.vscode/launch.json

@@ -4,6 +4,7 @@
     // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
     "version": "0.2.0",
     "configurations": [
+
         // Launch configuration for `app`
         // - debug
         // - semihosting
@@ -16,8 +17,28 @@
             "preLaunchTask": "cargo build",
             "executable": "./target/thumbv7em-none-eabihf/debug/app",
             "configFiles": [
-                "interface/stlink.cfg",
-                // "interface/stlink-v2-1.cfg",  // deprecated setup script
+                "interface/stlink-v2-1.cfg",
+                "target/stm32f4x.cfg"
+            ],
+            "postLaunchCommands": [
+                "monitor arm semihosting enable"
+            ],
+            "runToMain": true,
+            "cwd": "${workspaceRoot}"
+        },
+         // Launch configuration for `app`
+        // - debug
+        // - semihosting
+        // - run to main
+        {
+            "type": "cortex-debug",
+            "request": "launch",
+            "servertype": "openocd",
+            "name": "examples (debug)",
+            "preLaunchTask": "cargo build --examples",
+            "executable": "./target/thumbv7em-none-eabihf/debug/examples/${fileBasenameNoExtension}",
+            "configFiles": [
+                "interface/stlink-v2-1.cfg",
                 "target/stm32f4x.cfg"
             ],
             "postLaunchCommands": [
@@ -39,8 +60,7 @@
             "preLaunchTask": "cargo build --example",
             "executable": "./target/thumbv7em-none-eabihf/debug/examples/${fileBasenameNoExtension}",
             "configFiles": [
-                "interface/stlink.cfg",
-                // "interface/stlink-v2-1.cfg", // deprecated setup script
+                "interface/stlink-v2-1.cfg",
                 "target/stm32f4x.cfg"
             ],
             "postLaunchCommands": [
@@ -75,8 +95,7 @@
             "preLaunchTask": "cargo build --example",
             "executable": "./target/thumbv7em-none-eabihf/debug/examples/${fileBasenameNoExtension}",
             "configFiles": [
-                "interface/stlink.cfg",
-                // "interface/stlink-v2-1.cfg", // deprecated setup script
+                "interface/stlink-v2-1.cfg",
                 "target/stm32f4x.cfg"
             ],
             "postLaunchCommands": [
@@ -150,8 +169,7 @@
             "preLaunchTask": "cargo build --example --release",
             "executable": "./target/thumbv7em-none-eabihf/release/examples/${fileBasenameNoExtension}",
             "configFiles": [
-                "interface/stlink.cfg",
-                // "interface/stlink-v2-1.cfg", // deprecated setup script
+                "interface/stlink-v2-1.cfg",
                 "target/stm32f4x.cfg"
             ],
             "postLaunchCommands": [
@@ -175,8 +193,7 @@
             "preLaunchTask": "cargo build --example --release --features stm32f4",
             "executable": "./target/thumbv7em-none-eabihf/release/examples/${fileBasenameNoExtension}",
             "configFiles": [
-                "interface/stlink.cfg",
-                // "interface/stlink-v2-1.cfg", // deprecated setup script
+                "interface/stlink-v2-1.cfg",
                 "target/stm32f4x.cfg"
             ],
             "postLaunchCommands": [

examples/bare0.rs

@@ -22,25 +22,49 @@ use panic_semihosting as _;
 use cortex_m_rt::entry;
 
 // a constant (cannot be changed at run-time)
-const X_INIT: u32 = 10;
-// const X_INIT: u32 = core::u32::MAX;
+const X_INIT: u32 = core::u32::MAX;
 
 // global mutable variables (changed using unsafe code)
 static mut X: u32 = X_INIT;
 static mut Y: u32 = 0;
 
+fn write_x(x: u32, i: u32) {
+    unsafe{
+        X = x.wrapping_add(i);
+    }
+}
+
+fn write_y(y: u32) {
+    unsafe{
+        Y = y;
+    }
+}
+
+
+fn read_y() -> u32 {
+    unsafe{
+        Y
+    }
+}
+
+fn read_x() -> u32 {
+    unsafe{
+        X
+    }
+}
+
 #[entry]
 fn main() -> ! {
     // local mutable variable (changed in safe code)
-    let mut x = unsafe { X };
+    let mut x = read_x();
 
     loop {
-        x += 1; // <- place breakpoint here (3)
-        unsafe {
-            X += 1;
-            Y = X;
-            assert!(x == X && X == Y);
-        }
+        x = x.wrapping_add(1); // <- place breakpoint here (3)
+
+        write_x(read_x(), 1);
+        write_y(read_x());
+        assert!(x == read_x() && read_x() == read_y());
+
     }
 }
 
