diff --git a/.github/workflows/build_aarch64.yml b/.github/workflows/build_aarch64.yml
new file mode 100644
index 000000000..0cc7a5de1
--- /dev/null
+++ b/.github/workflows/build_aarch64.yml
@@ -0,0 +1,67 @@
+name: Build AArch64
+
+on:
+  pull_request:
+  push:
+  release:
+    types:
+      - created
+
+jobs:
+  # ---------------------------------------
+  # Build AARCH64 family
+  # ---------------------------------------
+  build-arm:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        family:
+        # Alphabetical order
+        - 'raspberrypi4'
+    steps:
+    - name: Setup Python
+      uses: actions/setup-python@v2
+
+    - name: Checkout TinyUSB
+      uses: actions/checkout@v2
+
+    - name: Checkout common submodules in lib
+      run: git submodule update --init lib/FreeRTOS-Kernel lib/lwip lib/sct_neopixel
+
+    - name: Checkout hathach/linkermap
+      uses: actions/checkout@v2
+      with:
+         repository: hathach/linkermap
+         path: linkermap
+
+    - name: Set Toolchain URL
+      run: echo >> $GITHUB_ENV TOOLCHAIN_URL=https://developer.arm.com/-/media/Files/downloads/gnu-a/10.3-2021.07/binrel/gcc-arm-10.3-2021.07-x86_64-aarch64-none-elf.tar.xz
+
+    - name: Cache Toolchain
+      uses: actions/cache@v2
+      id: cache-toolchain
+      with:
+        path: ~/cache/
+        key: ${{ runner.os }}-21-11-02-${{ env.TOOLCHAIN_URL }}
+
+    - name: Install Toolchain
+      if: steps.cache-toolchain.outputs.cache-hit != 'true'
+      run: |
+        mkdir -p ~/cache/toolchain
+        wget --progress=dot:mega $TOOLCHAIN_URL -O toolchain.tar.gz
+        tar -C ~/cache/toolchain -xaf toolchain.tar.gz
+
+    - name: Set Toolchain Path
+      run: echo >> $GITHUB_PATH `echo ~/cache/toolchain/*/bin`
+
+    - name: Build
+      run: python3 tools/build_family.py ${{ matrix.family }}
+
+    - name: Linker Map
+      run: |
+        pip install linkermap/
+        for ex in `ls -d examples/device/*/`; do \
+          find ${ex} -name *.map -print -quit | \
+          xargs -I % sh -c 'echo "::group::%"; linkermap -v %; echo "::endgroup::"'; \
+        done
diff --git a/.github/workflows/build.yml b/.github/workflows/build_arm.yml
similarity index 100%
rename from .github/workflows/build.yml
rename to .github/workflows/build_arm.yml
diff --git a/.gitmodules b/.gitmodules
index 79dec144e..a95e64ee6 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -130,3 +130,4 @@
 [submodule "hw/mcu/broadcom"]
 	path = hw/mcu/broadcom
 	url = https://github.com/adafruit/broadcom-peripherals.git
+	branch = main-build
diff --git a/examples/device/audio_4_channel_mic/src/main.c b/examples/device/audio_4_channel_mic/src/main.c
index 983b87e5b..d085dd43a 100644
--- a/examples/device/audio_4_channel_mic/src/main.c
+++ b/examples/device/audio_4_channel_mic/src/main.c
@@ -141,7 +141,7 @@ void tud_resume_cb(void)
 void audio_task(void)
 {
   // Yet to be filled - e.g. put meas data into TX FIFOs etc.
-  asm("nop");
+  // asm("nop");
 }
 
 //--------------------------------------------------------------------+
diff --git a/examples/device/audio_test/src/main.c b/examples/device/audio_test/src/main.c
index 9a2fdd3a1..ed13ce993 100644
--- a/examples/device/audio_test/src/main.c
+++ b/examples/device/audio_test/src/main.c
@@ -142,7 +142,7 @@ void tud_resume_cb(void)
 void audio_task(void)
 {
   // Yet to be filled - e.g. put meas data into TX FIFOs etc.
-  asm("nop");
+  // asm("nop");
 }
 
 //--------------------------------------------------------------------+
diff --git a/examples/device/cdc_msc_freertos/.skip.MCU_BCM2711 b/examples/device/cdc_msc_freertos/.skip.MCU_BCM2711
new file mode 100644
index 000000000..e69de29bb
diff --git a/examples/device/hid_composite_freertos/.skip.MCU_BCM2711 b/examples/device/hid_composite_freertos/.skip.MCU_BCM2711
new file mode 100644
index 000000000..e69de29bb
diff --git a/hw/bsp/raspberrypi4/family.mk b/hw/bsp/raspberrypi4/family.mk
index b1d14a6ec..2e61b9e74 100644
--- a/hw/bsp/raspberrypi4/family.mk
+++ b/hw/bsp/raspberrypi4/family.mk
@@ -1,9 +1,8 @@
-UF2_FAMILY_ID = 0x57755a57
+MCU_DIR = hw/mcu/broadcom
+DEPS_SUBMODULES += $(MCU_DIR)
 
 include $(TOP)/$(BOARD_PATH)/board.mk
 
-MCU_DIR = hw/mcu/broadcom
-
 CC = clang
 
 CFLAGS += \