diff --git a/build/final.elf b/build/final.elf
index bdc732f..8e6b73c 100755
Binary files a/build/final.elf and b/build/final.elf differ
diff --git a/build/final.elf.map b/build/final.elf.map
index ffd0fa8..bfba6d0 100644
--- a/build/final.elf.map
+++ b/build/final.elf.map
@@ -157,7 +157,7 @@ LOAD build/usart.o
                 0x08000000                interrupt_vector_table
                 0x08000198                        . = ALIGN (0x4)
 
-.text           0x08000198      0x4f0
+.text           0x08000198      0x4e4
                 0x08000198                        . = ALIGN (0x4)
  *(.text)
  *(.text.*)
@@ -254,44 +254,44 @@ LOAD build/usart.o
                 0x080004e4       0x20 build/timer.o
                 0x080004e4                tim4_start
  .text.usart2_init
-                0x08000504       0xf8 build/usart.o
+                0x08000504       0xec build/usart.o
                 0x08000504                usart2_init
  .text.usart2_start
-                0x080005fc       0x20 build/usart.o
-                0x080005fc                usart2_start
+                0x080005f0       0x20 build/usart.o
+                0x080005f0                usart2_start
  .text.usart2_write_byte
-                0x0800061c       0x30 build/usart.o
-                0x0800061c                usart2_write_byte
+                0x08000610       0x30 build/usart.o
+                0x08000610                usart2_write_byte
  .text.usart2_write
-                0x0800064c       0x2a build/usart.o
-                0x0800064c                usart2_write
+                0x08000640       0x2a build/usart.o
+                0x08000640                usart2_write
  *(.rodata)
- *fill*         0x08000676        0x2 
- .rodata        0x08000678        0xe build/main.o
+ *fill*         0x0800066a        0x2 
+ .rodata        0x0800066c        0xe build/main.o
  *(.rodata.*)
-                0x08000688                        . = ALIGN (0x4)
- *fill*         0x08000686        0x2 
-                0x08000688                        _data_addr = LOADADDR (.data)
+                0x0800067c                        . = ALIGN (0x4)
+ *fill*         0x0800067a        0x2 
+                0x0800067c                        _data_addr = LOADADDR (.data)
 
-.glue_7         0x08000688        0x0
- .glue_7        0x08000688        0x0 linker stubs
+.glue_7         0x0800067c        0x0
+ .glue_7        0x0800067c        0x0 linker stubs
 
-.glue_7t        0x08000688        0x0
- .glue_7t       0x08000688        0x0 linker stubs
+.glue_7t        0x0800067c        0x0
+ .glue_7t       0x0800067c        0x0 linker stubs
 
-.vfp11_veneer   0x08000688        0x0
- .vfp11_veneer  0x08000688        0x0 linker stubs
+.vfp11_veneer   0x0800067c        0x0
+ .vfp11_veneer  0x0800067c        0x0 linker stubs
 
-.v4_bx          0x08000688        0x0
- .v4_bx         0x08000688        0x0 linker stubs
+.v4_bx          0x0800067c        0x0
+ .v4_bx         0x0800067c        0x0 linker stubs
 
-.iplt           0x08000688        0x0
- .iplt          0x08000688        0x0 build/main.o
+.iplt           0x0800067c        0x0
+ .iplt          0x0800067c        0x0 build/main.o
 
-.rel.dyn        0x08000688        0x0
- .rel.iplt      0x08000688        0x0 build/main.o
+.rel.dyn        0x0800067c        0x0
+ .rel.iplt      0x0800067c        0x0 build/main.o
 
-.data           0x20000000        0x0 load address 0x08000688
+.data           0x20000000        0x0 load address 0x0800067c
                 0x20000000                        . = ALIGN (0x4)
                 0x20000000                        _data_start = .
  *(.data)
@@ -299,10 +299,10 @@ LOAD build/usart.o
                 0x20000000                        . = ALIGN (0x4)
                 0x20000000                        _data_end = .
 
