diff --git a/.github/.gitignore b/.github/.gitignore
deleted file mode 100644
index 8b13789..0000000
--- a/.github/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/.github/actions/avr_setup/action.yml b/.github/actions/avr_setup/action.yml
new file mode 100644
index 0000000..3b92db0
--- /dev/null
+++ b/.github/actions/avr_setup/action.yml
@@ -0,0 +1,18 @@
+name: "Get changed files list"
+description: "Setup Node with caching for dependencies"
+runs:
+  using: "composite"
+  steps:
+    - name: Set up Arduino CLI
+      uses: arduino/setup-arduino-cli@v2
+
+    - name: Install platform
+      run: |
+        arduino-cli core update-index
+        arduino-cli core install ${{ env.platform }}
+      shell: bash
+
+    - name: Install popular libs
+      run: |
+        arduino-cli lib install LiquidCrystal
+      shell: bash
\ No newline at end of file
diff --git a/.github/actions/get_changed_files/action.yml b/.github/actions/get_changed_files/action.yml
new file mode 100644
index 0000000..ecf73ac
--- /dev/null
+++ b/.github/actions/get_changed_files/action.yml
@@ -0,0 +1,13 @@
+name: "Get changed files list"
+description: "Setup Node with caching for dependencies"
+runs:
+  using: "composite"
+  steps:
+    - name: Get changed files list
+      id: get_changed_files
+      run: |
+        echo "Changed files:"
+        git diff --name-only ${{ github.event.pull_request.base.sha }} > changed_files.txt
+        cat changed_files.txt
+        echo "The list is saved to changed_files.txt"
+      shell: bash
\ No newline at end of file
diff --git a/.github/workflows/Lab_01_CI.yml b/.github/workflows/Lab_01_CI.yml
deleted file mode 100644
index 985573b..0000000
--- a/.github/workflows/Lab_01_CI.yml
+++ /dev/null
@@ -1,37 +0,0 @@
-name: Cheking of compile Arduino sketch for AVR/AtMega and ESP8266
-
-on:
-  push:
-    branches: [ main, master ]
-  pull_request:
-    branches: [ main, master ]
-
-jobs:
-  test-matrix:
-    strategy:
-      matrix:
-        arduino-platform:
-          - "arduino:avr"
-          - "esp8266:esp8266"
-        include:
-          - arduino-platform: "arduino:avr"
-            fqbn: "arduino:avr:mega"
-          - arduino-platform: "esp8266:esp8266"
-            fqbn: "esp8266:esp8266:generic"
-
-    runs-on: ubuntu-22.04
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v4
-
-      - name: Set up Arduino CLI
-        uses: arduino/setup-arduino-cli@v2
-
-      - name: Install platform
-        run: |
-          arduino-cli core update-index
-          arduino-cli core install ${{ matrix.arduino-platform }}
-
-      - name: Compile Sketch
-        run: arduino-cli compile --fqbn ${{ matrix.fqbn }} ./mc_labs/mc_lab_01/*.ino
diff --git a/.github/workflows/lab-validation.yml b/.github/workflows/lab-validation.yml
new file mode 100644
index 0000000..059343b
--- /dev/null
+++ b/.github/workflows/lab-validation.yml
@@ -0,0 +1,114 @@
+name: Cheking of compile Arduino sketch for AVR/AtMega
+
+on:
+  pull_request:
+    branches: [main, master]
+
+env:
+  platform: "arduino:avr"
+  fqbn_master: "arduino:avr:mega"
+  COMMIT_COUNT: $(( ${{ github.event_name == 'pull_request' && github.event.pull_request.commits || 0 }} + 1 ))
+
+jobs:
+  handle_bad_branch_name:
+    runs-on: ubuntu-22.04
+    if: (contains(github.head_ref, 'mc_lab_1') || contains(github.head_ref, 'mc_lab_2') || contains(github.head_ref, 'mc_lab_3') || contains(github.head_ref, 'mc_lab_4') || contains(github.head_ref, 'mc_lab_5') || contains(github.head_ref, 'mc_lab_6') || contains(github.head_ref, 'mc_lab_7')) == false
+    steps:
+      - name: Fail the build
+        run: | 
+          echo "The branch name is not correct. It should contain 'mc_lab_' prefix"
+          exit 1
+  build_labs_1_to_4:
+    runs-on: ubuntu-22.04
+    if: contains(github.head_ref, 'mc_lab_1') || contains(github.head_ref, 'mc_lab_2') || contains(github.head_ref, 'mc_lab_3') || contains(github.head_ref, 'mc_lab_4')
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: ${{ env.COMMIT_COUNT }}
+
+      - name: Get changed files list
+        uses: ./.github/actions/get_changed_files
+
+      - name: Set up Arduino CLI
+        uses: ./.github/actions/avr_setup
+
+      - name: Compile Sketch
+        run: arduino-cli compile --fqbn ${{ env.fqbn_master }} $(grep -E '\.ino$' changed_files.txt | xargs)
+  build_lab_5:
+    runs-on: ubuntu-22.04
+    if: contains(github.head_ref, 'mc_lab_5')
+    env:
+      fqbn_slave: "arduino:avr:nano"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: ${{ env.COMMIT_COUNT }}
+
+      - name: Get changed files list
+        uses: ./.github/actions/get_changed_files
+
+      - name: Get master folder
+        run: |
+          cat changed_files.txt | xargs dirname | grep 'master' | grep -m 1 -vE '/(.*master.*|.*slave.*)/'  > master_project.txt
+          echo "Master project:"
+          cat master_project.txt
+
+      - name: Get slave folders
+        run: |
+          cat changed_files.txt | xargs dirname | grep 'slave' | grep -vE '/(.*master.*|.*slave.*)/'  > slave_projects.txt
+          echo "Slave projects:"
+          cat slave_projects.txt
+
+      - name: Check if there is at least one master and one slave project
+        run: |
+          if [ ! -s master_project.txt ] || [ ! -s slave_projects.txt ]; then
+            echo "There is no master or slave project"
+            exit 1
+          fi
+
+      - name: Set up Arduino CLI
+        uses: ./.github/actions/avr_setup
+
+      - name: Compile master
+        run: while read master_folder; do arduino-cli compile --fqbn ${{ env.fqbn_master }} $master_folder/*.ino; done < master_project.txt
+
+      - name: Compile slaves
+        run: while read slave_folder; do arduino-cli compile --fqbn ${{ env.fqbn_slave }} $slave_folder/*.ino; done < slave_projects.txt
+  build_lab_6:
+    runs-on: ubuntu-22.04
+    if: contains(github.head_ref, 'mc_lab_6')
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: ${{ env.COMMIT_COUNT }}
+
+      - name: It just passes
+        run: echo "It just passes. It's too complex"
+  build_lab_7:
+    runs-on: ubuntu-22.04
+    if: contains(github.head_ref, 'mc_lab_7')
+    env:
+      register-bindings: "m2560def.inc"
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: ${{ env.COMMIT_COUNT }}
+
+      - name: Get changed files list
+        uses: ./.github/actions/get_changed_files
+
+      - name: Setup AVRA Assembler
+        run: |
+          git clone https://github.com/Ro5bert/avra.git
+          cd avra
+          sudo make install
+
+      - name: Preprocess sketch - append register bindings to the top of the file
+        run: printf ".include \"${{ env.register-bindings }}\"\n\n" | cat - $(grep -m 1 -E '\.(asm|S)$' changed_files.txt | xargs) > pipeline_main_assembly_source_file.asm
+
+      - name: Compile Sketch
+        run: avra pipeline_main_assembly_source_file.asm
diff --git a/mc_labs/mc_lab_02/lab2-mko/lab2-mko.ino b/mc_labs/mc_lab_02/lab2-mko/lab2-mko.ino
new file mode 100644
index 0000000..be37762
--- /dev/null
+++ b/mc_labs/mc_lab_02/lab2-mko/lab2-mko.ino
@@ -0,0 +1,74 @@
+const unsigned char BUTTON_0_PIN = 49;
+const unsigned char BUTTON_1_PIN = 47;
+
+const unsigned char LED_PINS[] = { 62, 63, 64, 65, 66, 67, 68, 69 };
+const unsigned int DELAY = 800;
+
+void setup() {
+  for (int i = 0; i < 8; i++) {
+    pinMode(LED_PINS[i], OUTPUT);
+    digitalWrite(LED_PINS[i], LOW);
+  }
+
+  pinMode(BUTTON_0_PIN, INPUT);
+  digitalWrite(BUTTON_0_PIN, HIGH);
+
+  pinMode(BUTTON_1_PIN, INPUT);
+  digitalWrite(BUTTON_1_PIN, HIGH);
+
+  Serial.begin(9600);
+}
+
+
+unsigned char currentIteration = 0;
+unsigned char currentMode = 0;
+void bleep_sequential() {
+  digitalWrite(LED_PINS[currentIteration], HIGH);
+  delay(DELAY);
+  digitalWrite(LED_PINS[currentIteration], LOW);
+  currentIteration = (currentIteration + 1) % 8;
+}
+
+void bleep_two_converge() {
+  digitalWrite(LED_PINS[currentIteration], HIGH);
+  digitalWrite(LED_PINS[7 - currentIteration], HIGH);
+  delay(DELAY);
+  digitalWrite(LED_PINS[currentIteration], LOW);
+  digitalWrite(LED_PINS[7 - currentIteration], LOW);
+  currentIteration = (currentIteration + 1) % 4;
+}
+
+
+
+void loop() {
+  int inByte = -1;
+  if (Serial.available())
+    inByte = Serial.read();
+
+  if (currentMode == 0) {
+    if (inByte == 0xA1)
+      currentMode = 1;
+    else if (inByte == 0xB1)
+      currentMode = 2;
+  }
+
+  if (currentMode == 1)
+    bleep_sequential();
+  else if (currentMode == 2)
+    bleep_two_converge();
+
+  if (currentIteration == 0)
+    currentMode = 0;
+
+
+  if (digitalRead(BUTTON_0_PIN) == LOW)
+  {
+    Serial.write(0xA1);
+    delay(1000);
+  }
+  if (digitalRead(BUTTON_1_PIN) == LOW)
+  {
+    Serial.write(0xB1);
+    delay(1000);
+  }
+}
diff --git a/mc_labs/mc_lab_02/lab2-mko/lab2.pdsprj b/mc_labs/mc_lab_02/lab2-mko/lab2.pdsprj
new file mode 100644
index 0000000..de5e2e8
Binary files /dev/null and b/mc_labs/mc_lab_02/lab2-mko/lab2.pdsprj differ