@@ -56,12 +80,14 @@ fn main() -> ! {
 //
 //    Look under Variables/Local what do you find.
 //
-//    ** your answer here **
+//    x: 9389056
 //
 //    In the Expressions (WATCH -vscode) view add X and Y
 //    what do you find
 //
 //    ** your answer here **
+//    X: 9389055
+//    Y: <optimized out>
 //
 //    Step through one complete iteration of the loop
 //    and see how the (Local) Variables are updated
@@ -69,6 +95,10 @@ fn main() -> ! {
 //
 // 	  ** place your answer here **
 //      
+//    x will update to 9389057
+//    eventually x will overflow and if rust runs in debug mode then rust will panic and 
+//    if it runs in release mode rust wont check for the overflow and just do a wrap the value
+//
 //    Commit your answers (bare0_1)
 //
 // 2. Alter the constant X_INIT so that `x += 1` directly causes `x` to wrap.
@@ -76,6 +106,8 @@ fn main() -> ! {
 //    (Hint, look under OUTPUT/Adopter Output to see the `openocd` output.)
 //
 //    ** your answer here **
+//    The program panics
+//    panicked at 'attempt to add with overflow', examples/bare0.rs:42:9
 //
 //    Commit your answers (bare0_2)
 //
@@ -84,10 +116,12 @@ fn main() -> ! {
 //    Change (both) += operations to use wrapping_add
 //    load and run the program, what happens
 //    ** your answer here **
-//
+//    x wrapps around and become 0
+//    X does nothing 
 //    Now continue execution, what happens
 //    ** your answer here **
-//
+//    x continues to add up
+//    X still does nothing
 //    Commit your answers (bare0_3)
 //
 //    (If the program did not succeed back to the breakpoint
@@ -96,6 +130,8 @@ fn main() -> ! {
 // 4. Change the assertion to `assert!(x == X && X == Y + 1)`, what happens?
 //
 //    ** place your answer here **
+//    panic because the assertion fails
+//    panicked at 'assertion failed: x == X && X == Y + 1', examples/bare0.rs:46:13
 //     
 //    Commit your answers (bare0_4)
 //

