bare9 first trye

examples/bare9.rs

@@ -30,3 +30,109 @@
 //
 // https://play.rust-lang.org/,
 // offers a good way to prototype and share code snippets
+//
+// //! Output a PWM on pin PA0 and control its duty cycle via a serial interface
+//!
+//! - '*' increase duty by a factor of 2
+//! - '+' increase duty by 1
+//! - '-' decrease duty by 1
+//! - '/' decrease duty by a factor of 2
+#![deny(unsafe_code)]
+//#![deny(warnings)]
+#![feature(proc_macro)]
+#![no_std]
+
+extern crate cortex_m_rtfm as rtfm;
+extern crate f4;
+#[macro_use]
+extern crate cortex_m_debug;
+
+use core::u32;
+
+use f4::prelude::*;
+use f4::time::Hertz;
+use f4::{Channel, Pwm, Serial};
+use f4::serial::Event;
+use rtfm::{app, Threshold};
+
+const BAUD_RATE: Hertz = Hertz(115_200);
+const FREQUENCY: Hertz = Hertz(1_000);
+
+app! {
+    device: f4::stm32f40x,
+
+    tasks: {
+        USART2: {
+            path: rx,
+            resources: [TIM4, USART2],
+        },
+    },
+}
+
+fn init(p: init::Peripherals) {
+    ipln!("init");
+    let pwm = Pwm(p.TIM4);
+    let serial = Serial(p.USART2);
+
+    serial.init(BAUD_RATE.invert(), None, p.GPIOA, p.RCC);
+    serial.listen(Event::Rxne);
+
+    pwm.init(
+        FREQUENCY.invert(),
+        Channel::_1,
+        None,
+        p.GPIOA,
+        p.GPIOB,
+        p.GPIOC,
+        p.RCC,
+    );
+    pwm.set_duty(Channel::_1, 1000);
+
+    pwm.enable(Channel::_1);
+}
+
+fn idle() -> ! {
+    ipln!("idle");
+    loop {
+        rtfm::wfi();
+    }
+}
+
+fn rx(_t: &mut Threshold, r: USART2::Resources) {
+    let pwm = Pwm(&**r.TIM4);
+    let serial = Serial(&**r.USART2);
+
+    //let byte: u8 = '+'.unwerp();
+    let byte = serial.read().unwrap();
+    // Echo back to signal we are alive
+   // serial.write(byte).unwrap();
+    
+    ipln!("resewed {:?}", byte);
+
+    match byte {
+        b'+' | b'-' | b'*' | b'/' => {
+            let duty = pwm.get_duty(Channel::_1);
+
+            match byte {
+                b'+' => {
+                    let max = pwm.get_max_duty();
+                    pwm.set_duty(Channel::_1, if duty < max { duty + 1 } else { max });
+                }
+                b'-' => {
+                    pwm.set_duty(Channel::_1, duty.checked_sub(1).unwrap_or(0));
+                }
+                b'*' => {
+                    let new_duty = duty.checked_mul(2).unwrap_or(u32::MAX);
+                    let max_duty = pwm.get_max_duty();
+
+                    if new_duty < max_duty {
+                        pwm.set_duty(Channel::_1, new_duty)
+                    }
+                }
+                b'/' => pwm.set_duty(Channel::_1, duty / 2),
+                _ => ipln!("iner error"),//{ /* unreachable */ }
+            }
+        }
+        _ => ipln!("outher error"),//{}
+    }
+}