Bring over DAC example (relies upon stm32-data update)

examples/stm32h7/src/bin/dac.rs

@@ -0,0 +1,92 @@
+#![no_std]
+#![no_main]
+#![feature(trait_alias)]
+#![feature(min_type_alias_impl_trait)]
+#![feature(impl_trait_in_bindings)]
+#![feature(type_alias_impl_trait)]
+
+#[path = "../example_common.rs"]
+mod example_common;
+
+use embassy_stm32::gpio::{Level, Output, Input, Pull, NoPin};
+use embedded_hal::digital::v2::{OutputPin, InputPin};
+use example_common::*;
+
+use cortex_m_rt::entry;
+use stm32h7::stm32h743 as pac;
+use embassy_stm32::spi::{Spi, MODE_0, ByteOrder, Config};
+use embassy_stm32::time::Hertz;
+use embedded_hal::blocking::spi::Transfer;
+use stm32h7xx_hal::{rcc, prelude::*};
+use embassy_stm32::dac::{Dac, Value, Channel};
+
+#[entry]
+fn main() -> ! {
+    info!("Hello World, dude!");
+
+    let pp = pac::Peripherals::take().unwrap();
+
+    let pwrcfg = pp.PWR.constrain()
+        .freeze();
+
+    let rcc = pp.RCC.constrain();
+
+    let ccdr = rcc
+        .sys_ck(96.mhz())
+        .pclk1(48.mhz())
+        .pclk2(48.mhz())
+        .pclk3(48.mhz())
+        .pclk4(48.mhz())
+        .pll1_q_ck(48.mhz())
+        .freeze(pwrcfg, &pp.SYSCFG);
+
+    let pp = unsafe { pac::Peripherals::steal() };
+
+    pp.DBGMCU.cr.modify(|_, w| {
+        w.dbgsleep_d1().set_bit();
+        w.dbgstby_d1().set_bit();
+        w.dbgstop_d1().set_bit();
+        w.d1dbgcken().set_bit();
+        w
+    });
+
+    pp.RCC.apb1lenr.modify(|_, w|{
+        w.dac12en().set_bit();
+        w
+    });
+
+    pp.RCC.ahb4enr.modify(|_, w| {
+        w.gpioaen().set_bit();
+        w.gpioben().set_bit();
+        w.gpiocen().set_bit();
+        w.gpioden().set_bit();
+        w.gpioeen().set_bit();
+        w.gpiofen().set_bit();
+        w
+    });
+
+    let p = embassy_stm32::init(Default::default());
+
+    let mut dac = Dac::new(p.DAC1, p.PA4, NoPin);
+
+    loop {
+        for v in 0..=255 {
+            dac.set(Channel::Ch1, Value::Bit8(to_sine_wave(v)));
+            dac.trigger( Channel::Ch1 );
+        }
+    }
+}
+
+use micromath::F32Ext;
+
+fn to_sine_wave(v: u8) -> u8 {
+    if v >= 128 {
+        // top half
+        let r = 3.14 * ( (v-128) as f32/ 128.0) ;
+        (r.sin() * 128.0 + 127.0) as u8
+    } else {
+        // bottom half
+        let r = 3.14 + 3.14 * (v as f32/ 128.0);
+        (r.sin() * 128.0 + 127.0) as u8
+    }
+}