Crate atat

source ·
Expand description

A helper crate to abstract away the state management and string parsing of AT command communication.

It works by creating structs for each AT command, that each implements AtatCmd. With corresponding response structs that each implements AtatResp.

This can be simplified alot using the atat_derive crate!

§Examples

§Command and response example without atat_derive:

use atat::{AtatCmd, AtatResp, Error, InternalError};
use core::fmt::Write;
use heapless::{String, Vec};

pub struct SetGreetingText<'a> {
    pub text: &'a str,
}

pub struct GetGreetingText;

pub struct NoResponse;

impl AtatResp for NoResponse {};

pub struct GreetingText {
    pub text: String<64>,
};

impl AtatResp for GreetingText {};

impl<'a> AtatCmd for SetGreetingText<'a> {
    type Response = NoResponse;
    const MAX_LEN: usize = 64;

    fn write(&self, mut buf: &mut [u8]) -> usize {
        let buf_len = buf.len();
        use embedded_io::Write;
        write!(buf, "AT+CSGT={}", self.text);
        buf_len - buf.len()
    }

    fn parse(&self, resp: Result<&[u8], InternalError>) -> Result<Self::Response, Error> {
        Ok(NoResponse)
    }
}

impl AtatCmd for GetGreetingText {
    type Response = GreetingText;
    const MAX_LEN: usize = 8;

    fn write(&self, mut buf: &mut [u8]) -> usize {
        let cmd = b"AT+CSGT?";
        let len = cmd.len();
        buf[..len].copy_from_slice(cmd);
        len
    }

    fn parse(&self, resp: Result<&[u8], InternalError>) -> Result<Self::Response, Error> {
        // Parse resp into `GreetingText`
        Ok(GreetingText {
            text: String::try_from(core::str::from_utf8(resp.unwrap()).unwrap()).unwrap(),
        })
    }
}

§Same example with atat_derive:

use atat::atat_derive::{AtatCmd, AtatResp};
use heapless::String;

#[derive(Clone, AtatCmd)]
#[at_cmd("+CSGT", NoResponse)]
pub struct SetGreetingText<'a> {
    #[at_arg(position = 0, len = 32)]
    pub text: &'a str,
}

#[derive(Clone, AtatCmd)]
#[at_cmd("+CSGT?", GreetingText)]
pub struct GetGreetingText;

#[derive(Clone, AtatResp)]
pub struct NoResponse;

#[derive(Clone, AtatResp)]
pub struct GreetingText {
    #[at_arg(position = 0)]
    pub text: String<64>,
};

§Basic usage example (More available in examples folder):

ⓘ

use cortex_m::asm;
use hal::{
    gpio::{
        gpioa::{PA2, PA3},
        Alternate, Floating, Input, AF7,
    },
    pac::{interrupt, Peripherals, USART2},
    prelude::*,
    serial::{Config, Event::Rxne, Rx, Serial},
    timer::{Event, Timer},
};

use atat::{atat_derive::{AtatResp, AtatCmd}};

use heapless::{spsc::Queue, String};

use crate::rt::entry;
static mut INGRESS: Option<atat::IngressManager> = None;
static mut RX: Option<Rx<USART2>> = None;


#[derive(Clone, AtatResp)]
pub struct NoResponse;

#[derive(Clone, AtatCmd)]
#[at_cmd("", NoResponse, timeout_ms = 1000)]
pub struct AT;

#[entry]
fn main() -> ! {
    let p = Peripherals::take().unwrap();

    let mut flash = p.FLASH.constrain();
    let mut rcc = p.RCC.constrain();
    let mut pwr = p.PWR.constrain(&mut rcc.apb1r1);

    let mut gpioa = p.GPIOA.split(&mut rcc.ahb2);

    let clocks = rcc.cfgr.freeze(&mut flash.acr, &mut pwr);

    let tx = gpioa.pa2.into_af7(&mut gpioa.moder, &mut gpioa.afrl);
    let rx = gpioa.pa3.into_af7(&mut gpioa.moder, &mut gpioa.afrl);

    let mut timer = Timer::tim7(p.TIM7, 1.hz(), clocks, &mut rcc.apb1r1);
    let at_timer = Timer::tim6(p.TIM6, 100.hz(), clocks, &mut rcc.apb1r1);

    let mut serial = Serial::usart2(
        p.USART2,
        (tx, rx),
        Config::default().baudrate(115_200.bps()),
        clocks,
        &mut rcc.apb1r1,
    );

    serial.listen(Rxne);

    static mut RES_QUEUE: ResQueue<256> = Queue::new();
    static mut URC_QUEUE: UrcQueue<256, 10> = Queue::new();
    static mut COM_QUEUE: ComQueue = Queue::new();

    let queues = Queues {
        res_queue: unsafe { RES_QUEUE.split() },
        urc_queue: unsafe { URC_QUEUE.split() },
        com_queue: unsafe { COM_QUEUE.split() },
    };

    let (tx, rx) = serial.split();
    let (mut client, ingress) =
        ClientBuilder::new(tx, timer, atat::Config::new(atat::Mode::Timeout)).build(queues);

    unsafe { INGRESS = Some(ingress) };
    unsafe { RX = Some(rx) };

    // configure NVIC interrupts
    unsafe { cortex_m::peripheral::NVIC::unmask(hal::stm32::Interrupt::TIM7) };
    timer.listen(Event::TimeOut);

    // if all goes well you should reach this breakpoint
    asm::bkpt();

    loop {
        asm::wfi();

        match client.send(&AT) {
            Ok(response) => {
                // Do something with response here
            }
            Err(e) => {}
        }
    }
}

#[interrupt]
fn TIM7() {
    let ingress = unsafe { INGRESS.as_mut().unwrap() };
    ingress.digest();
}

#[interrupt]
fn USART2() {
    let ingress = unsafe { INGRESS.as_mut().unwrap() };
    let rx = unsafe { RX.as_mut().unwrap() };
    if let Ok(d) = nb::block!(rx.read()) {
        ingress.write(&[d]);
    }
}

§Optional Cargo Features

  • derive (enabled by default) - Re-exports atat_derive to allow deriving Atat__ traits.

Re-exports§

Modules§

Structs§

  • Config
    Configuration of both the ingress manager, and the AT client. Some of these parameters can be changed on the fly, through issuing a Command from the client.
  • Ingress

Enums§

  • CmeError
    Enumeration of Mobile Equipment errors, as defined in 3GPP TS 27.007 v17.1.0, section 9.2 (Mobile termination error result code +CME ERROR).
  • CmsError
    Enumeration of message errors, as defined in 3GPP TS 27.005 version 10 section 3.2.5.
  • ConnectionError
  • Error
    Errors returned by the crate
  • IngressError
  • InternalError
    Errors returned used internally within the crate
  • Response

Traits§