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cleanup

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This commit is contained in:
Nicholas Orlowsky 2025-03-18 18:59:58 -04:00
parent ab604f3c51
commit 6effd4f1a8
5 changed files with 129 additions and 274 deletions
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1
src/commands/mod.rs
View file

@ -221,5 +221,6 @@ func! {
/// Get service 1 PID support for $21 to $40
fn get_service_1_pid_support_2(0x01, 0x20) -> u32;
// Get the fuel level (out of 255)
fn get_fuel_level(0x01, 0x2F) -> u8;
}

134
src/device/elm327.rs
View file

@ -4,9 +4,97 @@ use std::{
io::{Read, Write},
thread, time,
};
use std::time::Duration;
use super::{Error, Obd2BaseDevice, Obd2Reader, Result};
trait SerialDevice {
fn write_all(&mut self, data: &[u8]) -> Result<()>;
fn read(&mut self, data: &mut [u8]) -> Result<usize>;
fn set_baud_rate(&mut self, baud_rate: u32) -> Result<()>;
fn purge_buffers(&mut self) -> Result<()>;
}
pub struct SerialPort {
device: Box<dyn serialport::SerialPort>
}
impl SerialPort {
pub fn new(path: &str) -> Result<Self> {
let port = serialport::new(path, 38_400)
.timeout(Duration::from_millis(10))
.parity(serialport::Parity::None)
.data_bits(serialport::DataBits::Eight)
.stop_bits(serialport::StopBits::One)
.path(path)
.open()?;
let device = SerialPort {
device: port
};
Ok(device)
}
}
impl SerialDevice for SerialPort {
fn write_all(&mut self, data: &[u8]) -> Result<()> {
Ok(self.device.write_all(data)?)
}
fn read(&mut self, data: &mut [u8]) -> Result<usize> {
Ok(self.device.read(data)?)
}
fn set_baud_rate(&mut self, baud_rate: u32) -> Result<()> {
Ok(self.device.set_baud_rate(baud_rate)?)
}
fn purge_buffers(&mut self) -> Result<()> {
Ok(self.device.clear(serialport::ClearBuffer::All)?)
}
}
pub struct FTDIDevice {
device: ftdi::Device
}
impl FTDIDevice {
pub fn new() -> Result<Self> {
let mut ftdi_device = ftdi::find_by_vid_pid(0x0404, 0x6001)
.interface(ftdi::Interface::A)
.open()?;
ftdi_device.set_baud_rate(38400)?;
ftdi_device.configure(ftdi::Bits::Eight, ftdi::StopBits::One, ftdi::Parity::None)?;
ftdi_device.usb_reset()?;
let device = FTDIDevice {
device: ftdi_device
};
Ok(device)
}
}
impl SerialDevice for FTDIDevice {
fn write_all(&mut self, data: &[u8]) -> Result<()> {
Ok(self.device.write_all(data)?)
}
fn read(&mut self, data: &mut [u8]) -> Result<usize> {
Ok(self.device.read(data)?)
}
fn set_baud_rate(&mut self, baud_rate: u32) -> Result<()> {
Ok(self.device.set_baud_rate(baud_rate)?)
}
fn purge_buffers(&mut self) -> Result<()> {
Ok(self.device.usb_purge_buffers()?)
}
}
/// An ELM327 OBD-II adapter
///
/// It communicates with the computer over UART using an FTDI FT232R USB-to-UART converter.
@ -16,13 +104,13 @@ use super::{Error, Obd2BaseDevice, Obd2Reader, Result};
///
/// [Datasheet for v1.4b](https://github.com/rsammelson/obd2/blob/master/docs/ELM327DSH.pdf), and
/// the [source](https://www.elmelectronics.com/products/dsheets/).
pub struct Elm327 {
device: ftdi::Device,
pub struct Elm327<T: SerialDevice> {
device: T,
buffer: VecDeque<u8>,
baud_rate: u32,
}
impl Obd2BaseDevice for Elm327 {
impl<T: SerialDevice> Obd2BaseDevice for Elm327<T> {
fn reset(&mut self) -> Result<()> {
self.flush_buffers()?;
self.reset_ic()?;
@ -42,7 +130,7 @@ impl Obd2BaseDevice for Elm327 {
}
}
impl Obd2Reader for Elm327 {
impl<T: SerialDevice> Obd2Reader for Elm327<T> {
fn get_line(&mut self) -> Result<Option<Vec<u8>>> {
self.get_until(b'\n', false)
}
@ -58,22 +146,12 @@ impl Obd2Reader for Elm327 {
}
}
impl Elm327 {
fn new() -> Result<Self> {
let mut ftdi_device = ftdi::find_by_vid_pid(0x0404, 0x6001)
.interface(ftdi::Interface::A)
.open()?;
ftdi_device.set_baud_rate(38400)?;
ftdi_device.configure(ftdi::Bits::Eight, ftdi::StopBits::One, ftdi::Parity::None)?;
// device.set_latency_timer(2).unwrap();
ftdi_device.usb_reset()?;
impl<T: SerialDevice> Elm327<T> {
pub fn new(serial_device: T) -> Result<Self> {
let mut device = Elm327 {
device: ftdi_device,
device: serial_device,
buffer: VecDeque::new(),
baud_rate: 38400,
baud_rate: 38_400,
};
device.connect(false)?;
@ -92,7 +170,7 @@ impl Elm327 {
}
fn flush_buffers(&mut self) -> Result<()> {
self.device.usb_purge_buffers()?;
self.device.purge_buffers()?;
Ok(())
}
@ -117,9 +195,10 @@ impl Elm327 {
fn reset_ic(&mut self) -> Result<()> {
info!("Performing IC reset");
self.send_serial_str("ATZ")?;
let response = self.get_response()?;
debug!(
"reset_ic: got response {:?}",
self.get_response()?
response
.as_ref()
.map(|l| std::str::from_utf8(l.as_slice()))
);
@ -128,14 +207,18 @@ impl Elm327 {
fn reset_protocol(&mut self) -> Result<()> {
info!("Performing protocol reset");
let elm_response = self.serial_cmd("ATSP0")?;
debug!(
"reset_protocol: got response {:?}",
self.serial_cmd("ATSP0")?
elm_response
);
let obd_response = self.cmd(&[0x01, 0x00])?;
debug!(
"reset_protocol: got OBD response {:?}",
self.cmd(&[0x01, 0x00])?
obd_response
);
self.flush_buffers()?;
Ok(())
}
@ -252,7 +335,8 @@ impl Elm327 {
fn read_into_queue(&mut self) -> Result<()> {
let mut buf = [0u8; 16];
loop {
let len = self.device.read(&mut buf)?;
let len_res = self.device.read(&mut buf);
if let Ok(len) = len_res {
if len > 0 {
self.buffer.extend(&buf[0..len]);
trace!(
@ -263,6 +347,10 @@ impl Elm327 {
trace!("read_into_queue: no values left to read");
break;
}
} else {
trace!("read_into_queue: no values left to read");
break;
}
}
Ok(())
}

