# Getting started with Fox board D27

<abstract>
This article explains how to get started with the FOX board D27 single board computer
</abstract>

Fox Board D27 needs a bootable microSD with Linux installed to start. You can buy a
ready-to-use micorSD from [this link on our website](/pricelist?category=foxd27) or a blank microSD
and follow this article to save Linux on it.

* @article='download_foxd27'

Don't use very cheap microSD to do that. We suggest to use fast microSD for industrial use to avoid surprices during the use.

* [microSD suggested](/pricelist?category=microsd)

When ready insert the microSD inside the microsd socket:

<img src="microsd_socket.jpg" class="img-responsive" width="80%">

Check the messages generated during the boot using the serial console port. 
Any commercial USB/serial adapter at 3.3 volt can be used. On this site is available
this product: @article='USB-3V-SER'. 

Configure your terminal emulator at <code>115200,N,8,1</code>.

<img src="./console_port.jpg" class="img-responsive"  width="80%">

<br/>
Wire the board to your LAN using the Ethernep port, the FOX Board D27 will get its IP address from your DHCP server.

<img src="./ethernet.jpg" class="img-responsive"  width="80%">

Provide the power to the board using an USB-C power supply. Check that the SHUTDOWN switch is turned on <code>+5v</code> position as shown on this photo. 

Please note that this is not a power switch but is a switch used to enable the board to 
work in some low power modes.

<img src="./power_in.jpg" class="img-responsive"  width="80%">

During the bootstrap a small RGB led will blink in this way:

* Red blinks indicates activities on microSD
* Green blinks indicates the CPU load 

<img src="./status_led.jpg" class="img-responsive"  width="80%">

## Get the access from the console port:

During the boot a lot of messages are sent over the serial port by the Linux Kernel. After a while
a login message will appear:

	foxd27 login: acme
	Password: acmesystems

The command line prompt will appear waiting for your linux commands:

	acme@foxd27: 

Check for example your ip address by typing:

	acme@foxd27: sudo ifconfig
	
	eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.10.83  netmask 255.255.255.0  broadcast 192.168.10.255
        inet6 fe80::fec2:3dff:fe54:3f64  prefixlen 64  scopeid 0x20<link>
        ether fc:c2:3d:54:3f:64  txqueuelen 1000  (Ethernet)
        RX packets 2357  bytes 235274 (229.7 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 395  bytes 39181 (38.2 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 159  base 0x8000  

	lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10<host>
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 0  bytes 0 (0.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 0  bytes 0 (0.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

In this case the IP is <code>192.168.10.83</code> and the MAC address is <code>fc:c2:3d:54:3f:64</code>.
This MAC address is world-wide unique for this board thanks to the [Microchip AT24MAC402](http://www.atmel.com/Images/Atmel-8807-SEEPROM-AT24MAC402-602-Datasheet.pdf) 
mounted on the FOX D27. This chip contains also a unique 128-bit Serial Number and 2-kilobit of
serial EEPROM avalable for the user.

It is possible to know the IP address also using this command <code>ip addr</code>.

## Using the USB port

Fox Board D27 has two USB 2.0 host ports. They are called USB-A and USB-B and are located as shown below:

<img src="./usb.jpg" class="img-responsive"  width="80%">

Each port can be turned-off by changing the logical state of some GPIO lines. By default both ports are on.

USB-A power line control (line PB25)

* ON <code>sudo gpioset gpiochip0 57=1</code>
* OFF <code>sudo gpioset gpiochip0 57=0</code>

USB-B power line control (line PB24)

* ON  <code>sudo gpioset gpiochip0 56=1</code>
* OFF <code>sudo gpioset gpiochip0 56=0</code>

The port USB-A can work as host port ot client port. In this case the connector used is the USB-C power in connector.

Switch the USB-A line from the host connector to the device USBC connector (line PIOBU6)

* USB-A on host port <code>sudo gpioset gpiochip1 6=0</code>
* USB-A on device port <code>sudo gpioset gpiochip1 6=1</code>

To configure Linux to use the USB-A line as an USB client it is requested to change the Device Tree.

### Manage the 3V3_USER power line

On J1 and J2 GPIO connectors there are two pins where is available a 3.3 volt power line interruptible by software
usign the GPIO line PIOBU3. This line manages directly the ENABLE pin of PMIC that will provide the 3V3_USER powersupply.

