1 use std::io::{self, Write};
2 use std::time::Duration;
3
4 use clap::{Arg, Command};
5
6 use serialport::{DataBits, StopBits};
7
main()8 fn main() {
9 let matches = Command::new("Serialport Example - Heartbeat")
10 .about("Write bytes to a serial port at 1Hz")
11 .disable_version_flag(true)
12 .arg(
13 Arg::new("port")
14 .help("The device path to a serial port")
15 .required(true),
16 )
17 .arg(
18 Arg::new("baud")
19 .help("The baud rate to connect at")
20 .use_value_delimiter(false)
21 .required(true)
22 .validator(valid_baud),
23 )
24 .arg(
25 Arg::new("stop-bits")
26 .long("stop-bits")
27 .help("Number of stop bits to use")
28 .takes_value(true)
29 .possible_values(["1", "2"])
30 .default_value("1"),
31 )
32 .arg(
33 Arg::new("data-bits")
34 .long("data-bits")
35 .help("Number of data bits to use")
36 .takes_value(true)
37 .possible_values(["5", "6", "7", "8"])
38 .default_value("8"),
39 )
40 .arg(
41 Arg::new("rate")
42 .long("rate")
43 .help("Frequency (Hz) to repeat transmission of the pattern (0 indicates sending only once")
44 .takes_value(true)
45 .default_value("1"),
46 )
47 .arg(
48 Arg::new("string")
49 .long("string")
50 .help("String to transmit")
51 .takes_value(true)
52 .default_value("."),
53 )
54 .get_matches();
55
56 let port_name = matches.value_of("port").unwrap();
57 let baud_rate = matches.value_of("baud").unwrap().parse::<u32>().unwrap();
58 let stop_bits = match matches.value_of("stop-bits") {
59 Some("2") => StopBits::Two,
60 _ => StopBits::One,
61 };
62 let data_bits = match matches.value_of("data-bits") {
63 Some("5") => DataBits::Five,
64 Some("6") => DataBits::Six,
65 Some("7") => DataBits::Seven,
66 _ => DataBits::Eight,
67 };
68 let rate = matches.value_of("rate").unwrap().parse::<u32>().unwrap();
69 let string = matches.value_of("string").unwrap();
70
71 let builder = serialport::new(port_name, baud_rate)
72 .stop_bits(stop_bits)
73 .data_bits(data_bits);
74 println!("{:?}", &builder);
75 let mut port = builder.open().unwrap_or_else(|e| {
76 eprintln!("Failed to open \"{}\". Error: {}", port_name, e);
77 ::std::process::exit(1);
78 });
79
80 println!(
81 "Writing '{}' to {} at {} baud at {}Hz",
82 &string, &port_name, &baud_rate, &rate
83 );
84 loop {
85 match port.write(string.as_bytes()) {
86 Ok(_) => {
87 print!("{}", &string);
88 std::io::stdout().flush().unwrap();
89 }
90 Err(ref e) if e.kind() == io::ErrorKind::TimedOut => (),
91 Err(e) => eprintln!("{:?}", e),
92 }
93 if rate == 0 {
94 return;
95 }
96 std::thread::sleep(Duration::from_millis((1000.0 / (rate as f32)) as u64));
97 }
98 }
99
valid_baud(val: &str) -> std::result::Result<(), String>100 fn valid_baud(val: &str) -> std::result::Result<(), String> {
101 val.parse::<u32>()
102 .map(|_| ())
103 .map_err(|_| format!("Invalid baud rate '{}' specified", val))
104 }
105