println and gpio

.vscode/tasks.json

@@ -25,16 +25,27 @@
             "command": "xargo build --example gpio",
             "problemMatcher": [
                 "$rustc"
-            ]
+            ],
+            "group": {
+                "kind": "build",
+                "isDefault": true
+            }
         },
         {
             "taskName": "xargo build --example usart1",
             "type": "shell",
             "command": "xargo build --example usart1",
-            "group": {
-                "kind": "build",
-                "isDefault": true
+            "problemMatcher": [
+                "$rustc"
+            ]
         },
+        {
+            "type": "shell",
+            "taskName": "cargo build",
+            "command": "cargo",
+            "args": [
+                "build"
+            ],
             "problemMatcher": [
                 "$rustc"
             ]

examples/gpio.rs

@@ -5,13 +5,11 @@
 #![no_std]
 
 extern crate cortex_m_rtfm as rtfm;
-extern crate cortex_m_semihosting as semihosting;
+#[macro_use]
 extern crate nucleo_64;
 extern crate stm32f40x;
 
 use rtfm::app;
-use semihosting::hio;
-use core::fmt::Write;
 use nucleo_64::gpio::PA5;
 
 app! {
@@ -19,7 +17,7 @@ app! {
 }
 
 fn init(p: init::Peripherals) {
-    writeln!(hio::hstdout().unwrap(), "Init!").unwrap();
+    println!("Init!");
     // RM0368 6.3.9
     // enable clock to GPIOA
     p.RCC.ahb1enr.modify(|_, w| w.gpioaen().enable());
@@ -33,12 +31,12 @@ fn init(p: init::Peripherals) {
 }
 
 fn idle() -> ! {
-    writeln!(hio::hstdout().unwrap(), "PA5 high!").unwrap();
+    loop {
+        println!("PA5 high!");
         PA5.high();
-    writeln!(hio::hstdout().unwrap(), "PA5 low!").unwrap();
+        rtfm::bkpt();
+        println!("PA5 low!");
         PA5.low();
-    // Sleep
-    loop {
-        rtfm::wfi();
+        rtfm::bkpt();
     }
 }

examples/usart1.rs

@@ -11,6 +11,7 @@
 
 extern crate cortex_m_rtfm as rtfm;
 extern crate cortex_m_semihosting as semihosting;
+#[macro_use]
 extern crate nb;
 extern crate nucleo_64;
 extern crate stm32f40x;
@@ -109,6 +110,15 @@ fn init(p: init::Peripherals) {
 
     // serial.init(BAUD_RATE.invert(), p.AFIO, None, p.GPIOA, p.RCC);
 
+    // echo incoming
+    loop {
+        let b = block!(read(p.USART2)).unwrap();
+        write(p.USART2, b).unwrap();
+    }
+
+
+
+
     const BYTE: u8 = b'A';
 
     assert!(write(p.USART2, BYTE).is_ok());
@@ -140,6 +150,7 @@ pub enum Error {
     Overrun,
     #[doc(hidden)] _Extensible,
 }
+
 fn write(usart2: &USART2, byte: u8) -> Result<()> {
     let sr = usart2.sr.read();
 

src/lib.rs

@@ -139,3 +139,15 @@ pub mod apb1 {
 pub mod apb2 {
     frequency!(16_000_000);
 }
+
+/// println over semihosting
+#[macro_export]
+macro_rules! println {
+    ($e:expr) => {
+        {  
+            extern crate cortex_m_semihosting;
+            use core::fmt::Write;            
+            writeln!(cortex_m_semihosting::hio::hstdout().unwrap(), $e).unwrap();
+        }
+    }
+}