240
src/device/elm327_linux.rs
View file

@ -1,240 +0,0 @@
use log::{debug, info, trace};
use std::{
collections::VecDeque,
io::{Read, Write},
thread, time,
};
use std::time::Duration;
use super::{Error, Obd2BaseDevice, Obd2Reader, Result};
/// An ELM327 OBD-II adapter
///
/// Uses a /dev/ttyUSB* device or similar to communicate
pub struct Elm327Linux {
port: Box<dyn serialport::SerialPort>,
buffer: VecDeque<u8>,
baud_rate: u32,
}
impl Obd2BaseDevice for Elm327Linux {
fn reset(&mut self) -> Result<()> {
self.flush_buffers()?;
self.reset_ic()?;
thread::sleep(time::Duration::from_millis(500));
self.reset_protocol()?;
Ok(())
}
fn send_cmd(&mut self, data: &[u8]) -> Result<()> {
trace!("send_cmd: sending {:?}", std::str::from_utf8(data));
self.send_serial_str(
data.into_iter()
.flat_map(|v| format!("{:02X}", v).chars().collect::<Vec<char>>())
.collect::<String>()
.as_str(),
)
}
}
impl Obd2Reader for Elm327Linux {
fn get_line(&mut self) -> Result<Option<Vec<u8>>> {
self.get_until(b'\n', false)
}
/// Read data until the ELM327's prompt character is printed
///
/// This will receive the entire OBD-II response. The prompt signifies that the ELM327 is ready
/// for another command. If this is not called after each OBD-II command is sent, the prompt
/// character will come out of the receive queue later and because it is not valid hex this
/// could cause problems. If a timeout occurs, `Ok(None)` will be returned.
fn get_response(&mut self) -> Result<Option<Vec<u8>>> {
self.get_until(b'>', true)
}
}
impl Elm327Linux {
pub fn new(serial_path: &str) -> ::anyhow::Result<Self> {
let port = serialport::new(serial_path, 38_400)
.timeout(Duration::from_millis(10))
.parity(serialport::Parity::None)
.data_bits(serialport::DataBits::Eight)
.stop_bits(serialport::StopBits::One)
.path(serial_path)
.open()?;
let mut device = Elm327Linux {
port,
buffer: VecDeque::new(),
baud_rate: 38_400,
};
Ok(device)
}
/// Flush the device's buffer
pub fn flush(&mut self) -> Result<()> {
thread::sleep(time::Duration::from_millis(500));
self.read_into_queue()?;
self.buffer.clear();
thread::sleep(time::Duration::from_millis(500));
Ok(())
}
fn connect(&mut self) -> Result<()> {
thread::sleep(time::Duration::from_millis(500));
self.serial_cmd(" ")?;
thread::sleep(time::Duration::from_millis(500));
self.reset()?;
Ok(())
}
fn reset_ic(&mut self) -> Result<()> {
info!("Performing IC reset");
self.send_serial_str("ATZ")?;
self.get_response()?;
//debug!(
// "reset_ic: got response {:?}",
// self.get_response()?
// .as_ref()
// .map(|l| std::str::from_utf8(l.as_slice()))
//);
Ok(())
}
fn flush_buffers(&mut self) -> Result<()> {
self.buffer.flush();
Ok(())
}
fn reset_protocol(&mut self) -> Result<()> {
info!("Performing protocol reset");
self.serial_cmd("ATSP0")?;
//debug!(
// "reset_protocol: got response {:?}",
// self.serial_cmd("ATSP0")?
//);
self.cmd(&[0x01, 0x00])?;
//debug!(
// "reset_protocol: got OBD response {:?}",
// self.cmd(&[0x01, 0x00])?
//);
self.flush_buffers()?;
Ok(())
}
fn get_until(&mut self, end_byte: u8, allow_empty: bool) -> Result<Option<Vec<u8>>> {
const TIMEOUT: time::Duration = time::Duration::from_secs(5);
