diff --git a/.vscode/c_cpp_properties.json b/.vscode/c_cpp_properties.json
new file mode 100644
index 0000000..eda337c
--- /dev/null
+++ b/.vscode/c_cpp_properties.json
@@ -0,0 +1,18 @@
+{
+    "configurations": [
+        {
+            "name": "Linux",
+            "includePath": [
+                "${workspaceFolder}/**"
+            ],
+            // "defines": ["DO_UNIT_TESTS=1"],
+            "compilerPath": "/usr/bin/clang",
+            "cStandard": "c17",
+            "cppStandard": "c++17",
+            "intelliSenseMode": "linux-clang-x64",
+            "configurationProvider": "ms-vscode.cmake-tools",
+            "compileCommands": "${workspaceFolder}/build/compile_commands.json"
+        }
+    ],
+    "version": 4
+}
\ No newline at end of file
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 660b946..a5aeafb 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -13,6 +13,11 @@
     "fifo_type.h": "c",
     "chrono": "c",
     "span": "c",
-    "worker.h": "c"
+    "worker.h": "c",
+    "fifo.h": "c",
+    "string.h": "c",
+    "*.ipp": "c",
+    "cstring": "c",
+    "stddef.h": "c"
   }
 }
\ No newline at end of file
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0b98859..3f7bd4f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,6 +7,7 @@ project(${PROJECT_NAME} LANGUAGES C)
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED ON)
 set(CMAKE_C_EXTENSIONS OFF)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 add_executable(${PROJECT_NAME} ${SOURCE_DIR}/main.c)
 
@@ -29,8 +30,7 @@ set(SOURCES
 )
 
 target_include_directories(${PROJECT_NAME} PRIVATE ${HEADERS})
-# target_compile_definitions(${PROJECT_NAME} PRIVATE __USE_POSIX199309 __USE_ISOC11)
-target_compile_definitions(${PROJECT_NAME} PRIVATE _POSIX_C_SOURCE=199309L _ISOC11_SOURCE)
+# target_compile_definitions(${PROJECT_NAME} PUBLIC )
 
 target_sources(${PROJECT_NAME} PRIVATE ${SOURCES})
 
diff --git a/readme.md b/readme.md
index 6f6dd6c..cc59c5a 100644
--- a/readme.md
+++ b/readme.md
@@ -68,6 +68,19 @@ FIFO пуст или FIFO полон. Вся логика работы прог
 
 
 ## Функции и их параметры
+### worker
+- *int WORK_execute(int (*callback)(workerHost_s*), workerHost_s *worker);*
+- int WORK_preparePackage(workerHost_s *worker);
+- int WORK_sendPackage(workerHost_s *worker);
+- int WORK_waitPackage(workerHost_s *worker);
+- int WORK_receivePackage(workerHost_s *worker);
+- int WORK_checkPackage(workerHost_s *worker);
+- int WORK_parsePackage(workerHost_s *worker);
+- int WORK_fillBuffer8b(uint8_t *buffer, size_t size);
+
+// tools
+int WORK_printBlocks(workerHost_s *worker, uint8_t mode);
+int WORK_testFill(uint8_t* buffer, size_t bufferSize);
 ### tools
 - TOOL_workerPrintBlocks
   - hdlcHost_s *worker - указатель на машину
diff --git a/src/fifo/fifo.c b/src/fifo/fifo.c
index 8eb42d8..255b712 100644
--- a/src/fifo/fifo.c
+++ b/src/fifo/fifo.c
@@ -1,2 +1,90 @@
 #include "fifo.h"
+#include "stdio.h"
 
