View source for Wifi and Bluetooth on the DEV-IOT6U

{{#seo:
|title=Wifi and Bluetooth on the DEV-IOT6U
|titlemode=append
|keywords=wifi, bluetooth, bt, dev-iot6u, imx6u, example
|description=Examples of using Wifi and Bluetooth on the DEV-IOT6U
}}

== Wifi ==
The packages required to connect using the wireless interface should be pre-installed on the DEV-IOT6U. ([[Wifi|Steps to install needed packages]])<br/>
<cl>1. Changes to some configuration files will be necessary, so remount the root filesystem with read and write permissions.
{{cli | indent=2 |  mount -o remount,rw / | hostname=somimx6ul}} 

* Wireless networks can be found using the scan option of <code>iw</code>.
{{cli | indent=2 | iw dev wlan0 scan | hostname=somimx6ul}} 
: A detailed list of the nearby networks will be printed out to the terminal. To identify the SSIDs and respective signal strengths of the network(s) more easily, pipe the output of the <code>iw scan</code> command through <code>grep</code> to scan for the keywords "SSID" or "signal". The closer the value of the signal strength is to 0, the stronger the connection.
{{clo | indent=2}}
{{clio| iw dev wlan0 scan {{!}} grep SSID|hostname=somimx6ul}}
:SSID: EMAC-A
{{clio| iw dev wlan0 scan {{!}} grep signal|hostname=somimx6ul}}
:signal: -78.00dBm
{{clio||hostname=somimx6ul}}
{{clos}}

<br/>
The <code>/etc/wpa_supplicant.conf</code> file will need to be modified to provide the necessary connection information, the details of which depend upon the type of encryption used for the wireless network. 
<br/>

* For an open network, uncomment the following lines in <code>/etc/wpa_supplicant.conf</code> and fill in the correct SSID for the network to which the machine should connect.
<syntaxhighlight lang=bash>
###open network
#network={
#      ssid="SSID"
#      scan_ssid=1
#       key_mgmt=NONE
#} 
</syntaxhighlight>

* Networks protected by either WEP or WPA2 encryption will need a pre-shared key (PSK), which is generated for the specific network and its password. To get the PSK, use <code>wpa_passphrase</code> with the SSID and password for the desired network as arguments. 
{{clo|indent=2}}
{{clio | indent=2 | wpa_passphrase 'your-ESSID' 'your-passphrase' {{!}} sudo tee /etc/wpa_supplicant.conf |hostname=somimx6ul}}
network={
:ssid="your-ESSID"
:&#35;psk="your-passphrase"
:psk=b99d2c0fb66194f93ad52b71051e1095dc76e12529321334b3feb18332608eb7
}
{{clos}}

* The contents of the <code>/etc/wpa_supplicant.conf</code> should now look similar to the following:
{{clo|indent=2}}
{{clio | cat /etc/wpa_supplicant.conf | hostname=somimx6ul}}
network={
:ssid="your-ESSID"
:&#35;psk="your-passphrase"
:psk=b99d2c0fb66194f93ad52b71051e1095dc76e12529321334b3feb18332608eb7
}<br />
{{clio||hostname=somimx6ul}}
{{clos}}
<br />

* The {{icli | /etc/init.d/wpa_supplicant start | hostname=somimx6ul}} command will attempt to establish a connection with the network by starting the wpa_supplicant process. <br>Use {{icli | /etc/init.d/wpa_supplicant stop | hostname=somimx6ul}} to stop the process, <br>and {{icli | /etc/init.d/wpa_supplicant restart | hostname=somimx6ul}} to restart the process.

: As the command is running, watch the terminal output for the status of the connection. A connection has been established when output stops and the last line reads:
{{clo | indent=2}}IPv6 ADDRCONF(NETDEV_CHANGE):wlan0: link becomes ready{{clos}}

:A connection has failed if output to the terminal continues and the following line is seen repeatedly:
{{clo | indent=2}}IPv6: ADDRCONF(NETDEV_UP):wlan0: link is not ready{{clos}}

