Linux Driver

The code in this repository acts as a Linux interface for controlling JURA coffee makers over a serial (UART) connection. Once running, the following file-interface will be exposed:

/
├── tmp
│   ├── coffee_maker
│   │   ├── tx
│   │   ├── rx
│   │   ├── status
│   │   ├── mode
│   │   └── device
│   └── ...
└── ...

• tx is a FIFO named pipe where you can write stuff to, to send it to the coffee maker.
• rx is a FIFO named pipe where you can read stuff from, that gets send from the coffee maker.
• status is a simple text file containing the status of the connection (1 == Running).
• mode is a simple text file containing the current operation mode. Currently just a placeholder for the future.
• device is a simple text file containing the device name of the connected coffee maker (e.g. EF532M V02.03).

Requirements

The following requirements are required to build this project.

• A C++20 compatible compiler like gcc or clang
• The build system is written using CMake
• For managing dependencies in CMake, we are using conan

Fedora

To install those dependencies on Fedora, run the following commands:

sudo dnf install -y gcc clang cmake python3 python3-pip
pip3 install --user conan

Raspberry Pi

To install those dependencies on a Raspberry Pi, running the Raspberry Pi OS, run the following commands:

sudo apt install -y cmake python3 python3-pip
pip3 install --user conan

For all the other requirements, head over here: https://github.com/Jutta-Proto/hardware-pi#raspberry-pi-os

Building

Run the following commands to build this project:

# Clone the repository:
git clone https://github.com/Jutta-Proto/linux-diver.git
# Switch into the newly cloned repository:
cd linux-driver
# Build the project:
mkdir build
cd build
cmake ..
cmake --build .

Usage

From inside the build directory, you can execute the driver with the following command:

./src/Jutta_Driver /dev/tty0

Here /dev/tty0 is the path to the serial port, you are using. In case you are running this on a Raspberry Pi, and you connected like described here, it should be /dev/tty0.

Example

The following example shows how to read from a FIFO named pipe.

import os
import errno

FIFO = "/tmp/coffee_maker/rx"

try:
    os.mkfifo(FIFO)
except OSError as oe:
    if oe.errno != errno.EEXIST:
        raise

while True:
    print("Opening FIFO...")
    with open(FIFO) as fifo:
        print("FIFO opened")
        while True:
            data = fifo.read()
            if len(data) == 0:
                print("Writer closed")
                break
            print('Read: "{0}"'.format(data))

Source: https://stackoverflow.com/a/39089792