diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37b70fd..920fa4a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,7 +7,7 @@ project(stm32)
 
 add_subdirectory(app)   #application
 add_subdirectory(bsp)   #board support package, lwip
-add_subdirectory(lib)   #stm32f4xx library
+add_subdirectory(libs/stm32f4xx)   #stm32f4xx library
 
 
 
diff --git a/app/CMakeLists.txt b/app/CMakeLists.txt
index f6e788a..e516791 100644
--- a/app/CMakeLists.txt
+++ b/app/CMakeLists.txt
@@ -1,9 +1,18 @@
 set(elf_file stm32.elf)
 
-set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/nanopb/extra)
-find_package(Nanopb REQUIRED)
+# include(FetchContent)
 
-nanopb_generate_cpp(TARGET proto simple.proto)
+# FetchContent_Declare(nanopb
+#     GIT_REPOSITORY https://github.com/nanopb/nanopb
+#     GIT_TAG        master
+# )
+
+# FetchContent_MakeAvailable(nanopb)
+
+# set(CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/nanopb/extra)
+# find_package(Nanopb REQUIRED)
+
+# nanopb_generate_cpp(TARGET proto simple.proto)
 
 add_executable(${elf_file}    
     main.c
@@ -12,15 +21,13 @@ add_executable(${elf_file}
 
 target_link_libraries(${elf_file} PUBLIC  
     bsp
-    proto
+    # proto
 )
 
 target_include_directories(${elf_file} PRIVATE 
     ${CMAKE_CURRENT_SOURCE_DIR}
 )
 
-
-
 set(EXECUTABLE ${PROJECT_NAME}.elf)
 
 add_custom_command(TARGET ${EXECUTABLE}
diff --git a/app/main.c b/app/main.c
index c9b392f..093866f 100644
--- a/app/main.c
+++ b/app/main.c
@@ -1,36 +1,37 @@
 #include "../bsp/bsp.h"
-#include <pb_encode.h>
-#include <pb_decode.h>
-#include "simple.pb.h"
+// #include <pb_encode.h>
+// #include <pb_decode.h>
+// #include "simple.pb.h"
 
-void serialzie() {
-    /* This is the buffer where we will store our message. */
-    uint8_t buffer[128];
-    size_t message_length;
-    bool status;
+// void serialzie() {
+//     /* This is the buffer where we will store our message. */
+//     uint8_t buffer[128];
+//     size_t message_length;
+//     bool status;
     
-    /* Encode our message */
-    {
-        SimpleMessage message = SimpleMessage_init_zero;
+//     /* Encode our message */
+//     {
+//         SimpleMessage message = SimpleMessage_init_zero;
         
-        /* Create a stream that will write to our buffer. */
-        pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
+//         /* Create a stream that will write to our buffer. */
+//         pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
         
-        /* Fill in the lucky number */
-        message.number = 42;
-        /* Now we are ready to encode the message! */
-        status = pb_encode(&stream, SimpleMessage_fields, &message);
-        message_length = stream.bytes_written;
-        udp_send_data(buffer, message_length);
-        /* Then just check for any errors.. */
-        if (!status)
-        {
-            printf("Encoding failed: %s\n", PB_GET_ERROR(&stream));
-            return 1;
-        }
-    }    
-    return 0;
-}
+//         /* Fill in the lucky number */
+//         message.number = 42;
+//         /* Now we are ready to encode the message! */
+//         status = pb_encode(&stream, SimpleMessage_fields, &message);
+//         message_length = stream.bytes_written;
+//         printf('%d\r\n', buffer);
+//         // udp_send_data(buffer, message_length);
+//         /* Then just check for any errors.. */
+//         if (!status)
+//         {
+//             printf("Encoding failed: %s\n", PB_GET_ERROR(&stream));
+//             return 1;
+//         }
+//     }    
+//     return 0;
+// }
 
 int main(void)
 {
@@ -41,14 +42,14 @@ int main(void)
   
   while (1)
   {
-    lwipProcess(); // poll for ethernet rx and timer operations.
+    lwipProcess(); 
     const char *data = "Hello, world!";
     sprintf(numStr, "%d", cnt++);
     char* strCat = strcat(data, numStr);
-    udp_send_data(numStr, strlen(numStr));
+    // udp_send_data(numStr, strlen(numStr));
     // serialzie();
     GPIO_ToggleBits(GPIOB, GPIO_Pin_14);
-    delay(500);
+    delay(100);
   }
 
