Before we can start sending IP packets to and from our microcontroller board we have to connect it to an IP network.
For this we will be using WiFi.
If you, for example by using your phone,
scan for WiFi networks near the lab
you should find a few networks with names
These networks are spanned by the Raspberry Pis
on your desks.
To find out which of these networks belongs to your Pi you can execute the following command:
[user@computer ~]$ cat /etc/hostapd/hostapd.conf interface=wint0 driver=nl80211 channel=1 wpa=2 ssid=nota_x wpa_passphrase=password_x
Of particular interest are the last two lines containing the name of the WiFi network and its password.
Next we will create a new NodeMCU project for this chapter and use the WiFi credentials to connect to the network.
First create the new project:
[user@computer ~]$ cd projects [user@computer ~]$ cp -rv /usr/src/nodemcu_base projects/chapter_2a [user@computer ~]$ cd projects/chapter_2a
Then use the text editor to open the
file in your new project.
After uncommenting the two lines in this file
and entering the WiFi name and Password
the file should look something like this:
[user@computer ~]$ cat credentials.lua SSID= "nota_x" PASSWORD= "password_x"
We can now upload the project to the project to the microcontroller like before:
[user@computer ~]$ nodemcu-uploader --port /dev/ttyUSB0 upload *.lua
When you now attach to the output of the microcontroller using picocom and press the reset button you should get messages like the below, showing that connecting to the WiFi network was sucessful.
[user@computer ~]$ picocom -b 115200 /dev/ttyUSB0 init: connecting to AP: nota_1 init: retrying connection 2/75 init: connected to AP: nota_1 init: got IP address 192.168.94.158 via DHCP init: startup will continue in 3s init: handing over to application Hello from your NodeMCU application! Hi from your NodeMCU application!