Switch back to MonoTimer from HAL

This switches back from the local replacement for MonoTimer from 814c051
to the one re-added with HAL release 0.8.0. MonoTimers interface
changed in the meantime so this commit takes this into account as well.

Author: sirhcel

src/11-usart/auxiliary/src/lib.rs

@@ -9,17 +9,15 @@ pub use cortex_m::{asm::bkpt, iprint, iprintln, peripheral::ITM};
 pub use cortex_m_rt::entry;
 pub use stm32f3_discovery::stm32f3xx_hal::pac::usart1;
 
-pub mod monotimer;
-
 use stm32f3_discovery::stm32f3xx_hal::{
     prelude::*,
     serial::Serial,
     pac::{self, USART1},
+    timer::MonoTimer,
 };
-use monotimer::MonoTimer;
 
 pub fn init() -> (&'static mut usart1::RegisterBlock, MonoTimer, ITM) {
-    let cp = cortex_m::Peripherals::take().unwrap();
+    let mut cp = cortex_m::Peripherals::take().unwrap();
     let dp = pac::Peripherals::take().unwrap();
 
     let mut flash = dp.FLASH.constrain();
@@ -56,7 +54,7 @@ pub fn init() -> (&'static mut usart1::RegisterBlock, MonoTimer, ITM) {
     unsafe {
         (
             &mut *(USART1::ptr() as *mut _),
-            MonoTimer::new(cp.DWT, clocks),
+            MonoTimer::new(cp.DWT, clocks, &mut cp.DCB),
             cp.ITM,
         )
     }