From 71c9a66129f2cf925cb743470350d450442cb6e0 Mon Sep 17 00:00:00 2001
From: "henthe-5@student.ltu.se" <henthe-5@student.ltu.se>
Date: Fri, 22 Feb 2019 13:04:21 +0100
Subject: [PATCH] bare5_2
---
examples/bare5.rs | 84 +++++++++++++++++++++++------------------------
1 file changed, 41 insertions(+), 43 deletions(-)
diff --git a/examples/bare5.rs b/examples/bare5.rs
index be4f637..89215af 100644
--- a/examples/bare5.rs
+++ b/examples/bare5.rs
@@ -56,13 +56,17 @@ mod stm32f40x {
// offset (field offset)
// width (field width)
// value (new value that the field should take)
- //
- // impl VolatileCell<u32> {
- // #[inline(always)]
- // pub fn modify(&self, offset: u8, width: u8, value: u32) {
- // // your code here
- // }
- // }
+ impl VolatileCell<u32> {
+ #[inline(always)]
+ pub fn modify(&self, offset: u8, width: u8, value: u32) {
+ let current_value = self.read();
+ let b = 0b11111111;
+ let mask = !( (b << offset + width) | !(b << offset) );
+ let masked_value = mask & (value << offset);
+ let modified_value = (current_value & !mask) | masked_value;
+ self.write(modified_value);
+ }
+ }
#[repr(C)]
#[allow(non_snake_case)]
@@ -141,27 +145,27 @@ fn wait(i: u32) {
}
// simple test of Your `modify`
-//fn test() {
-// let t:VolatileCell<u32> = unsafe { core::mem::uninitialized() };
-// t.write(0);
-// assert!(t.read() == 0);
-// t.modify(3, 3, 0b10101);
-// //
-// // 10101
-// // ..0111000
-// // ---------
-// // 000101000
-// assert!(t.read() == 0b101 << 3);
-// t.modify(4, 3, 0b10001);
-// // 000101000
-// // 111
-// // 001
-// // 000011000
-// assert!(t.read() == 0b011 << 3);
-
-// if << is used, your code will panic in dev (debug), but not in release mode
-// t.modify(32, 3, 1);
-//}
+fn test() {
+ let t:VolatileCell<u32> = unsafe { core::mem::uninitialized() };
+ t.write(0);
+ assert!(t.read() == 0);
+ t.modify(3, 3, 0b10101);
+ //
+ // 10101
+ // ..0111000
+ // ---------
+ // 000101000
+ assert!(t.read() == 0b101 << 3);
+ t.modify(4, 3, 0b10001);
+ // 000101000
+ // 111
+ // 001
+ // 000011000
+ assert!(t.read() == 0b011 << 3);
+
+ //if << is used, your code will panic in dev (debug), but not in release mode
+ t.modify(32, 3, 1);
+}
// system startup, can be hidden from the user
#[entry]
@@ -169,7 +173,7 @@ fn main() -> ! {
let rcc = unsafe { &mut *RCC::get() }; // get the reference to RCC in memory
let gpioa = unsafe { &mut *GPIOA::get() }; // get the reference to GPIOA in memory
- // test(); // uncomment to run test
+ //test(); // uncomment to run test
idle(rcc, gpioa);
loop {}
}
@@ -177,24 +181,18 @@ fn main() -> ! {
// user application
fn idle(rcc: &mut RCC, gpioa: &mut GPIOA) {
// power on GPIOA
- let r = rcc.AHB1ENR.read(); // read
- rcc.AHB1ENR.write(r | 1 << (0)); // set enable
-
+ rcc.AHB1ENR.modify(0, 1, 0b1);
// configure PA5 as output
- let r = gpioa.MODER.read() & !(0b11 << (5 * 2)); // read and mask
- gpioa.MODER.write(r | 0b01 << (5 * 2)); // set output mode
-
+ gpioa.MODER.modify(5*2, 2, 0b01);
loop {
// set PA5 high
- // gpioa.BSRRH.write(1 << 5); // set bit, output hight (turn on led)
- gpioa.ODR.write(gpioa.ODR.read() | (1 << 5));
-
- wait(10_000);
+ gpioa.ODR.modify(5, 1, 0b1);
+ //Modify wait by the speedup of a release build.
+ wait(1_119_982);
// set PA5 low
- // gpioa.BSRRL.write(1 << 5); // clear bit, output low (turn off led)
- gpioa.ODR.write(gpioa.ODR.read() & !(1 << 5));
- wait(10_000);
+ gpioa.ODR.modify(5, 1, 0b0);
+ wait(1_119_982);
}
}
@@ -227,7 +225,7 @@ fn idle(rcc: &mut RCC, gpioa: &mut GPIOA) {
// - field width (in bits, u8),
// - and value (u32).
//
-// Implement and check that running `test` gives you expected behavior.
+// Implement and` gives you expected behavior.
//
// Change the code into using your new API.
//
--
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