* 3V3_USER ON  <code>sudo gpioset gpiochip1 3=1</code>
* 3V3_USER OFF <code>sudo gpioset gpiochip1 3=0</code>

It is possible to check the state of this power out line by the green led 3VU

## Manage the green leds used to display the power line states

Three green leds are used to display the state of some power lines inside the FOX Board D27

<img src="./powerlineleds.jpg" class="img-responsive"  width="80%">

* 3VO - State of the 3.3 volt out from the [Roadrunner SOM](/roadrunner)
* 3VI - State of the 3.3 volt input line to the [Roadrunner SOM](/roadrunner)
* 3VU - State of the J1.1 and J2.1 3.3 volt user power out line 
 
to limit the current absorption is it possible to turn-off this leds using this command (line PA26):

* ALL LEDS ON  <code>sudo gpioset gpiochip0 26=1</code> 
* ALL LEDS OFF <code>sudo gpioset gpiochip0 26=0</code>

## Manage the RGB status led

The RGB status led uses three GPIO lines: 

* PC9 red led
* PA25 green led
* PB13 blue led

by default this three lines is managed by the GPIO LED drived provided by Linux and activated inside the device tree
by these lines:

	leds {
			compatible = "gpio-leds";
			pinctrl-names = "default";
			pinctrl-0 = <&pinctrl_led_gpio_default>;
			status = "okay";
	
			red {
				label = "red";
				gpios = <&pioA PIN_PC9 GPIO_ACTIVE_LOW>;
				linux,default-trigger = "mmc0";
			};

			green {
				label = "green";
				gpios = <&pioA PIN_PA25 GPIO_ACTIVE_LOW>;
				linux,default-trigger = "heartbeat";
			};
	
	
			blue {
				label = "blue";
				gpios = <&pioA PIN_PB13 GPIO_ACTIVE_LOW>;
				linux,default-trigger = "none";
			};
		};


It is possible to change the default trigger (in other words the way to use these leds) changing the device three or using the filesystem three available on <code>/sys/class/leds</code>.

	ls /sys/class/leds

	blue  green  mmc0::  red

### Examples:

Turn on the blue led:

	sudo sh -c "echo '1' >> /sys/class/leds/blue/brightness"

Turn off the blue led:

	sudo sh -c "echo '0' >> /sys/class/leds/blue/brightness"

Disable the trigger for the red amd green led:

	sudo sh -c "echo 'none' >> /sys/class/leds/red/trigger"
	sudo sh -c "echo 'none' >> /sys/class/leds/green/trigger"

Turn off the green and red leds:

	sudo sh -c "echo '0' >> /sys/class/leds/green/brightness"
	sudo sh -c "echo '0' >> /sys/class/leds/red/brightness"

Read the trigger enable for the red led

	cat /sys/class/leds/red/trigger 
	
	[none] rfkill-any rfkill-none kbd-scrolllock kbd-numlock kbd-capslock kbd-kanalock kbd-shiftlock kbd-altgrlock kbd-ctrllock kbd-altlock kbd-shiftllock kbd-shiftrlock kbd-ctrlllock kbd-ctrlrlock timer heartbeat gpio cpu cpu0 mmc0

Removing the device tree association with the gpio-leds Linux driver inside the device tree might be possible to control the status led using directly these commands:

* RED ON    (PC9) <code>sudo gpioset gpiochip0 73=0</code> 
* RED OFF   (PC9) <code>sudo gpioset gpiochip0 73=1</code>
* GREEN ON  (PA25) <code>sudo gpioset gpiochip0 25=0</code> 
* GREEN OFF (PA25) <code>sudo gpioset gpiochip0 25=1</code>
* BLUE ON   (PB13) <code>sudo gpioset gpiochip0 45=0</code> 
* BLUE OFF  (PB13) <code>sudo gpioset gpiochip0 45=1</code>

<h2>Related products</h2>

<div class="row equal">
	<div class="col-md-3 col-sm-6">
		@include='card_foxd27'
	</div>

	<div class="col-md-3 col-sm-6">
		@include='card_roadrunner'
	</div>

	<div class="col-md-3 col-sm-6">
		@include='card_bertad2'
	</div>
</div>

<br/>