diff --git a/.gitea/workflows/build.yaml b/.gitea/workflows/build.yaml
index 00c53e6..ab52085 100644
--- a/.gitea/workflows/build.yaml
+++ b/.gitea/workflows/build.yaml
@@ -31,4 +31,9 @@ jobs:
           name: firmware
           path: |
             build/*.hex
-            build/*.bin
\ No newline at end of file
+            build/*.bin
+      
+      - name: Upload Firmware
+        env:
+          SERVER_KEY: ${{ secrets.SERVER_KEY }}
+        run: python3 tools/upload_firmware.py $SERVER_KEY
\ No newline at end of file
diff --git a/Application/BSP/BSP_POWER.c b/Application/BSP/BSP_POWER.c
index 438a73e..6445097 100644
--- a/Application/BSP/BSP_POWER.c
+++ b/Application/BSP/BSP_POWER.c
@@ -10,7 +10,7 @@
 #include "cmsis_os2.h"
 #include "BSP_GPIO.h"
 #include "BSP_ADC.h"
-
+#include "BSP_SDLogger.h"
 #define LPTIM_CLK 500     // Hz
 #define SLEEP_TICK_TIME 1  // seconds to wait
 #define STAY_AWAKE_TIME 60 // seconds to stay awake without K15
@@ -52,6 +52,8 @@ void BSP_POWER_WakeUp() {
 */
 void BSP_POWER_EnterStandby() {
 
+    BSP_SDLogger_Flush();
+
     // stop the sytem interrupts
     __disable_irq();
 
diff --git a/Application/BSP/BSP_SDLogger.c b/Application/BSP/BSP_SDLogger.c
index 3efa7e6..15c6903 100644
--- a/Application/BSP/BSP_SDLogger.c
+++ b/Application/BSP/BSP_SDLogger.c
@@ -4,7 +4,7 @@
 #include "stdio.h"
 #include "string.h"
 
-uint8_t block_buffer[512] = {0};
+uint8_t block_buffer[2048] = {0};
 size_t block_buffer_index = 0;
 char file_name[20];
 
@@ -41,7 +41,7 @@ void BSP_SDLogger_Flush() {
     
         // open the file
         FIL file;
-        FRESULT res = f_open(&file, file_name, FA_WRITE);
+        FRESULT res = f_open(&file, file_name, FA_OPEN_APPEND | FA_WRITE );
         if (res != FR_OK) {
             ULOG_ERROR("Failed to open file %s", file_name);
         }
@@ -75,6 +75,7 @@ void  BSP_SDLogger_Write(char *data, size_t length) {
     if (length > remaining_size) {
         // write the remaining space to the buffer
         memcpy(&block_buffer[block_buffer_index], data, remaining_size);
+        block_buffer_index += remaining_size;
         // write the buffer to the file
         BSP_SDLogger_Flush();
         // write the remaining data to the buffer
diff --git a/Application/BSP/BSP_SDLogger.h b/Application/BSP/BSP_SDLogger.h
index a4b6647..0adcd4a 100644
--- a/Application/BSP/BSP_SDLogger.h
+++ b/Application/BSP/BSP_SDLogger.h
@@ -9,4 +9,6 @@
 void BSP_SDLogger_Init(int log_number);
 
 
-void BSP_SDLogger_Write(char *data, size_t length);
\ No newline at end of file
+void BSP_SDLogger_Write(char *data, size_t length);
+
+void BSP_SDLogger_Flush();
\ No newline at end of file
diff --git a/Core/Src/freertos.c b/Core/Src/freertos.c
index b5d5286..48031dc 100644
--- a/Core/Src/freertos.c
+++ b/Core/Src/freertos.c
@@ -187,7 +187,7 @@ void StartDefaultTask(void *argument)
     ULOG_INFO(output);
   }
 
-  
+  BSP_SDLogger_Init(counter);
 
   char  INA_LOG[72];
 
diff --git a/tools/upload_firmware.py b/tools/upload_firmware.py
new file mode 100644
index 0000000..1143235
--- /dev/null
+++ b/tools/upload_firmware.py
@@ -0,0 +1,71 @@
+import hmac
+import hashlib
+import sys
+from pathlib import Path
+import requests
+import subprocess
+import base64
+
+def load_secret_key(keyb64: str):
+    # Decode the base64 encoded key
+    decoded_key = base64.b64decode(keyb64)
+
+    return decoded_key
+
+def compute_hmac(file_path, secret_key):
+    """Compute the HMAC of a file using HMAC-SHA256."""
+    hmac_obj = hmac.new(secret_key, digestmod=hashlib.sha256)
+    with open(file_path, 'rb') as f:
+        while chunk := f.read(4096):
+            hmac_obj.update(chunk)
+    return hmac_obj.hexdigest()
+
+def upload_file(url, file_path, secret_key):
+    """Upload a file to the server with an HMAC signature."""
+    # Compute HMAC of the file
+    signature = compute_hmac(file_path, secret_key)
+    print(signature)
+    # Prepare headers
+    headers = {'X-Signature': signature}
+    
+    # Read file and prepare files dictionary for request
+    with open(file_path, 'rb') as f:
+        files = {'file': (Path(file_path).name, f)}
+        response = requests.post(url, files=files, headers=headers)
+    
+    return response
+
+
+def get_short_git_commit_hash():
+    try:
+        # Run the Git command to get the short commit hash
+        result = subprocess.run(['git', 'rev-parse', '--short', 'HEAD'], stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True, check=True)
+        # Extract and return the commit hash
+        return result.stdout.strip()
+    except subprocess.CalledProcessError as e:
+        print(f"Error getting Git commit hash: {e}")
+        return None
+
+if __name__ == "__main__":
+    url = "https://fw.revwal.de/master/upload"  # Adjust this to your server's URL
+
+
+    fw_path = "build/CLS_Master.bin"  # Path to the file you want to upload
+    
+    # Get the Git commit hash
+    commit_hash = get_short_git_commit_hash()
+    if commit_hash is None:
+        print("Error: Could not get Git commit hash")
+        sys.exit(1)
+
+    # replace the file name with the commit hash
+    file_path = fw_path.replace("CLS_Master", commit_hash)
+
+    # copy the file to the new name
+    subprocess.run(['cp', fw_path, file_path])
+    
+    
+    secret_key = load_secret_key(sys.argv[1])
+    
+    response = upload_file(url, file_path, secret_key)
+    print(f"Server response: {response.text}")
\ No newline at end of file