colin-nolan/remote-eink

A server that can be used to remotely control a display, such as eink screen

Remote eInk

A server that can be used to remotely control a display, such as eink screen.

OpenAPI

The OpenAPI specification can be viewed here: https://colin-nolan.github.io/remote-eink/swagger-ui/

Troubleshooting

RPi.GPIO gcc10 issue

A generic error when compiling RPi.GPIO may be caused by a change in gcc10:

collect2: error: ld returned 1 exit status
error: command '/usr/bin/arm-linux-gnueabihf-gcc' failed with exit code 1

It can be avoided by setting CFLAGS, e.g.:

CFLAGS="-fcommon" poetry install

Development

Implementation

FlaskApp app:

• Takes multiple DisplayController instances.
• Is associated to AppData.
• AppData stores the DisplayController instances. It provides a CommunicationPipe through which write operations to the data must be made in requests (as requests may be handled by different processes).

Server:

• Operates a FlaskApp app.
• Can be used with run (blocking) or start (non-blocking).

A DisplayController:

• Controls the display of an Image within a ImageStore using a DisplayDriver.
• Knows what the current_image being displayed is.
• May apply transformations to the image using ImageTransformerSequence.
• Has ListenableDisplayController, CyclableDisplayController, and SleepyDisplayController variants.

An Image:

• Allows access to data representing an image.
• Is of a particular type (e.g. png).

An ImageTransformer:

• Takes an Image and modifies it to produce a variation (e.g. a rotated copy of the image).
• Multiple transformers can be put together using an ImageTransformerSequence.
• Applied to all images (e.g. when display is rotated, all images can be rotated).

A DisplayDriver:

• A driver for a display device.
• Can set an image to be displayed; clear the display; sleep/wake the display.

Legal

AGPL v3.0. Copyright 2020, 2021, 2022 Colin Nolan.

This work is in no way related to the company that I work for.