epd-driver for 2.7" display
The E-Paper display driver written in C from Embedded Artists is modified to be used with Colibri VF50 module on Viola V1.1 from Toradex®.
Works on Linux
| Viola Pins | Pins | Description | Description | Pin | Viola Pins |
|---|---|---|---|---|---|
| 7 | 1 | GND | 3v3 | 2 | 4 |
| 22 | 3 | SLCK | MOSI | 4 | 20 |
| 21 | 5 | MISO | SSEL | 6 | 23 |
| 34 | 7 | BUSY | BORDER | 8 | 37 |
| NC | 9 | SCL | SDA | 10 | NC |
| NC | 11 | PWM | RESET | 12 | 39 |
| 36 | 13 | PANEL ON | DISCHARGE | 14 | 38 |
NC Not connected to Viola Board
The following changes were required to be made for the E-Paper display interface.
5 GPIO were required for the interface. The SPI was already in the default dtb configuration. Since the resources needed the modifications, a patch is created for additional reference. For this implementation UART1 and UART2 is scavanged. While the CAN1 is introduced for need of application not dependent on E-Paper Display.
The project is editied using visual studio code with following plugins:
- C/C++ extension from Microsoft™.
- CMake language support plugin from twxs.
- CMake language support plugin from vector-of-bool.
The compiler tools are
- ARM compiler toolchain for Toradex boards as described in this page.
There are 3 project targets:
This generates the fuse library enabled part that will be later used as a /dev/epd device using FUSE as discussed in the original Embedded Artists repository.
- The board had to be updated with the necessary FUSE library using "opkg install fuse".
- The cross compilation needs definition of _FILE_OFFSET_BITS=64 during linking FUSE library.
The test program that is already part of Embedded Artists code and toggles the various images from the "image" folder after 5 seconds. The /dev/epd need not be installed for this to work.
The application program which is specific. The intention is to update the connected interface and it's ethernet IP on the display every minute using cron. Thus whenever the device is connected to network, the IP always is available to ssh in the device.
The fonts required are used from openglcd.
This is a target application that only tests if the IP search is working and buffer handling is OK.
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