Implement LED peripheral control

- Added init_led() to configure LED GPIO as output
- Added led_on(), led_off(), and toggle_led() functions
- Uses direct register access with volatile reads/writes
- Provides basic LED control for M2 Bootloader
- Ready for adaptation to specific MCU hardware

Author: m-a-h-b-u-b

app/src/peripherals.rs

@@ -1,11 +1,53 @@
-//! M2 Bootloader RUST 
-//! ------------------
+//! M2 Bootloader RUST App Peripherals Module
+//! -----------------------------------------
 //! License : Dual License
 //!           - Apache 2.0 for open-source / personal use
 //!           - Commercial license required for closed-source use
 //! Author  : Md Mahbubur Rahman
 //! URL     : <https://m-a-h-b-u-b.github.io>
-//! GitHub  : <https://github.com/m-a-h-b-u-b/M2-Bootloader-RUST>
+//! GitHub  : <https://github.com/m-a-h-b-u-b/M2-Bootloader-Rust>
 
-pub fn init_led() {}
-pub fn toggle_led() {}
+#![no_std]
+
+use core::ptr;
+
+const GPIO_PORT_BASE: u32 = 0x5000_0000; // Replace with your MCU GPIO base
+const LED_PIN: u32 = 5; // Example: Pin 5
+
+/// Initialize LED GPIO pin as output
+pub fn init_led() {
+    unsafe {
+        // Configure LED_PIN as output
+        let moder = (GPIO_PORT_BASE + 0x00) as *mut u32; // MODER register
+        let current = ptr::read_volatile(moder);
+        // Clear previous mode bits and set as output (01)
+        ptr::write_volatile(
+            moder,
+            (current & !(0b11 << (LED_PIN * 2))) | (0b01 << (LED_PIN * 2)),
+        );
+    }
+}
+
+/// Turn LED on
+pub fn led_on() {
+    unsafe {
+        let odr = (GPIO_PORT_BASE + 0x14) as *mut u32; // Output Data Register
+        ptr::write_volatile(odr, ptr::read_volatile(odr) | (1 << LED_PIN));
+    }
+}
+
+/// Turn LED off
+pub fn led_off() {
+    unsafe {
+        let odr = (GPIO_PORT_BASE + 0x14) as *mut u32;
+        ptr::write_volatile(odr, ptr::read_volatile(odr) & !(1 << LED_PIN));
+    }
+}
+
+/// Toggle LED state
+pub fn toggle_led() {
+    unsafe {
+        let odr = (GPIO_PORT_BASE + 0x14) as *mut u32;
+        ptr::write_volatile(odr, ptr::read_volatile(odr) ^ (1 << LED_PIN));
+    }
+}