max7219

A platform agnostic driver to interface with the MAX7219 (LED display driver)

What works

• Powering on/off the MAX chip
• Basic commands for setting LEDs on/off.
• Chaining support (max 8 devices)

Example

Here is a simple example for using the MAX7219 on a hifive1-revb device with e310x_hal: ```rust

![no_std]

![no_main]

extern crate panic_halt;

use riscv_rt::entry; use hifive1::hal::prelude::; use hifive1::hal::e310x::Peripherals; use max7219::;

[entry]

fn main() -> ! { let p = Peripherals::take().unwrap();

// Configure clocks
hifive1::clock::configure(p.PRCI, p.AONCLK, 320.mhz().into());

// Configure SPI pins
let mut gpio = p.GPIO0.split();

let data = gpio.pin3.into_output(&mut gpio.output_en, &mut gpio.drive,
                                 &mut gpio.out_xor, &mut gpio.iof_en);
let sck = gpio.pin5.into_output(&mut gpio.output_en, &mut gpio.drive,
                                &mut gpio.out_xor, &mut gpio.iof_en);
let cs = gpio.pin2.into_output(&mut gpio.output_en, &mut gpio.drive,
                               &mut gpio.out_xor, &mut gpio.iof_en);

let mut display = MAX7219::new(1, data, cs, sck).unwrap();

// make sure to wake the display up
display.power_on().unwrap();
// write given octet of ASCII characters
display.write_str(0, b"pls help").unwrap();
// set display intensity lower
display.set_intensity(0, 0x1).unwrap();

loop {}

} ```

Credits

Original work by Maikel Wever. Adapted to latest embedded-hal and documented by Ales Katona.

License

Licensed under MIT license (LICENSE or http://opensource.org/licenses/MIT)