View source for Howto setup Raspbian for serial read



This howto will cover the steps to setup a Rasperrypi for reading CSV stream from RPICT series board.

=Hardware and OS=
This applies to all Raspberrypi.

Tested with OS: <br>
Raspbian Jessie '''2017-06-21-raspbian-jessie.img'''<br>
Raspbian Stretch '''2017-09-07-raspbian-stretch-lite.img'''<br>
Raspbian Stretch '''2018-06-27-raspbian-stretch-lite.img'''<br>
Raspbian Stretch '''2018-10-09-raspbian-stretch-lite.img'''<br>
Raspbian Stretch '''2018-11-13-raspbian-stretch-lite.img'''<br>
Raspbian Buster  '''2019-06-20-raspbian-buster-lite.img''' <br>
Raspbian Buster  '''2020-02-13-raspbian-buster-lite.img''' <br>

If the image from Emoncms (emonpi) is used then this setup is not needed.

=Steps=

==-1-==

Download the image from the raspberrypi website.
https://www.raspberrypi.org/downloads/raspbian/

==-2-==

Write the image to the SD card. Follow instructions given by the raspberrypi website.

https://www.raspberrypi.org/documentation/installation/installing-images/

==-3-==

Once the image written create an empty file called 'ssh' in the boot section of the image.

==-4-==

Power up the raspberrypi and connect it to the ethernet network. <br>
Access the raspberrypi with ssh.<br>

===Linux based OS===
This is as simple as issuing.<br>
 $ ssh pi@raspberrypi

<small>Use password raspberry</small>

===On other systems (windows, ios)===
We recommend to use the putty tool. [https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html Download here]<br>
As above use<br>
hostname: raspberrypi<br>
user: pi<br>
password: raspberry<br>

This will give you access to a terminal window in which you can issue commands on the raspberrypi.

==-5-==
Run the raspi-config tool
 $ sudo raspi-config

Then disable the login uart
 5 Interfacing Options
 P6 Serial

Select '''No''' to the login shell question.<br>
Select '''Yes''' to the serial port hardware to be enabled question.<br>

Select '''Ok''' at the summary.

Back at the menu select '''finish'''.

Select '''No''' to the reboot question (we will do that later).<br>

==-6-==
[OPTIONAL]<br>
Update the Raspbian OS.
 sudo apt-get update

==-7-==
Edit the /boot/config.txt file
 $ sudo nano /boot/config.txt

At the end of the file add the following line:
 dtoverlay=pi3-disable-bt
<small>(note the above will disable bluetooth - if bluetooth is needed do not execute this step and use ttyS0 instead of ttyAMA0 for what follows).<br>
A one liner of the above command would be<br>
sudo bash -c 'echo "dtoverlay=pi3-disable-bt" >> /boot/config.txt'
</small>

Save and Exit file.

==-8-==
[OPTIONAL]<br>
Disable hciuart
 sudo systemctl disable hciuart

==-9-==
Reboot
 sudo reboot & exit
return to the ssh session again once the raspberrypi up and running again.

==-10-==
Insert the RPICT board on the RPI. Configure and read from serial port
 stty -F /dev/ttyAMA0 raw speed 38400
 cat /dev/ttyAMA0

==-11-==
[OPTIONAL]
It might be useful to get the board with all utilities ready at this point. Just issue the commands below:
 sudo apt-get install python-serial
 wget lechacal.com/RPICT/tools/lcl-rpict-config.py.zip
 unzip lcl-rpict-config.py.zip
 sudo mv lcl-rpict-config.py /usr/local/bin