 }
diff --git a/app/simple.proto b/app/simple.proto
index da1456b..4361881 100644
--- a/app/simple.proto
+++ b/app/simple.proto
@@ -1,10 +1,7 @@
-// A very simple protocol definition, consisting of only
-// one message.
-
 syntax = "proto2";
 
 message SimpleMessage {
     optional string project = 1 [default = "controls"];
-    required int32 number = 2;
+    required  int32 number = 2;
 }
 
diff --git a/bsp/bsp.c b/bsp/bsp.c
index 031e2e8..bac31d1 100644
--- a/bsp/bsp.c
+++ b/bsp/bsp.c
@@ -60,9 +60,6 @@ void uartInit(void)
   GPIO_PinAFConfig(GPIOD, GPIO_PinSource5, GPIO_AF_USART2);
   GPIO_PinAFConfig(GPIOD, GPIO_PinSource6, GPIO_AF_USART2);
 
-  // NVIC_SetPriority(USART2_IRQn, 0);
-  // NVIC_EnableIRQ(USART2_IRQn);
-
   USART_InitTypeDef usart;
   usart.USART_BaudRate = 115200;
   usart.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
@@ -139,6 +136,6 @@ void boardInit() {
     uartInit();
     ethInit();
     tim_init();
-    printf("Starting main loop..\r\n");
     lwipInit();
+    printf("Starting app..\r\n");
 }
\ No newline at end of file
diff --git a/bsp/bsp.h b/bsp/bsp.h
index 3146f0c..bca0aa2 100644
--- a/bsp/bsp.h
+++ b/bsp/bsp.h
@@ -8,6 +8,7 @@
 #include "stm32f4xx_dma.h"
 #include "stm32f4xx_tim.h"
 #include "stm32f4xx_flash.h"
+#include "stm32f4xx_hal_eth.h"
 #include "lwip/lwip.h"
 
 typedef enum  {
diff --git a/bsp/lwip/ethernetif.h b/bsp/lwip/ethernetif.h
index b13f73c..0b4455c 100644
--- a/bsp/lwip/ethernetif.h
+++ b/bsp/lwip/ethernetif.h
@@ -4,11 +4,9 @@
 
 #include "lwip/err.h"
 #include "lwip/netif.h"
-#include "stm32f4xx_hal_eth.h"
-#include "../bsp/bsp.h"
+#include "bsp.h"
 
 err_t ethernetif_init(struct netif *netif);
-
 void ethernetif_input(struct netif *netif);
 void ethernetif_update_config(struct netif *netif);
 void ethernetif_notify_conn_changed(struct netif *netif);
diff --git a/bsp/lwip/lwip.c b/bsp/lwip/lwip.c
index b0057ca..663a72e 100644
--- a/bsp/lwip/lwip.c
+++ b/bsp/lwip/lwip.c
@@ -8,11 +8,13 @@
 #include "lwip/timeouts.h"
 #include "netif/etharp.h"
 
+#define UDP_RX_BUFFER_SIZE 128
+
 void Error_Handler(void);
 
 struct udp_pcb *upcb;
 ip_addr_t remote_ip;
-u16_t remote_port;
+const uint16_t remote_port = 5678;
 
 struct netif gnetif;
 ip4_addr_t ipaddr;
@@ -22,32 +24,45 @@ uint8_t IP_ADDRESS[4];
 uint8_t NETMASK_ADDRESS[4];
 uint8_t GATEWAY_ADDRESS[4];
 
+static char udp_receive_buffer[UDP_RX_BUFFER_SIZE];
+
+void udp_receive_callback(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t *addr, u16_t port);
+
+void udp_receive_callback(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t *addr, u16_t port) {
+  strncpy(udp_receive_buffer,p->payload,p->len);
+  udp_receive_buffer[p->len]=0;
+  // printf("Test\r\n");
+  printf("%s\r\n", udp_receive_buffer);
+  pbuf_free(p);
+  GPIO_ToggleBits(GPIOD, GPIO_Pin_0);
+}
+
 void udpServer_init(void)
 {
-	// UDP Control Block structure
-   err_t err;
+  ip_addr_t local_ip;
+  uint16_t local_port = 1234;
+  uint16_t remote_port = 5678;
+  err_t err;
 
