1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
#![no_std]
#![no_main]
use core::fmt::Write;
use core::str::from_utf8;
use cortex_m_rt::entry;
use defmt::*;
use embassy_executor::Executor;
use embassy_stm32::mode::Async;
use embassy_stm32::time::mhz;
use embassy_stm32::{Config, spi};
use heapless::String;
use static_cell::StaticCell;
use {defmt_rtt as _, panic_probe as _};
#[embassy_executor::task]
async fn main_task(mut spi: spi::Spi<'static, Async, spi::mode::Master>) {
for n in 0u32.. {
let mut write: String<128> = String::new();
let mut read = [0; 128];
core::write!(&mut write, "Hello DMA World {}!\r\n", n).unwrap();
// transfer will slice the &mut read down to &write's actual length.
spi.transfer(&mut read, write.as_bytes()).await.ok();
info!("read via spi+dma: {}", from_utf8(&read).unwrap());
}
}
static EXECUTOR: StaticCell<Executor> = StaticCell::new();
#[entry]
fn main() -> ! {
info!("Hello World!");
let mut config = Config::default();
{
use embassy_stm32::rcc::*;
config.rcc.hsi = Some(HSIPrescaler::DIV1);
config.rcc.csi = true;
config.rcc.pll1 = Some(Pll {
source: PllSource::HSI,
prediv: PllPreDiv::DIV4,
mul: PllMul::MUL50,
divp: Some(PllDiv::DIV2),
divq: Some(PllDiv::DIV8), // used by SPI3. 100Mhz.
divr: None,
});
config.rcc.sys = Sysclk::PLL1_P; // 400 Mhz
config.rcc.ahb_pre = AHBPrescaler::DIV2; // 200 Mhz
config.rcc.apb1_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb2_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb3_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.apb4_pre = APBPrescaler::DIV2; // 100 Mhz
config.rcc.voltage_scale = VoltageScale::Scale1;
}
let p = embassy_stm32::init(config);
let mut spi_config = spi::Config::default();
spi_config.frequency = mhz(1);
let spi = spi::Spi::new(p.SPI3, p.PB3, p.PB5, p.PB4, p.DMA1_CH3, p.DMA1_CH4, spi_config);
let executor = EXECUTOR.init(Executor::new());
executor.run(|spawner| {
spawner.spawn(unwrap!(main_task(spi)));
})
}
|
