Howto setup Raspbian for serial read

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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:
Raspbian Jessie 2017-06-21-raspbian-jessie.img
Raspbian Stretch 2017-09-07-raspbian-stretch-lite.img
Raspbian Stretch 2018-06-27-raspbian-stretch-lite.img
Raspbian Stretch 2018-10-09-raspbian-stretch-lite.img
Raspbian Stretch 2018-11-13-raspbian-stretch-lite.img
Raspbian Buster 2019-06-20-raspbian-buster-lite.img
Raspbian Buster 2020-02-13-raspbian-buster-lite.img

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.
Access the raspberrypi with ssh.

Linux based OS

This is as simple as issuing.

$ ssh pi@raspberrypi

Use password raspberry

On other systems (windows, ios)

We recommend to use the putty tool. Download here
As above use
hostname: raspberrypi
user: pi
password: raspberry

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.
Select Yes to the serial port hardware to be enabled question.

From the menu finish the raspi-config.

Select No to the reboot question (we will do that later).

-6-

[OPTIONAL]
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

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

Save and Exit file.

-8-

[OPTIONAL]
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 cp lcl-rpict-config.py /usr/local/bin