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<64> for SetGreetingText<'a> {
type Response = NoResponse;

fn as_bytes(&self) -> Vec<u8, 64> {
let mut buf: Vec<u8, 64> = Vec::new();
write!(buf, "AT+CSGT={}", self.text);
buf
}

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

impl AtatCmd<8> for GetGreetingText {
type Response = GreetingText;

fn as_bytes(&self) -> Vec<u8, 8> {
Vec::from_slice(b"AT+CSGT?").unwrap()
}

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