A small collection of conveninence code for my personal experiments with the RPi.

Clone the repo:

git clone https://github.com/ephsmith/rpi.git

Change to the top-level repo dir and install using pip3:

cd rpi && pip3 install .

virtualenvwrapper is probably the fastest way to start using Python virtual environments if you aren’t already.

The
Basic Installation guide
is a great place to start. However…

If you prefer not to follow the install guide, these commands will
get you up and running quickly on the RaspberryPi:

sudo pip3 install virtualenv virtualenvwrapper
echo "export WORKON_HOME=~/.virtualenvs" >> ~/.bashrc
echo "source /usr/local/bin/virtualenvwrapper.sh" >> ~/.bashrc
source ~/.bashrc

For RaspberryPi projects, its best to configure your virtual environment to use site-packages so that modules like RPi.GPIO are still accessible. Modules here require RPi.GPIO. Create the virtual env like so:

mkvirtualenv --python=python3 --system-site-packages <env-name-here>

virtualenvwrapper will create the virtualenv directory under the
WORKON_HOME directory and activate it. Your prompt should indicate
this with the env name in parens–like so:

(env-name-here) user@pi$

Change to the top-level project directory and run

pip install .

Here’s an example that imports the ussensor module and reads a distance measurement.

from rpi.ussensor import ussensor

sensor = ussensor(echo=17, trigger=4, poll=True)
print(sensor.distance())

Note: If you installed into a virtual environment, you’ll need to
activate the venv prior to executing the script.

The Arm class is currently useful for the LynxMotion AL5B/SSC-23U
combination. Here’s an example:

from rpi.arm import Arm
import serial

com = serial.Serial('/dev/ttyUSB0', 9600)
a = Arm(com=com)

# Set all servo positions to midpoint on the AL5B
a.move()

Here’s a quick example that interfaces a NewHaven LCD display and
reports a message:

import serial
from rpi.lcd import lcd

com = serial.Serial('/dev/ttyS0', 9600)
disp = lcd(com=com)

disp.display_clear()
disp.text('Hello World')

Examples are available under the examples directory.