neso 0.5.0

An NES emulator.
Documentation 
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#[cfg(not(target_arch = "wasm32"))]
use serde_derive::{Deserialize, Serialize};
use std::cmp;

#[derive(Default)]
#[cfg_attr(not(target_arch = "wasm32"), derive(Deserialize, Serialize))]
pub struct Controller {
    // A, B, Select, Start, Up, Down, Left, Right
    value: u8,
    index: u8,
    strobe: bool,
}

impl Controller {
    pub fn write_strobe(&mut self, val: bool) {
        self.strobe = val;
        if self.strobe {
            self.index = 0;
        }
    }

    pub fn read_value(&mut self) -> u8 {
        let ret = self.value.wrapping_shr(u32::from(self.index)) & 0x01;
        self.index = cmp::min(self.index + 1, 8);
        if self.strobe {
            self.index = 0;
        }
        ret
    }

    pub fn press_button(&mut self, index: u8) {
        self.value |= 1 << index;
    }

    pub fn release_button(&mut self, index: u8) {
        self.value &= !(1 << index);
    }
}