:'''Successful connection''' (waiting a full minute to ensure output to the terminal stopped); <br /> 
{{clo|indent=2}}
{{clio| /etc/init.d/wpa-supplicant start| hostname=somimx6ul}}
Successfully initialized wpa_supplicant<br/>
rfkill: Cannot open RFKILL control device<br/>
{{clio| wlan0: authenticate with 1c:7e:e5:40:10:fd| hostname=somimx6ul}}
wlan0: send auth to 1c:7e:e5:40:10:fd (try 1/3)<br/>
wlan0: send auth to 1c:7e:e5:40:10:fd (try 2/3)<br/>
wlan0: authenticated<br/>
wlan0: associating with AP with corrupt beacon<br/>
wlan0: associate with 1c:7e:e5:40:10:fd (try 1/3)<br/>
wlan0: RX AssocResp from 1c:7e:e5:40:10:fd (capab=0x431 status=0 aid=6)<br/>
wlan0: associated<br/>
IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
{{clos}}
:'''Failed connection''' (waiting more than a minute as output continues to print to the terminal). The repeated lines indicate an issue establishing the connection. <br /> 
{{clo|indent=2}}
{{clio|/etc/init.d/wpa-supplicant start| hostname=somimx6ul}}
Successfully initialized wpa_supplicant                                         
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready                             
{{clio| IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready|hostname=somimx6ul}}        
cfg80211: Calling CRDA to update world regulatory domain<br/>
IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready<br/>                   
cfg80211: Calling CRDA to update world regulatory domain<br/>                   
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready<br/>                   
IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready<br/>                        
cfg80211: Calling CRDA to update world regulatory domain<br/>                   
IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready<br/>                   
IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready<br/>                        
{{clos}}
:'''A failed connection is likely the result of an improper password.''' Use <code>wpa_passphrase</code> to make sure you have the right psk for the password.
* If the wpa-supplicant successfully initializes, yet a connection is not made, use the following to ensure the interface is up:
{{clop|indent=2}}{{clio | ifup wlan0 | hostname=somimx6ul}} 
udhcpc: started, v1.31.1
udhcpc: sending discover
udhcpc: sending select for 10.0.6.116
udhcpc: lease of 10.0.6.116 obtained, lease time 28800
{{closp}}  
* The <code>ifconfig</code> command will be used to determine that the device is wirelessly connected to the network. Look to see that <code>wlan0</code> has an IP address.
{{clop|indent=2}}wlan0   Link encap:Ethernet HWaddr A8:54:B2:42:89:8D
:::inet addr:10.0.4.148 Bcast:10.0.255.255 Mask:255.255.0.0
:::UP BROADCAST RUNNING MULTICAST MTU:1500 METRIC:1
:::RX packets:3395 errors:0 dropped:6 overruns:0 frame:0
:::TX packets:60 errors:0 dropped:0 overruns:0 carrier:0
:::collisions:0 txqueuelen:1000
:::RX bytes:346619 (338.4 KiB) TX bytes:6318 (6.1 Kib){{closp}}    

* Disconnect any physical connections from the system and ping to [http://www.emacinc.com www.emacinc.com] to verify that the system can wirelessly connect to the Internet. <br />
{{clop|indent=2}}
{{cliop| ping -c 3 www.emacinc.com | hostname=somimx6ul}}
PING www.emacinc.com (172.16.0.10): 56 data bytes 
64 bytes from 172.16.0.10: seq=0 ttl=63 time=1.910 ms
64 bytes from 172.16.0.10: seq=1 ttl=63 time=1.748 ms
64 bytes from 172.16.0.10: seq=2 ttl=63 time=2.061 ms

--- www.emacinc.com ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 1.748/1.906/2.061 ms
{{cliop||hostname=somimx6ul}}{{closp}}
<br clear=all> 
</cl>
== Bluetooth ==
On the DEV-IOT6U, bluetooth is disabled by default. Enable it by:
<syntaxhighlight>gpioset gpiochip0 5=1</syntaxhighlight>
<syntaxhighlight>hciattach /dev/ttymxc3 -t 30 bcm43xx 115200 noflow</syntaxhighlight>
Use '''hciconfig''' to check that hci0 device interface is enabled, and use <syntaxhighlight>hciconfig hci0 up</syntaxhighlight> to open and initialize the HCI device. See [https://linux.die.net/man/8/hciconfig hciconfig manual] for more information on configuring your Bluetooth device.<br>
<br>
From there you have multiple different approaches to using the bluetooth device. bluetoothctl, rfcomm, etc.

===Where to Next===
*[[Bluetooth_LE_Demo_on_the_DEV-IOT6U|Bluetooth LE Demo on the DEV-IOT6U]]



== Further Information ==
:{{:Templateimpl:Navti | [[Getting_Started_with_the_DEV-IOT6U | Getting Started with the DEV-IOT6U]]}}
:{{:Templateimpl:Navti | [[Bluetooth_LE_Demo_on_the_DEV-IOT6U | Bluetooth LE Demo on the DEV-IOT6U]]}}