+// if (FIFO_get(fifo, byte) == 0) {
+//   OK
+// } else {
+//   FIFO ERROR
+// }
+
+int FIFO_isUsable(fifo_s* fifo);
+
+// Инициализация fifo
+int FIFO_init(fifo_s* fifo) {
+  if (fifo != NULL) {
+    for (size_t i = 0; i < FIFO_DATA_SIZE; ++i) {
+      fifo->data[i] = 0;
+    }
+    fifo->head = 0;
+    fifo->state = FIFOS_empty;
+    fifo->isInitialized = 1;
+    if (FIFO_isUsable(fifo) == 0) {
+      return 0;
+    }
+  }
+  return -1;
+}
+
+
+// Заполнение fifo
+int FIFO_put(fifo_s* fifo, uint8_t data) {
+  if (FIFO_isUsable(fifo) == 0) {  // Не заполнено
+    if ((fifo->state == FIFOS_empty) || (fifo->state == FIFOS_ready)) {
+      fifo->data[fifo->head] = data;
+
+      if (fifo->head < FIFO_DATA_SIZE-1) {
+        fifo->head++;
+        fifo->state = FIFOS_ready;
+      } else {
+        fifo->head = FIFO_DATA_SIZE-1; 
+        fifo->state = FIFOS_full; 
+      }
+      return 0;
+    }
+  }
+  return -1;
+}
+
+
+// Получение из fifo
+int FIFO_get(fifo_s* fifo, uint8_t *data) {
+  if (FIFO_isUsable(fifo) == 0) {
+    if ((fifo->state == FIFOS_full) || (fifo->state == FIFOS_ready)) {
+      *data = fifo->data[fifo->head-1];
+      fifo->data[fifo->head-1] = 0;
+      if (fifo->head > 1) {
+        fifo->head--;
+        fifo->state = FIFOS_ready;
+      } else {
+        fifo->head = 0;  
+        fifo->state = FIFOS_empty;
+      }
+      return 0;
+    }
+  }
+  return -1;
+}
+
+
+int FIFO_print(fifo_s* fifo) {
+  if (FIFO_isUsable(fifo) == 0) {
+    printf("FIFO: ");
+    for (size_t i = 0; i < FIFO_DATA_SIZE; i++) {
+      printf("%d", fifo->data[i]);
+    }
+    printf("\n");
+    return 0;
+  }
+  return -1;
+}
+
+
+// Проверка доступности fifo
+int FIFO_isUsable(fifo_s* fifo) {
+  if (fifo != NULL) {
+    if (fifo->isInitialized == 1) {
+      return 0;
+    }
+  }
+  return -1;
+}
\ No newline at end of file
diff --git a/src/fifo/fifo.h b/src/fifo/fifo.h
index 2684fa9..d3a038d 100644
--- a/src/fifo/fifo.h
+++ b/src/fifo/fifo.h
@@ -3,6 +3,25 @@
 #define FIFO_H
 
 #include "fifo_type.h"
+#include <stddef.h>
 
+// Размер FIFO
+#define FIFO_DATA_SIZE 8
+
+// Структура FIFO
+typedef struct {
+  uint8_t data[FIFO_DATA_SIZE];
+  uint8_t head;
+  fifoState_e state;
+  uint8_t isInitialized;
+} fifo_s;
+
+
+// Функции FIFO
+int FIFO_init(fifo_s* fifo);
+int FIFO_put(fifo_s* fifo, uint8_t data);
+int FIFO_get(fifo_s* fifo, uint8_t *data);
+int FIFO_print(fifo_s* fifo);
+int FIFO_isUsable(fifo_s* fifo);
 
 #endif // FIFO_H
\ No newline at end of file
diff --git a/src/fifo/fifo_type.h b/src/fifo/fifo_type.h
index fa14505..b2b826b 100644
--- a/src/fifo/fifo_type.h
+++ b/src/fifo/fifo_type.h
@@ -10,13 +10,7 @@ typedef enum {
   FIFOS_ready,
   FIFOS_full,
   FIFOS_error
-} fifoState;
+} fifoState_e;
 
-// Структура FIFO
-typedef struct {
-  uint8_t data[8];
-  uint8_t pointer;
-  fifoState state;
-} fifo_s;
 
 #endif // FIFO_TYPE_H
\ No newline at end of file
diff --git a/src/main.c b/src/main.c
index abe03a4..ece7f28 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,12 +1,5 @@
 #include "main.h"
 
-#if __cplusplus
-#pragma message ("plus")
-#else
-#pragma message ("pure")
-#endif
-
-
 // Перечисление статусов машины состояния
 enum bigLoopOsState_e {
   OS_first = 0,
diff --git a/src/main.h b/src/main.h
index 45cd698..a0e4fa5 100644
--- a/src/main.h
+++ b/src/main.h
@@ -2,6 +2,8 @@
 #ifndef MAIN_H
 #define MAIN_H
 
+#define DO_UNIT_TESTS 1
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
diff --git a/src/tools.c b/src/tools.c
index 44d4eab..e3d8d17 100644
--- a/src/tools.c
+++ b/src/tools.c
@@ -1,8 +1,18 @@
 // Файл с общими функциями и конфигурацией
 
-#include "main.h"
+#define _POSIX_C_SOURCE 199309L
 #include <time.h>
 
+#if __cplusplus
+#pragma message ("plus")
+#else
+#pragma message ("pure")
+#endif
+
+#include "main.h"
+
+
+
 
 // Вычисление контрольной суммы CRC16
 uint16_t CRC16_compute(uint8_t *data, size_t length) {
@@ -53,12 +63,12 @@ uint16_t TOOL_reverseBitsN(uint16_t value, uint8_t n) {
 
 
 void TOOL_msleep(long milliseconds) {
-    struct timespec ts;
-    ts.tv_sec = milliseconds / 1000; // Seconds part
-    ts.tv_nsec = (milliseconds % 1000) * 1000000; // Nanoseconds part
+    struct timespec time;
+    time.tv_sec = milliseconds / 1000;
+    time.tv_nsec = (milliseconds % 1000) * 1000000;
 
