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#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]
use defmt::info;
use embassy_executor::Spawner;
use embassy_nrf::saadc::{CallbackResult, ChannelConfig, Config, Saadc};
use embassy_nrf::timer::Frequency;
use embassy_nrf::{bind_interrupts, saadc};
use embassy_time::Duration;
use {defmt_rtt as _, panic_probe as _};
// Demonstrates both continuous sampling and scanning multiple channels driven by a PPI linked timer
bind_interrupts!(struct Irqs {
SAADC => saadc::InterruptHandler;
});
#[embassy_executor::main]
async fn main(_p: Spawner) {
let mut p = embassy_nrf::init(Default::default());
let config = Config::default();
let channel_1_config = ChannelConfig::single_ended(&mut p.P0_02);
let channel_2_config = ChannelConfig::single_ended(&mut p.P0_03);
let channel_3_config = ChannelConfig::single_ended(&mut p.P0_04);
let mut saadc = Saadc::new(
p.SAADC,
Irqs,
config,
[channel_1_config, channel_2_config, channel_3_config],
);
// This delay demonstrates that starting the timer prior to running
// the task sampler is benign given the calibration that follows.
embassy_time::Timer::after(Duration::from_millis(500)).await;
saadc.calibrate().await;
let mut bufs = [[[0; 3]; 500]; 2];
let mut c = 0;
let mut a: i32 = 0;
saadc
.run_task_sampler(
&mut p.TIMER0,
&mut p.PPI_CH0,
&mut p.PPI_CH1,
Frequency::F1MHz,
1000, // We want to sample at 1KHz
&mut bufs,
move |buf| {
// NOTE: It is important that the time spent within this callback
// does not exceed the time taken to acquire the 1500 samples we
// have in this example, which would be 10us + 2us per
// sample * 1500 = 18ms. You need to measure the time taken here
// and set the sample buffer size accordingly. Exceeding this
// time can lead to the peripheral re-writing the other buffer.
for b in buf {
a += b[0] as i32;
}
c += buf.len();
if c > 1000 {
a = a / c as i32;
info!("channel 1: {=i32}", a);
c = 0;
a = 0;
}
CallbackResult::Continue
},
)
.await;
}
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