-   /* 1. Create a new UDP control block  */
-   upcb = udp_new();
-   ip_addr_t local_ip;
-   u16_t local_port;
-   local_port = 1234;
-   /* 2. Bind the upcb to the local port */
-   IP_ADDR4(&local_ip, 192, 168, 1, 66);
+  upcb = udp_new();
 
-   err = udp_bind(upcb, &local_ip, local_port);  
-
-   /* 3. Set a receive callback for the upcb */
-   if(err == ERR_OK)
-   {
-	  IP4_ADDR(&remote_ip, 192, 168, 1, 111);
-	  remote_port = 5678;
-
-   }
-   else
-   {
-	   udp_remove(upcb);
-   }
+  if(upcb != NULL) {
+    IP_ADDR4(&local_ip, 192, 168, 1, 66);
+    err = udp_bind(upcb, &local_ip, local_port);  
+    if (err == ERR_OK) {
+      // printf("UDP bind\r\n");
+    }
+    // IP4_ADDR(&remote_ip, 192, 168, 1, 111);
+    // err= udp_connect(upcb, &remote_ip, remote_port);
+    if (err == ERR_OK) {
+      // printf("UDP connect\r\n");
+      udp_recv(upcb, udp_receive_callback, NULL);
+    }
+  }
+  else
+  {
+    udp_remove(upcb);
+  }
 }
 
 void udp_send_data(const char *data, u16_t len)
@@ -68,6 +83,8 @@ void udp_send_data(const char *data, u16_t len)
   }
 }
 
+
+
 void lwipInit(void)
 {
 	  IP_ADDRESS[0] = 192;
diff --git a/bsp/lwip/lwipopts.h b/bsp/lwip/lwipopts.h
index 645de2a..6830e7f 100644
--- a/bsp/lwip/lwipopts.h
+++ b/bsp/lwip/lwipopts.h
@@ -147,8 +147,11 @@
 #define LWIP_DEBUG 1
 
 #define LWIP_TCP 0
-
+#define LWIP_UDP 1
+#define MEMP_NUM_UDP_PCB 6 
 #define LWIP_NETIF_LINK_CALLBACK 1
+#define PBUF_POOL_SIZE 16
+#define PBUF_POOL_BUFSIZE 1200
 /* USER CODE END 1 */
 
 #ifdef __cplusplus
diff --git a/bsp/lwip/src/core/udp.c b/bsp/lwip/src/core/udp.c
index 0059259..9886034 100644
--- a/bsp/lwip/src/core/udp.c
+++ b/bsp/lwip/src/core/udp.c
@@ -388,7 +388,7 @@ udp_input(struct pbuf *p, struct netif *inp)
       }
 #endif /* SO_REUSE && SO_REUSE_RXTOALL */
       /* callback */
-      if (pcb->recv != NULL) {
+    if (pcb->recv != NULL) {
         /* now the recv function is responsible for freeing p */
         pcb->recv(pcb->recv_arg, pcb, p, ip_current_src_addr(), src);
       } else {
@@ -396,7 +396,8 @@ udp_input(struct pbuf *p, struct netif *inp)
         pbuf_free(p);
         goto end;
       }
-    } else {
+    } 
+    else {
       LWIP_DEBUGF(UDP_DEBUG | LWIP_DBG_TRACE, ("udp_input: not for us.\n"));
 
