added sine mode

pwm_dac_saw_sampling/Cargo.toml

@@ -83,3 +83,7 @@ debug-assertions = false
 incremental = false
 lto = 'fat'
 opt-level = 3
+
+[dependencies.num-traits]
+version = "0.2.14"
+default-features = false

pwm_dac_saw_sampling/src/example_1000hz_sine.rs

@@ -0,0 +1,119 @@
+#![no_std]
+#![no_main]
+
+use cortex_m_rt::entry;
+use defmt::*;
+use defmt_rtt as _;
+use embedded_hal::timer::CountDown;
+use embedded_hal::PwmPin;
+use embedded_time::duration::*;
+use panic_probe as _;
+use rp2040_hal as hal;
+
+use hal::{
+    clocks::{init_clocks_and_plls},
+    pac,
+    sio::Sio,
+    watchdog::Watchdog,
+};
+
+#[link_section = ".boot2"]
+#[used]
+pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER_W25Q080;
+
+#[entry]
+fn main() -> ! {
+    info!("Program start");
+    let mut pac      = pac::Peripherals::take().unwrap();
+    let _core         = pac::CorePeripherals::take().unwrap();
+    let mut watchdog = Watchdog::new(pac.WATCHDOG);
+    let sio          = Sio::new(pac.SIO);
+
+    // External high-speed crystal on the pico board is 12Mhz
+    let external_xtal_freq_hz = 12_000_000u32;
+    let _clocks =
+        init_clocks_and_plls(
+            external_xtal_freq_hz,
+            pac.XOSC,
+            pac.CLOCKS,
+            pac.PLL_SYS,
+            pac.PLL_USB,
+            &mut pac.RESETS,
+            &mut watchdog)
+        .ok()
+        .unwrap();
+
+    let timer = hal::timer::Timer::new(pac.TIMER, &mut pac.RESETS);
+    let mut cnt_down = timer.count_down();
+
+    let mut pwm_slices = hal::pwm::Slices::new(pac.PWM, &mut pac.RESETS);
+
+    let pwm = &mut pwm_slices.pwm7;
+    pwm.enable();
+    pwm.set_div_int(1);
+    pwm.set_div_frac(0);
+
+    let pins =
+        hal::gpio::Pins::new(
+            pac.IO_BANK0, pac.PADS_BANK0, sio.gpio_bank0, &mut pac.RESETS);
+
+    let top = 255; // changing this changes the PWM frequency!
+    pwm.set_top(top);
+
+    let channel = &mut pwm.channel_b;
+    channel.output_to(pins.gpio15);
+
+    let sin =
+        unsafe {
+            core::mem::transmute::<_, fn(f32) -> f32>
+                (rp2040_hal::rom_data::float_funcs::fsin())
+        };
+
+    let mut phase = 0.0;
+    loop {
+        cnt_down.start((25_u32).microseconds());
+
+        let y = (sin(phase * 3.141 * 2.0) + 1.0) * 0.5;
+
+        channel.set_duty((y * (top + 1) as f32) as u16);
+
+        phase = phase + (440.0 / 40000.0);
+        while phase > 1.0 { phase -= 1.0; }
+
+        let _ = nb::block!(cnt_down.wait());
+    }
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+//    let mut delay =
+//        cortex_m::delay::Delay::new(
+//            core.SYST,
+//            clocks.system_clock.freq().integer());
+
+
+//    let mut led_pin = pins.gpio25.into_push_pull_output();
+//        info!("on!");
+//        led_pin.set_high().unwrap();
+//        info!("off!");
+//        led_pin.set_low().unwrap();
+
+//        duty = (duty + 1) % (steps + 1);
+//        channel.set_duty(duty * tPs);
+//        let h = rp2040_hal::rom_data::float_funcs::fsin(
+//            phase * 3.14159265359 * 2.0);

pwm_dac_saw_sampling/src/main.rs

@@ -57,19 +57,36 @@ fn main() -> ! {
         hal::gpio::Pins::new(
             pac.IO_BANK0, pac.PADS_BANK0, sio.gpio_bank0, &mut pac.RESETS);
 
-    let top = 200; // changing this changes the PWM frequency!
+    let top = 255; // changing this changes the PWM frequency!
     pwm.set_top(top);
 
     let channel = &mut pwm.channel_b;
     channel.output_to(pins.gpio15);
 
+    let saw_mode = false;
+
+    use num_traits::float::FloatCore;
+
+    let sin =
+        unsafe {
+            core::mem::transmute::<_, fn(f32) -> f32>
+                (rp2040_hal::rom_data::float_funcs::fsin())
+        };
+
     let mut phase = 0.0;
     loop {
         cnt_down.start((25_u32).microseconds());
 
-        channel.set_duty((phase * top as f32) as u16);
+        let y =
+            if saw_mode {
+                phase
+            } else {
+                (sin(phase * 3.141 * 2.0) + 1.0) * 0.5
+            };
+
+        channel.set_duty((y * (top + 1) as f32).floor() as u16);
 
-        phase = phase + (1000.0 / 40000.0);
+        phase = phase + (440.0 / 40000.0);
         while phase > 1.0 { phase -= 1.0; }
 
         let _ = nb::block!(cnt_down.wait());