Playing with shift registers with Rust + ARMv7 + GPIO

shift_register.rs

extern crate sysfs_gpio;

use sysfs_gpio::{Direction,Pin};
use std::time::Duration;
use std::thread::sleep;

fn main() {
    let data_pin = Pin::new(18);  // SER   #14
    let latch_pin = Pin::new(23); // RCLK  #12
    let clock_pin = Pin::new(24); // SRCLK #11

    let mut serial_value = 0;

    data_pin.export().unwrap();
    latch_pin.export().unwrap();
    clock_pin.export().unwrap();

    // Let's give udev rules the time to get applied
    sleep(Duration::from_millis(1000));

    data_pin.set_direction(Direction::Low).unwrap();
    latch_pin.set_direction(Direction::Low).unwrap();
    clock_pin.set_direction(Direction::Low).unwrap();

    for _ in 0..16 {
        serial_value = 1;
        println!("{}", serial_value);

        latch_pin.set_value(0).unwrap();
        data_pin.set_value(serial_value).unwrap();
        clock_pin.set_value(1).unwrap();
        clock_pin.set_value(0).unwrap();
        latch_pin.set_value(1).unwrap();

        sleep(Duration::from_millis(500));
    }

    for _ in 0..16 {
        serial_value = 0;
        println!("{}", serial_value);

        latch_pin.set_value(0).unwrap();
        data_pin.set_value(serial_value).unwrap();
        clock_pin.set_value(1).unwrap();
        clock_pin.set_value(0).unwrap();
        latch_pin.set_value(1).unwrap();

        sleep(Duration::from_millis(500));
    }

    data_pin.unexport().unwrap();
    latch_pin.unexport().unwrap();
    clock_pin.unexport().unwrap();

    println!("Done.");
}