     // nanosleep can be interrupted by signals, so we loop if interrupted
-    while (nanosleep(&ts, &ts) == -1) {
+    while (nanosleep(&time, &time) == -1) {
         // If interrupted, remaining time is in ts, so we continue sleeping
         // unless an actual error occurred (other than EINTR)
         // For simplicity, this example assumes EINTR is the only -1 cause.
diff --git a/src/worker/worker.c b/src/worker/worker.c
index 3cb5ec1..09a36d2 100644
--- a/src/worker/worker.c
+++ b/src/worker/worker.c
@@ -29,15 +29,24 @@ int WORK_sendPackage(workerHost_s *worker)  {
 // Ожидание пакета
 int WORK_waitPackage(workerHost_s *worker) {
   printf("WORKX: .. Waiting for a package\n");
-  return 0;
+  if (FIFO_isUsable(worker->fifo) == 0) {
+    return 0;
+  }
+  return -1;
 }
 
 
 int WORK_receivePackage(workerHost_s *worker) {
   printf("WORKX: .. Receiving package\n");
   // Receiving in buffer
+  uint8_t buf;
+  if (FIFO_get(worker->fifo, &buf) == 0) {
+    // return 0;
+  }
+  
+  return -1;
 
-  WORK_testFill(worker->byteBuffer, WORK_BYTE_BUFFER_SIZE);
+  if (DO_UNIT_TESTS){WORK_testFill(worker->byteBuffer, WORK_BYTE_BUFFER_SIZE);}
   
   return 0;
 }
diff --git a/src/worker/worker.h b/src/worker/worker.h
index 263ff6e..b714d86 100644
--- a/src/worker/worker.h
+++ b/src/worker/worker.h
@@ -10,7 +10,7 @@
 
 #include "hdlc_type.h"
 
-#include "fifo_type.h"
+#include "fifo.h"
 
 // Структура устройства
 typedef struct {
@@ -33,9 +33,11 @@ int WORK_parsePackage(workerHost_s *worker);
 
 int WORK_fillBuffer8b(uint8_t *buffer, size_t size);
 
-// tools
+// toolsNtests
 int WORK_printBlocks(workerHost_s *worker, uint8_t mode);
 int WORK_testFill(uint8_t* buffer, size_t bufferSize);
+int WORK_testFifo(fifo_s *fifo);
+
 
 #endif //WORKER_H
 
diff --git a/src/worker/worker_master.c b/src/worker/worker_master.c
index abc888f..3bd8ec6 100644
--- a/src/worker/worker_master.c
+++ b/src/worker/worker_master.c
@@ -16,6 +16,10 @@ workerHost_s* WORK_masterInit () {
     hdlcMaster.fifo = &hdlcMasterFifo;
     hdlcMaster.isInitialized = true;
     hdlcMaster.byteBuffer = masterBuffer;
+    FIFO_init(&hdlcMasterFifo);
+
+    if (DO_UNIT_TESTS){WORK_testFifo(hdlcMaster.fifo);} 
+
     printf("WMAST: Master initialization done\n");
     WORK_printBlocks(&hdlcMaster, 3);
     
diff --git a/src/worker/worker_tools.c b/src/worker/worker_tools.c
index 435751c..de456da 100644
--- a/src/worker/worker_tools.c
+++ b/src/worker/worker_tools.c
@@ -32,7 +32,7 @@ int WORK_printBlocks(workerHost_s *worker, uint8_t mode) {
     }
     printf("\n");
 
-    printf("TOOL: .. Pointer: %d ", worker->fifo->pointer);
+    printf("TOOL: .. Pointer: %d ", worker->fifo->head);
   }
 
   return 0;
@@ -57,6 +57,24 @@ int WORK_testFill(uint8_t* buffer, size_t bufferSize) {
 }
 
 
+int WORK_testFifo(fifo_s *fifo) {
+  printf("TEST: FIFO START:\n");
+    
+  FIFO_put(fifo, 4);
+  FIFO_put(fifo, 3);
+  FIFO_put(fifo, 8);
+  FIFO_print(fifo);
+  uint8_t arr[10] = {0};
+  for (int a = 0; a < 10; a++) {
+    FIFO_get(fifo, &arr[a]);
+    printf("%d:", arr[a]);
+  }
+  printf("\n");
+
+  printf("TEST: FIFO END:\n");
+}
+
+
 // Заполнение массива
 int WORK_fillBuffer8b(uint8_t *buffer, size_t size) {
   memset(buffer, 0, size);