trace!("get_until: getting until {}", end_byte);
let mut buf = Vec::new();
let start = time::Instant::now();
while start.elapsed() < TIMEOUT {
trace!("Getting Byte");
let Some(b) = self.get_byte()? else { continue };
trace!("{}", b);
let b = match b {
b'\r' => Some(b'\n'),
b'\n' => None, // no push here
_ => Some(b),
};
if let Some(b) = b {
buf.push(b);
if b == end_byte {
break;
}
}
}
trace!(
"get_until: got {:?} ({:?})",
buf,
std::str::from_utf8(buf.as_slice())
);
match buf.pop() {
Some(b) if b == end_byte => {
trace!("got it!");
if allow_empty || !buf.is_empty() {
Ok(Some(buf))
} else {
// empty line, try again
self.get_until(end_byte, allow_empty)
}
} // we got it
Some(f) => {
// incomplete line read
for b in buf.iter().rev() {
self.buffer.push_front(*b);
}
self.buffer.push_front(f);
Ok(None)
}
None => Ok(None),
}
}
fn get_byte(&mut self) -> Result<Option<u8>> {
match self.buffer.pop_front() {
Some(b'\0') => Ok(None),
Some(b) => Ok(Some(b)),
None => {
trace!("EmptyBuf");
self.read_into_queue()?;
Ok(None)
}
}
}
fn read_into_queue(&mut self) -> Result<()> {
let mut buf = [0u8; 16];
loop {
let len_res = self.port.read(&mut buf);
if let Ok(len) = len_res {
if len > 0 {
self.buffer.extend(&buf[0..len]);
trace!(
"read_into_queue: values {:?}",
std::str::from_utf8(&buf[0..len])
);
} else {
trace!("read_into_queue: no values left to read");
break;
}
} else {
trace!("read_into_queue: no values left to read");
break;
}
}
Ok(())
}
fn serial_cmd(&mut self, cmd: &str) -> Result<Option<String>> {
self.send_serial_str(cmd)?;
self.get_response()
.map(|o| o.and_then(|resp| String::from_utf8(resp).ok()))
}
/// Function for sending a raw string, without encoding into ASCII hex
fn send_serial_str(&mut self, data: &str) -> Result<()> {
trace!("send_serial_str: sending {:?}", data);
let data = data.as_bytes();
self.port.write_all(data)?;
self.port.write_all(b"\r\n")?;
let line = self.get_line()?;
if line.as_ref().is_some_and(|v| v == data) {
Ok(())
} else {
Err(Error::Communication(format!(
"send_serial_str: got {:?} instead of echoed command ({:?})",
line, data
)))
}
}
}

14
src/device/mod.rs
View file

@ -1,10 +1,7 @@
//! Lower level OBD-II interfacing structures
mod elm327;
pub use elm327::Elm327;
mod elm327_linux;
pub use elm327_linux::Elm327Linux;
pub use elm327::{Elm327, SerialPort, FTDIDevice};
type Result<T> = std::result::Result<T, Error>;
@ -57,6 +54,9 @@ pub enum Error {
#[error("FTDI error: `{0:?}`")]
Ftdi(ftdi::Error),
#[error("Serialport error: `{0:?}`")]
Serialport(serialport::Error),
/// An I/O error in a low-level [std::io] stream operation
#[error("IO error: `{0:?}`")]
IO(std::io::Error),
@ -72,6 +72,12 @@ impl From<ftdi::Error> for Error {
}
}
impl From<serialport::Error> for Error {
fn from(e: serialport::Error) -> Self {
Error::Serialport(e)
}
}
impl From<std::io::Error> for Error {
fn from(e: std::io::Error) -> Self {
Error::IO(e)

2
src/interface.rs
View file

@ -41,7 +41,7 @@ impl<T: Obd2BaseDevice> Obd2Device for Obd2<T> {
impl<T: Obd2BaseDevice> Obd2<T> {
pub fn new(dev: T) -> ::anyhow::Result<Self> {
let mut device = Obd2 {
let device = Obd2 {
device: dev
};