ethercat-plc 0.2.1

Tools to build a PLC like program using the ethercat crate
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// Part of ethercat-rs. Copyright 2018-2023 by the authors.
// This work is dual-licensed under Apache 2.0 and MIT terms.

use byteorder::{ByteOrder, NativeEndian as NE};

pub const MAGIC: f32 = 2015.02;

pub const RESET: u16 = 0x0000;
pub const IDLE:  u16 = 0x1000;
pub const WARN:  u16 = 0x3000;
pub const START: u16 = 0x5000;
pub const BUSY:  u16 = 0x6000;
pub const STOP:  u16 = 0x7000;
pub const ERROR: u16 = 0x8000;

#[repr(C)]
#[derive(Default)]
pub struct DiscreteOutput {
    pub value:  i16,
    pub target: i16,
    pub status: u16,
}

#[repr(C)]
#[derive(Default)]
pub struct FlatOutput1 {
    pub value:  f32,
    pub target: f32,
    pub status: u16,
    pub aux:    u16,
    pub param1: f32,
}

pub fn copy_string(dst: &mut [u16], src: &str) {
    let mut nbytes = src.len().min(dst.len() * 2);
    let mut src_vec;
    let src = if nbytes % 2 == 1 {
        src_vec = src.to_string();
        src_vec.push('\0');
        nbytes += 1;
        &src_vec
    } else {
        src
    };
    NE::read_u16_into(src[..nbytes].as_bytes(), &mut dst[..nbytes/2])
}

pub fn copy_float(dst: &mut [u16], f: f32) {
    let mut buf = [0u8; 4];
    NE::write_f32(&mut buf, f);
    NE::read_u16_into(&buf, &mut dst[..2]);
}