examples/bare1.rs

@@ -59,10 +59,16 @@ fn main() -> ! {
 //    (passing 3 breakpoints)
 //
 //    ** your answer here **
+//    The program hits the first breakpoint again with a callstack
+//    with a lot of elements in the callstack pointing to 0x08000424
+//    local x variable contains various values
 //
 //    What is the `ITM` output.
 //
-//    ** your answer here **
+// Program
+//  received signal SIGTRAP, Trace/breakpoint trap.
+// bare1::__cortex_m_rt_main () at examples/bare1.rs:22
+// 22	        cortex_m::asm::bkpt();
 //
 //    Commit your answer (bare1_1)
 //
@@ -74,16 +80,42 @@ fn main() -> ! {
 //    What is the output of:
 //    > disassemble
 //
-//    ** your answer here **
+//    Please check OUTPUT tab (Adapter Output) for output from openocd
+
+
+// disassemble
+// Dump of assembler code for function bare1::__cortex_m_rt_main:
+//    0x0800040a <+0>:	sub	sp, #8
+//    0x0800040c <+2>:	mvn.w	r0, #1
+//    0x08000410 <+6>:	str	r0, [sp, #4]
+//    0x08000412 <+8>:	bkpt	0x0000
+//    0x08000414 <+10>:	mov.w	r0, #4294967295	; 0xffffffff
+//    0x08000418 <+14>:	add	r4, sp, #4
+//    0x0800041a <+16>:	str	r0, [sp, #4]
+//    0x0800041c <+18>:	bkpt	0x0000
+//    0x0800041e <+20>:	mov	r0, r4
+//    0x08000420 <+22>:	bl	0x8000400 <core::ptr::read_volatile>
+// => 0x08000424 <+26>:	bkpt	0x0000
+//    0x08000426 <+28>:	ldr	r0, [sp, #4]
+//    0x08000428 <+30>:	adds	r0, #1
+//    0x0800042a <+32>:	bcc.n	0x800041a <bare1::__cortex_m_rt_main+16>
+//    0x0800042c <+34>:	movw	r0, #5984	; 0x1760
+//    0x08000430 <+38>:	movt	r0, #2048	; 0x800
+//    0x08000434 <+42>:	movw	r2, #5956	; 0x1744
+//    0x08000438 <+46>:	movt	r2, #2048	; 0x800
+//    0x0800043c <+50>:	movs	r1, #28
+//    0x0800043e <+52>:	bl	0x800053a <core::panicking::panic>
+//    0x08000442 <+56>:	udf	#254	; 0xfe
+// End of assembler dump.
 //
 //    How many instructions are in between the two `bkpt` instructions in the loop.
 //    Notice, the generated code may not be exactly what you expect :)
 //
-//    ** your answer here **
+//    THere are 6 instrucations inbetween
 //
 //    Which instruction stores the local variable on the stack.
 //
-//    ** your answer here **
+//    0x0800041a <+16>:	str	r0, [sp, #4]
 //
 //    Commit your answers (bare1_2)
 //
@@ -99,15 +131,25 @@ fn main() -> ! {
 //    What is the output of:
 //    > disassemble
 //
-//    ** your answer here **
+//      Dump of assembler code for function bare1::__cortex_m_rt_main:
+//      0x08000406 <+0>:	sub	sp, #4
+//      0x08000408 <+2>:	mvn.w	r0, #1
+//      0x0800040c <+6>:	str	r0, [sp, #0]
+//      0x0800040e <+8>:	adds	r0, #1
+//      0x08000410 <+10>:	bkpt	0x0000
+//      0x08000412 <+12>:	str	r0, [sp, #0]
+//      => 0x08000414 <+14>:	bkpt	0x0000
+//      0x08000416 <+16>:	ldr	r0, [sp, #0]
+//      0x08000418 <+18>:	b.n	0x800040e <bare1::__cortex_m_rt_main+8>
+//      End of assembler dump.
 //
 //    How many instructions are in between the two `bkpt` instructions.
 //
-//    ** your answer here **
+//    1
 //
 //    Where is the local variable stored?
 //
-//    ** your answer here **
+//    0x08000412 <+12>:	str	r0, [sp, #0]
 //
 //    Is there now any reference to the panic handler?
 //    If not, why is that the case?
@@ -172,9 +214,21 @@ fn main() -> ! {
 //
 //    What is now the disassembly of the loop (in debug/dev mode):
 //
-//    ** your answer here **
-//
-//    commit your answers (bare1_5)
+//         Dump of assembler code for function bare1::__cortex_m_rt_main:
+//         0x0800040a <+0>:	sub	sp, #8
+//         0x0800040c <+2>:	mvn.w	r0, #1
+//         0x08000410 <+6>:	str	r0, [sp, #4]
+//         0x08000412 <+8>:	add	r4, sp, #4
+//         0x08000414 <+10>:	bkpt	0x0000
+//         0x08000416 <+12>:	ldr	r0, [sp, #4]
+//         0x08000418 <+14>:	adds	r0, #1
+//         0x0800041a <+16>:	str	r0, [sp, #4]
+//         => 0x0800041c <+18>:	bkpt	0x0000
+//         0x0800041e <+20>:	mov	r0, r4
+//         0x08000420 <+22>:	bl	0x8000400 <core::ptr::read_volatile>
+//         0x08000424 <+26>:	b.n	0x8000414 <bare1::__cortex_m_rt_main+10>
+//         End of assembler dump.
+//    commit your answers (bare1_4)
 //
 //    Now restore the `.cargo/config` to its original state.
 //

examples/bare2.rs

@@ -18,7 +18,7 @@ use panic_halt as _;
 use cortex_m::{iprintln, peripheral::DWT, Peripherals};
 use cortex_m_rt::entry;
 
-// burns CPU cycles by just looping `i` times
+// burns CPU cycles by just 5looping `i` times
 #[inline(never)]
 fn wait(i: u32) {
     for _ in 0..i {
@@ -77,18 +77,24 @@ fn main() -> ! {
 //
 //    What is the output in the ITM console?
 //
-//    ** your answer here **
+//      bare2
+//      Start 2012359631
+//      End 2139359709
+//      Diff 127000078
 //    
 //    Rebuild and run in release mode
 //
 //    > cargo build --example bare2 --release
 //
-//    ** your answer here **
+//    bare2
+    // Start 3019839635
+    // End 3026839650
+    // Diff 7000015
 //
 //    Compute the ratio between debug/release optimized code
 //    (the speedup).
 //
-//    ** your answer here **
+//    18,1428 times faster
 //
 //    commit your answers (bare2_1)
 //

openocd.cfg

-source [find interface/stlink.cfg]
-# deprecated
-# source [find interface/stlink-v2-1.cfg] 
+source [find interface/stlink-v2-1.cfg]
+
 transport select hla_swd
 
 # increase working area to 64KB