 #if LWIP_ICMP || LWIP_ICMP6
diff --git a/lib/CMakeLists.txt b/libs/stm32f4xx/CMakeLists.txt
similarity index 100%
rename from lib/CMakeLists.txt
rename to libs/stm32f4xx/CMakeLists.txt
diff --git a/lib/inc/CMSIS/arm_common_tables.h b/libs/stm32f4xx/inc/CMSIS/arm_common_tables.h
similarity index 100%
rename from lib/inc/CMSIS/arm_common_tables.h
rename to libs/stm32f4xx/inc/CMSIS/arm_common_tables.h
diff --git a/lib/inc/CMSIS/arm_const_structs.h b/libs/stm32f4xx/inc/CMSIS/arm_const_structs.h
similarity index 100%
rename from lib/inc/CMSIS/arm_const_structs.h
rename to libs/stm32f4xx/inc/CMSIS/arm_const_structs.h
diff --git a/lib/inc/CMSIS/arm_math.h b/libs/stm32f4xx/inc/CMSIS/arm_math.h
similarity index 100%
rename from lib/inc/CMSIS/arm_math.h
rename to libs/stm32f4xx/inc/CMSIS/arm_math.h
diff --git a/lib/inc/CMSIS/core_cm0.h b/libs/stm32f4xx/inc/CMSIS/core_cm0.h
similarity index 100%
rename from lib/inc/CMSIS/core_cm0.h
rename to libs/stm32f4xx/inc/CMSIS/core_cm0.h
diff --git a/lib/inc/CMSIS/core_cm0plus.h b/libs/stm32f4xx/inc/CMSIS/core_cm0plus.h
similarity index 100%
rename from lib/inc/CMSIS/core_cm0plus.h
rename to libs/stm32f4xx/inc/CMSIS/core_cm0plus.h
diff --git a/lib/inc/CMSIS/core_cm3.h b/libs/stm32f4xx/inc/CMSIS/core_cm3.h
similarity index 100%
rename from lib/inc/CMSIS/core_cm3.h
rename to libs/stm32f4xx/inc/CMSIS/core_cm3.h
diff --git a/lib/inc/CMSIS/core_cm4.h b/libs/stm32f4xx/inc/CMSIS/core_cm4.h
similarity index 100%
rename from lib/inc/CMSIS/core_cm4.h
rename to libs/stm32f4xx/inc/CMSIS/core_cm4.h
diff --git a/lib/inc/CMSIS/core_cm7.h b/libs/stm32f4xx/inc/CMSIS/core_cm7.h
similarity index 100%
rename from lib/inc/CMSIS/core_cm7.h
rename to libs/stm32f4xx/inc/CMSIS/core_cm7.h
diff --git a/lib/inc/CMSIS/core_cmFunc.h b/libs/stm32f4xx/inc/CMSIS/core_cmFunc.h
similarity index 100%
rename from lib/inc/CMSIS/core_cmFunc.h
rename to libs/stm32f4xx/inc/CMSIS/core_cmFunc.h
diff --git a/lib/inc/CMSIS/core_cmInstr.h b/libs/stm32f4xx/inc/CMSIS/core_cmInstr.h
similarity index 100%
rename from lib/inc/CMSIS/core_cmInstr.h
rename to libs/stm32f4xx/inc/CMSIS/core_cmInstr.h
diff --git a/lib/inc/CMSIS/core_cmSimd.h b/libs/stm32f4xx/inc/CMSIS/core_cmSimd.h
similarity index 100%
rename from lib/inc/CMSIS/core_cmSimd.h
rename to libs/stm32f4xx/inc/CMSIS/core_cmSimd.h
diff --git a/lib/inc/CMSIS/core_sc000.h b/libs/stm32f4xx/inc/CMSIS/core_sc000.h
similarity index 100%
rename from lib/inc/CMSIS/core_sc000.h
rename to libs/stm32f4xx/inc/CMSIS/core_sc000.h
diff --git a/lib/inc/CMSIS/core_sc300.h b/libs/stm32f4xx/inc/CMSIS/core_sc300.h
similarity index 100%
rename from lib/inc/CMSIS/core_sc300.h
rename to libs/stm32f4xx/inc/CMSIS/core_sc300.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/Legacy/stm32_hal_legacy.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/Legacy/stm32_hal_legacy.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/Legacy/stm32_hal_legacy.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/Legacy/stm32_hal_legacy.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/misc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/misc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/misc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/misc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4x7_eth_conf.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4x7_eth_conf.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4x7_eth_conf.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4x7_eth_conf.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hal_conf.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hal_conf.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hal_conf.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hal_conf.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.h
diff --git a/lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.h b/libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.h
similarity index 100%
rename from lib/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.h
rename to libs/stm32f4xx/inc/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.h
diff --git a/lib/inc/stm32f4xx.h b/libs/stm32f4xx/inc/stm32f4xx.h
similarity index 100%
rename from lib/inc/stm32f4xx.h
rename to libs/stm32f4xx/inc/stm32f4xx.h
diff --git a/lib/inc/stm32f4xx_conf.h b/libs/stm32f4xx/inc/stm32f4xx_conf.h
similarity index 100%
rename from lib/inc/stm32f4xx_conf.h
rename to libs/stm32f4xx/inc/stm32f4xx_conf.h
diff --git a/lib/inc/system_stm32f4xx.h b/libs/stm32f4xx/inc/system_stm32f4xx.h
similarity index 100%
rename from lib/inc/system_stm32f4xx.h
rename to libs/stm32f4xx/inc/system_stm32f4xx.h
diff --git a/lib/src/STM32F439ZITx_FLASH.ld b/libs/stm32f4xx/src/STM32F439ZITx_FLASH.ld
similarity index 100%
rename from lib/src/STM32F439ZITx_FLASH.ld
rename to libs/stm32f4xx/src/STM32F439ZITx_FLASH.ld
