Crate max7219_driver
source · [−]Expand description
This crate provides a platform agnostic driver for the MAX7219 LED Driver IC.
This driver was built using the embedded-hal traits.
Usage
An updated version of the library should be available on crates.io. Add the following to your Cargo.toml to get is a dependency.
[dependencies]
max7219-driver = "*"
Instantiating
Create an instance of the driver with the new
method, by passing SPI and Output pin instances.
use max7219-driver::MAX7219;
let spi = // SPI instantiation code
let cs = // Output pin instantiation code
let mut max7219 = MAX7219::new(spi, cs).unwrap();
Initializing
Initialize the driver instance with the init_display
method. A boolean needs to be specified to indicate whether to clear the display after init or not.
max7219.init_display(true);
Cascading Multiple MAX7219 Devices
If you are cascading multiple devices that are driving 8x8 LED Dot Matrices instead use the MAX7219LedMat
driver as follows:
Instantiating
use max7219-driver::MAX7219LedMat;
let spi = // SPI instantiation code
let cs = // Output pin instantiation code
let mut max7219: MAX7219LedMat<_, _, BUFLEN, COUNT> = MAX7219LedMat::new(spi, cs).unwrap();
BUFLEN
should be replaced with value equivalent to the total number of pixels/LED in the cascaded displays
and COUNT
with the number of displays
Example:
If four displays are cascaded then BUFLEN
should be replaced with 256 (= 8 x 8 x 4) and COUNT
replaced with 4 resulting in
let mut max7219: MAX7219LedMat<_, _, 256, 4> = MAX7219LedMat::new(spi, cs).unwrap();
Initializing
Exactly the same as earlier, the new driver takes care of initializing all the cscaded displays.
max7219.init_display(true);