-.igot.plt       0x20000000        0x0 load address 0x08000688
+.igot.plt       0x20000000        0x0 load address 0x0800067c
  .igot.plt      0x20000000        0x0 build/main.o
 
-.bss            0x20000000        0x0 load address 0x08000688
+.bss            0x20000000        0x0 load address 0x0800067c
                 0x20000000                        . = ALIGN (0x4)
                 0x20000000                        _bss_start = .
  *(.bss)
@@ -381,12 +381,12 @@ LOAD linker stubs
  .debug_macro   0x00003cb3      0xb74 build/usart.o
  .debug_macro   0x00004827       0x82 build/usart.o
 
-.debug_line     0x00000000      0x666
+.debug_line     0x00000000      0x661
  .debug_line    0x00000000      0x116 build/gpio.o
  .debug_line    0x00000116      0x1e4 build/main.o
  .debug_line    0x000002fa       0xea build/startup.o
  .debug_line    0x000003e4       0xdf build/timer.o
- .debug_line    0x000004c3      0x1a3 build/usart.o
+ .debug_line    0x000004c3      0x19e build/usart.o
 
 .debug_str      0x00000000     0x63e6
  .debug_str     0x00000000     0x5508 build/gpio.o
diff --git a/build/usart.S b/build/usart.S
index fdf12ba..e3a37e9 100644
--- a/build/usart.S
+++ b/build/usart.S
@@ -121,56 +121,49 @@ usart2_init:
 	.loc 1 28 41
 	movs	r2, #0
 	str	r2, [r3, #20]
-	.loc 1 50 35
-	ldr	r3, .L2+8
-	ldr	r3, [r3, #12]
-	ldr	r2, .L2+8
-	.loc 1 50 41
-	orr	r3, r3, #32768
-	str	r3, [r2, #12]
-	.loc 1 52 35
-	ldr	r3, .L2+8
-	ldr	r3, [r3, #8]
-	ldr	r2, .L2+8
-	.loc 1 52 41
-	bic	r3, r3, #65280
-	bic	r3, r3, #240
-	str	r3, [r2, #8]
-	.loc 1 53 35
-	ldr	r3, .L2+8
-	ldr	r3, [r3, #8]
-	ldr	r2, .L2+8
-	.loc 1 53 41
-	orr	r3, r3, #832
-	str	r3, [r2, #8]
 	.loc 1 54 35
 	ldr	r3, .L2+8
 	ldr	r3, [r3, #8]
 	ldr	r2, .L2+8
 	.loc 1 54 41
-	bic	r3, r3, #7
+	bic	r3, r3, #65280
+	bic	r3, r3, #240
 	str	r3, [r2, #8]
 	.loc 1 55 35
 	ldr	r3, .L2+8
-	ldr	r2, .L2+8
 	ldr	r3, [r3, #8]
+	ldr	r2, .L2+8
 	.loc 1 55 41
+	orr	r3, r3, #832
 	str	r3, [r2, #8]
 	.loc 1 58 35
 	ldr	r3, .L2+8
-	ldr	r3, [r3, #12]
+	ldr	r3, [r3, #8]
 	ldr	r2, .L2+8
