Screen with width not divisible by 8 require special care when allocating the buffer and when handling rotation. Define a function for getting the needed buffer size (round up to next byte). Change how rotation is done by changing coordinates instead of direct pixel access.
|3 years ago|
|.github/workflows||3 years ago|
|examples||3 years ago|
|src||3 years ago|
|.gitignore||5 years ago|
|.travis.yml||3 years ago|
|CHANGELOG.md||3 years ago|
|Cargo.toml||3 years ago|
|License.md||5 years ago|
|README.md||3 years ago|
This library contains a driver for E-Paper Modules from Waveshare (which are basically the same as the Dalian Good Display ones).
It uses the embedded graphics library for the optional graphics support.
A 2018-edition compatible version (Rust 1.31+) is needed.
Other similiar libraries with support for much more displays are u8g2 and GxEPD for arduino.
There are multiple examples in the examples folder. Use
cargo run --example example_name to try them.
// Setup the epd let mut epd = EPD4in2::new(&mut spi, cs, busy, dc, rst, &mut delay)?; // Setup the graphics let mut display = Display4in2::default(); // Draw some text display.draw( let _ = Text::new("Hello Rust!", Point::new(x, y)) .into_styled(text_style!( font = Font12x16, text_color = Black, background_color = White )) .draw(display); ); // Transfer the frame data to the epd and display it epd.update_and_display_frame(&mut spi, &display.buffer())?;
|Device (with Link)||Colors||Flexible Display||Partial Refresh||Supported||Tested|
|7.5 Inch B/W V2 (A) ||Black, White||✕||✕||✔||✔|
|7.5 Inch B/W (A)||Black, White||✕||✕||✔||✔|
|4.2 Inch B/W (A)||Black, White||✕||Not officially ||✔||✔|
|1.54 Inch B/W (A)||Black, White||✕||✔||✔||✔|
|2.13 Inch B/W (A)||Black, White||✕||✔|
|2.9 Inch B/W (A)||Black, White||✕||✔||✔||✔|
|1.54 Inch B/W/R (B)||Black, White, Red||✕||✕||✔||✔|
|2.9 Inch B/W/R (B/C)||Black, White, Red||✕||✕||✔||✔|
: 7.5 Inch B/W V2 (A)
Since November 2019 Waveshare sells their updated version of these displays. They should have a "V2" marking sticker on the backside of the panel.
epd7in5_v2 instead of
epd7in5, because the protocol changed.
: 4.2 Inch E-Ink Black/White - Partial Refresh
Out of the Box the original driver from Waveshare only supports full updates.
That means: Be careful with the quick refresh updates:
It's possible with this driver but might lead to ghosting / burn-in effects therefore it's hidden behind a feature.
|CS||SPI chip select (Low active)|
|DC||Data/Command control pin (High for data, and low for command)|
|RST||External reset pin (Low for reset)|
|BUSY||Busy state output pin (Low for busy)|
There are two types of Display Configurations used in Wavedshare EPDs, which also needs to be set on the "new" E-Paper Driver HAT. They are also called A and B, but you shouldn't get confused and mix it with the Type A,B,C and D of the various Displays, which just describe different types (colored variants) or new versions. In the Display Config the seperation is most likely due to included fast partial refresh of the displays. In a Tabular form:
|Type A||Tybe B|
|1.54in (A)||1.54in (B)|
|2.13in (A)||1.54in (C)|
|2.13in (D)||2.13in (B)|
|2.9in (A)||2.13in (C)|