A lightweight image sender library for ZigBee USB sticks running the cc2531-OEPL OpenEPaperLink station firmware.
This C library acts as a serial-driver for CC2531-based ZigBee USB sticks. It can be used to transmit bi-color images to hacked supermarket price-tags via the OpenEPaperLink protocol (tested with OpenEPaperLink v1.9.0).
The data-source are generic rgb pixel-arrays, which could be fully generated in memory with no need for intermediate files.
To integrate libepaper-central in your project, head over to the docs.
The library comes with a standalone reference-program "epaperd" which picks up PPM images (P6) from a folder and sends them to nearby OpenEPaperLink displays.
The program will check for files named after tag mac addresses (e.g. 00112233aabbccdd.ppm for a tag with mac address 00:11:22:33:aa:bb:cc:dd) and falls back to default.ppm if no specific image exists for a tag – in this case the mac address will be visible on the display in addition until an applicable .ppm-file becomes available in the cache folder.
> epaperd [/cache/directory]The library is compatible with CC2531-based ZigBee USB sticks running the cc2531-OEPL station firmware.
The firmware can be obtained from Jonas Niesners OpenEPaperLink repository – for flashing there's several options available:
- Using a proprietary CC Debugger adapter
- Using a Raspberry Pi (or other single-board computer) via cc2531-flasher-pi
- Using an esp32 (see https://youtu.be/98fOzZs__fc)
libepaper-central is licensed under the MIT License.
- Pixmap format optimizations (Improved refresh speed)
- epaperd: Added command line option "
-D" to specify ZigBee radio device - epaperd: Display error message if serial device cannot be opened
- Fix: Fixed minor offset between black and red pixels
- Fix: Added fallback install dirs in CMake configuration (#1)
- Docs: Added build instructions page
- Initial version of the library
- Transmit images from generic rgb pixel-arrays
- Simple "epaperd" reference-program to load .ppm-images from a folder and transmit them to price-tags
Created by Lesosoftware in 2023