 	.loc 1 58 41
-	orr	r3, r3, #8
-	str	r3, [r2, #12]
+	bic	r3, r3, #7
+	str	r3, [r2, #8]
 	.loc 1 59 35
 	ldr	r3, .L2+8
+	ldr	r2, .L2+8
+	ldr	r3, [r3, #8]
+	.loc 1 59 41
+	str	r3, [r2, #8]
+	.loc 1 62 35
+	ldr	r3, .L2+8
 	ldr	r3, [r3, #12]
 	ldr	r2, .L2+8
-	.loc 1 59 41
+	.loc 1 62 41
+	orr	r3, r3, #8
+	str	r3, [r2, #12]
+	.loc 1 63 35
+	ldr	r3, .L2+8
+	ldr	r3, [r3, #12]
+	ldr	r2, .L2+8
+	.loc 1 63 41
 	orr	r3, r3, #4
 	str	r3, [r2, #12]
-	.loc 1 60 1
+	.loc 1 64 1
 	nop
 	mov	sp, r7
 	.cfi_def_cfa_register 13
@@ -197,7 +190,7 @@ usart2_init:
 	.type	usart2_start, %function
 usart2_start:
 .LFB1:
-	.loc 1 62 25
+	.loc 1 66 25
 	.cfi_startproc
 	@ args = 0, pretend = 0, frame = 0
 	@ frame_needed = 1, uses_anonymous_args = 0
@@ -207,14 +200,14 @@ usart2_start:
 	.cfi_offset 7, -4
 	add	r7, sp, #0
 	.cfi_def_cfa_register 7
-	.loc 1 63 35
+	.loc 1 67 35
 	ldr	r3, .L5
 	ldr	r3, [r3, #12]
 	ldr	r2, .L5
-	.loc 1 63 41
+	.loc 1 67 41
 	orr	r3, r3, #8192
 	str	r3, [r2, #12]
-	.loc 1 64 1
+	.loc 1 68 1
 	nop
 	mov	sp, r7
 	.cfi_def_cfa_register 13
@@ -239,7 +232,7 @@ usart2_start:
 	.type	usart2_write_byte, %function
 usart2_write_byte:
 .LFB2:
-	.loc 1 66 35
+	.loc 1 70 35
 	.cfi_startproc
 	@ args = 0, pretend = 0, frame = 8
 	@ frame_needed = 1, uses_anonymous_args = 0
@@ -253,23 +246,23 @@ usart2_write_byte:
 	.cfi_def_cfa_register 7
 	mov	r3, r0
 	strb	r3, [r7, #7]
-	.loc 1 68 35
+	.loc 1 72 35
 	ldr	r2, .L9
-	.loc 1 68 40
+	.loc 1 72 40
 	ldrb	r3, [r7, #7]	@ zero_extendqisi2
 	str	r3, [r2, #4]
-	.loc 1 71 9
+	.loc 1 75 9
 	nop
 .L8:
-	.loc 1 71 43 discriminator 1
+	.loc 1 75 43 discriminator 1
 	ldr	r3, .L9
 	ldr	r3, [r3]
-	.loc 1 71 48 discriminator 1
+	.loc 1 75 48 discriminator 1
 	and	r3, r3, #128
-	.loc 1 71 60 discriminator 1
+	.loc 1 75 60 discriminator 1
 	cmp	r3, #0
 	beq	.L8
-	.loc 1 73 1
+	.loc 1 77 1
 	nop
 	nop
 	adds	r7, r7, #12
@@ -297,7 +290,7 @@ usart2_write_byte:
 	.type	usart2_write, %function
 usart2_write:
 .LFB3:
-	.loc 1 75 30
+	.loc 1 79 30
 	.cfi_startproc
 	@ args = 0, pretend = 0, frame = 8
