From 1416261c03745d94b375442d3fdda5eca9ae6078 Mon Sep 17 00:00:00 2001
From: Josef Utbult <josutb-7@student.ltu.se>
Date: Fri, 5 Mar 2021 16:42:09 +0100
Subject: [PATCH] bare5_2
---
examples/rtic_bare5.rs | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/examples/rtic_bare5.rs b/examples/rtic_bare5.rs
index c92497c..926d3d3 100644
--- a/examples/rtic_bare5.rs
+++ b/examples/rtic_bare5.rs
@@ -25,6 +25,7 @@ mod stm32f40x {
pub const GPIOA_BASE: u32 = AHB1PERIPH_BASE + 0x0000;
}
use address::*;
+ use cortex_m_semihosting::hprint;
pub struct VolatileCell<T> {
pub value: cell::UnsafeCell<T>,
@@ -58,7 +59,19 @@ mod stm32f40x {
impl VolatileCell<u32> {
#[inline(always)]
pub fn modify(&self, offset: u8, width: u8, value: u32) {
- // your code here
+
+ let cell_val = VolatileCell::read(&self);
+ let mut mask = 0;
+
+ for i in 0..width {
+ mask |= 1 << i;
+ }
+
+ let masked_value = value & mask;
+
+ let return_val = (cell_val & !(mask << offset)) | masked_value << offset;
+ VolatileCell::write(&self, return_val)
+
}
}
@@ -177,7 +190,7 @@ const APP: () = {
let r = gpioa.MODER.read() & !(0b11 << (5 * 2)); // read and mask
gpioa.MODER.write(r | 0b01 << (5 * 2)); // set output mode
- // test_modify();
+ test_modify();
loop {
// set PA5 high
@@ -243,6 +256,6 @@ const APP: () = {
// What if we could automatically generate that from Vendors specifications (SVD files)?
// Wouldn't that be great?
//
-// ** your answer here **
+// Sure, I guess...
//
// Commit your answers (bare5_2)
--
GitLab