new device tree file with i2c-0 enabled follow the instructions
to copy the new device tree file on yoru microSD and reboot.
</blockquote>

##Related links

* @article='ablib'
* @article='user_i2c'
* [Schematic in pdf format](http://terzo.acmesystems.it/download/schematics/schematic_daisy24.pdf)
* [Winstar display model WO1602I-TFH-AT# datasheet](http://www.acmesystems.it/download/datasheets/LCD-1.pdf)
* [Philips PCF8574 datasheet](http://terzo.acmesystems.it/download/datasheets/PCF8574.pdf)

##Buy

@shop='DAISY-24'
@shop='ARIETTA-G25'