 	@ frame_needed = 1, uses_anonymous_args = 0
@@ -310,24 +303,24 @@ usart2_write:
 	add	r7, sp, #0
 	.cfi_def_cfa_register 7
 	str	r0, [r7, #4]
-	.loc 1 76 9
+	.loc 1 80 9
 	b	.L12
 .L13:
-	.loc 1 76 38 discriminator 2
+	.loc 1 80 38 discriminator 2
 	ldr	r3, [r7, #4]
 	adds	r2, r3, #1
 	str	r2, [r7, #4]
-	.loc 1 76 16 discriminator 2
+	.loc 1 80 16 discriminator 2
 	ldrb	r3, [r3]	@ zero_extendqisi2
 	mov	r0, r3
 	bl	usart2_write_byte
 .L12:
-	.loc 1 76 10 discriminator 1
+	.loc 1 80 10 discriminator 1
 	ldr	r3, [r7, #4]
 	ldrb	r3, [r3]	@ zero_extendqisi2
 	cmp	r3, #0
 	bne	.L13
-	.loc 1 77 1
+	.loc 1 81 1
 	nop
 	nop
 	adds	r7, r7, #8
@@ -732,7 +725,7 @@ usart2_write:
 	.uleb128 0xe
 	.4byte	.LASF1000
 	.byte	0x1
-	.byte	0x4b
+	.byte	0x4f
 	.byte	0x6
 	.4byte	.LFB3
 	.4byte	.LFE3-.LFB3
@@ -741,7 +734,7 @@ usart2_write:
 	.4byte	0x320
 	.uleb128 0x7
 	.ascii	"buf\000"
-	.byte	0x4b
+	.byte	0x4f
 	.byte	0x19
 	.4byte	0x320
 	.uleb128 0x2
@@ -758,7 +751,7 @@ usart2_write:
 	.uleb128 0x10
 	.4byte	.LASF1001
 	.byte	0x1
-	.byte	0x42
+	.byte	0x46
 	.byte	0x6
 	.4byte	.LFB2
 	.4byte	.LFE2-.LFB2
@@ -767,7 +760,7 @@ usart2_write:
 	.4byte	0x350
 	.uleb128 0x7
 	.ascii	"c\000"
-	.byte	0x42
+	.byte	0x46
 	.byte	0x20
 	.4byte	0x88
 	.uleb128 0x2
@@ -776,7 +769,7 @@ usart2_write:
 	.byte	0
 	.uleb128 0x8
 	.4byte	.LASF1002
-	.byte	0x3e
+	.byte	0x42
 	.4byte	.LFB1
 	.4byte	.LFE1-.LFB1
 	.uleb128 0x1
diff --git a/build/usart.i b/build/usart.i
index a99d2e7..4a86ecc 100644
--- a/build/usart.i
+++ b/build/usart.i
@@ -2266,11 +2266,11 @@ void usart2_init(void) {
   ((struct usart *) (0x40004400U))->CR1 = 0;
   ((struct usart *) (0x40004400U))->CR2 = 0;
   ((struct usart *) (0x40004400U))->CR3 = 0;
-# 50 "src/usart.c"
-  ((struct usart *) (0x40004400U))->CR1 |= (1 << 15);
-
+# 54 "src/usart.c"
   ((struct usart *) (0x40004400U))->BRR &= ~((0b111111111111) << 4);
   ((struct usart *) (0x40004400U))->BRR |= (0x34 << 4);
+
+
   ((struct usart *) (0x40004400U))->BRR &= ~((0b111) << 0);
   ((struct usart *) (0x40004400U))->BRR |= (0x0 << 0);
 