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/misc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/misc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/misc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/misc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_adc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_can.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_crc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_aes.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_aes.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_aes.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_aes.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_des.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_des.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_des.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_des.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_tdes.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_tdes.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_tdes.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_cryp_tdes.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dac.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dbgmcu.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dcmi.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_dma.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_exti.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_flash.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_fsmc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_gpio.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_md5.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_md5.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_md5.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_md5.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_sha1.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_sha1.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_sha1.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_hash_sha1.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_i2c.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_iwdg.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_pwr.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rcc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rng.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_rtc.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_sdio.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_spi.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_syscfg.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_tim.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_usart.c
diff --git a/lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.c b/libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.c
similarity index 100%
rename from lib/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.c
rename to libs/stm32f4xx/src/STM32F4xx_StdPeriph_Driver/stm32f4xx_wwdg.c
diff --git a/lib/src/startup_stm32f439xx.S b/libs/stm32f4xx/src/startup_stm32f439xx.S
similarity index 100%
rename from lib/src/startup_stm32f439xx.S
rename to libs/stm32f4xx/src/startup_stm32f439xx.S
diff --git a/lib/src/startup_stm32f4xx.S b/libs/stm32f4xx/src/startup_stm32f4xx.S
similarity index 100%
rename from lib/src/startup_stm32f4xx.S
rename to libs/stm32f4xx/src/startup_stm32f4xx.S
diff --git a/lib/src/stm32_flash.ld b/libs/stm32f4xx/src/stm32_flash.ld
similarity index 100%
rename from lib/src/stm32_flash.ld
rename to libs/stm32f4xx/src/stm32_flash.ld
diff --git a/lib/src/stm32f439zi.ld b/libs/stm32f4xx/src/stm32f439zi.ld
similarity index 100%
rename from lib/src/stm32f439zi.ld
rename to libs/stm32f4xx/src/stm32f439zi.ld
diff --git a/lib/src/stm32f439zi_flash.ld b/libs/stm32f4xx/src/stm32f439zi_flash.ld
similarity index 100%
rename from lib/src/stm32f439zi_flash.ld
rename to libs/stm32f4xx/src/stm32f439zi_flash.ld
diff --git a/lib/src/system_stm32f4xx.c b/libs/stm32f4xx/src/system_stm32f4xx.c
similarity index 100%
rename from lib/src/system_stm32f4xx.c
rename to libs/stm32f4xx/src/system_stm32f4xx.c
diff --git a/nanopb b/nanopb
deleted file mode 160000
index 7f88274..0000000
--- a/nanopb
+++ /dev/null
@@ -1 +0,0 @@
-Subproject commit 7f88274070afa5edfaf608f4d8e32f3d3c1de139
diff --git a/toolchain-arm-none-eabi.cmake b/toolchain-arm-none-eabi.cmake
index c16d2c0..6853bd9 100644
--- a/toolchain-arm-none-eabi.cmake
+++ b/toolchain-arm-none-eabi.cmake
@@ -20,6 +20,5 @@ set(shared_options "-Wall -Wextra -O2 -mlittle-endian -mthumb -mcpu=cortex-m4 -m
 set(CMAKE_C_FLAGS_INIT "${shared_options}" CACHE INTERNAL "Initial options for C compiler.")
 set(CMAKE_CXX_FLAGS_INIT "${shared_options}" CACHE INTERNAL "Initial options for C++ compiler.")
 set(CMAKE_EXE_LINKER_FLAGS_INIT "-Wl,--gc-sections,--print-memory-usage,-Map=${PROJECT_BINARY_DIR}/${PROJECT_NAME}.map" CACHE INTERNAL "Initial options for executable linker.")
-# set(CMAKE_EXE_LINKER_FLAGS_INIT "${CMAKE_EXE_LINKER_FLAGS_INIT}, -T ${CMAKE_SOURCE_DIR}/lib/src/stm32f439zi_flash.ld")