diff --git a/build/usart.o b/build/usart.o
index c1649ba..6e26695 100644
Binary files a/build/usart.o and b/build/usart.o differ
diff --git a/flake.nix b/flake.nix
index 557d069..83fd782 100644
--- a/flake.nix
+++ b/flake.nix
@@ -5,36 +5,38 @@
     nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
   };
 
-  outputs = { nixpkgs, ... }:
+  outputs =
+    { nixpkgs, ... }:
     let
       systems = [ "x86_64-linux" ];
     in
-      {
-        config = {
-          nixpkgs.config.allowUnfree = true;
-        };
-
-        devShells = nixpkgs.lib.genAttrs systems (system:
-          let
-            # pkgs = nixpkgs.legacyPackages.${system};
-            pkgs = import nixpkgs {
-              inherit system;
-              config.allowUnfree = true;
-            };
-          in
-            {
-              default = pkgs.mkShell {
-                packages = [
-                  pkgs.gnumake
-                  pkgs.gcc-arm-embedded
-                  pkgs.stlink
-                  pkgs.gdb
-                  pkgs.openocd
-                  pkgs.stm32cubemx
-                  pkgs.gdbgui
-                ];
-              };
-            }
-        );
+    {
+      config = {
+        nixpkgs.config.allowUnfree = true;
       };
+
+      devShells = nixpkgs.lib.genAttrs systems (
+        system:
+        let
+          # pkgs = nixpkgs.legacyPackages.${system};
+          pkgs = import nixpkgs {
+            inherit system;
+            config.allowUnfree = true;
+          };
+        in
+        {
+          default = pkgs.mkShell {
+            packages = [
+              pkgs.gnumake
+              pkgs.gcc-arm-embedded
+              pkgs.stlink
+              pkgs.gdb
+              pkgs.openocd
+              pkgs.stm32cubemx
+              pkgs.gdbgui
+            ];
+          };
+        }
+      );
+    };
 }
diff --git a/src/usart.c b/src/usart.c
index 6839f03..32bc316 100644
--- a/src/usart.c
+++ b/src/usart.c
@@ -28,29 +28,33 @@ void usart2_init(void) {
   USART2->CR3 = 0;
 
   // Calculate Baud rate:
-  // baud = f_clock / (8 * (2 - OVER8) * USARTDIV); =>
-  // (8 * (2 - OVER8) * USARTDIV) = f_clock / baud; =>
-  // USARTDIV = (f_clock / (baud * (8 * (2 - OVER8))); =>
+  // baud = f_clck / (8 * (2 - OVER8) * USARTDIV) =>
+  // (8 * (2 - OVER8) * USARTDIV) = f_clock / baud =>
+  // USARTDIV = (f_clock / (baud * (8 * (2 - OVER8)))
 
   // Target Baud rate = 115200, f_clock = 48MHz
 
   // With OVER8 = 1 (oversampling by 8)
-  // USARTDIV = (48E6 / (115200 * (8 * (2 - 1))) = 52.083
-  // mantissa = 52
-  // fraction = 0.083 * 8 = 0.664 ~= 1
+  // USARTDIV = (48E6 / (115200 * (8 * (2 - 0)))) = 26.0416666
+  // mantissa = 26
+  // fraction = 0.041666 * 8 = 0.33328 ~= 0
 
-  // rounding fraction up: USARTDIV = 53
-  // baud = 48E6 / (8 * (52 + 1)) = 113207.54716981133
-  // error of 0.1% (115200 / 113207.54716981133)
+  // rounding fraction up: USARTDIV = 26
+  // baud = 48E6 / (8 * 2 * 26) = 115384.61538461539
+  // error of 0.001% (115384.61538461539 / 115200 ) = 1.001602564102564
 
-  // rounding fraction down: USARTDIV = 52
-  // baud = 48E6 / (8 * 52) = 115384.61538461539
-  // error of 0.001% (115384.61538461539 / 115200)
 
-  USART2->CR1 |= USART_CR1_OVER8_8;
+  // baud = f_clck / (8 * (2 - OVER8) * USARTDIV) */
+  // baud * ((8 * (2 - OVER8) * USARTDIV)) = f_clck */
+  // 393400 * (8 * 2 * 26) = 163654400
+
+
+  /* USART2->CR1 |= USART_CR1_OVER8_8; */
 
   USART2->BRR &= ~(USART_BRR_MANTISSA_MASK << USART_BRR_MANTISSA_BIT);
   USART2->BRR |= (0x34 << USART_BRR_MANTISSA_BIT);
+  /* USART2->BRR |= (0x69 << USART_BRR_MANTISSA_BIT); */
+  /* USART2->BRR |= (0x1A << USART_BRR_MANTISSA_BIT); */
   USART2->BRR &= ~(USART_BRR_FRACTION_MASK << USART_BRR_FRACTION_BIT);
   USART2->BRR |= (0x0 << USART_BRR_FRACTION_BIT);