diff --git a/.gitmodules b/.gitmodules
index 7bc6a2b..ac4a782 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -1,3 +1,6 @@
 [submodule "tinyusb"]
 	path = tinyusb
 	url = https://github.com/hathach/tinyusb
+[submodule "CMSIS_5"]
+	path = CMSIS_5
+	url = https://github.com/ARM-software/CMSIS_5.git
diff --git a/CMSIS_5 b/CMSIS_5
new file mode 160000
index 0000000..d61cf40
--- /dev/null
+++ b/CMSIS_5
@@ -0,0 +1 @@
+Subproject commit d61cf40e6c44726917d9085660f7eb2691547cc7
diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb243d0..f3f0d5f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,18 +21,18 @@ if(FAMILY STREQUAL "rp2040")
   target_sources(${PROJECT} PUBLIC
     ${CMAKE_CURRENT_SOURCE_DIR}/main.c
     ${CMAKE_CURRENT_SOURCE_DIR}/usb_descriptors.c
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP.c
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/JTAG_DP.c
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP_vendor.c
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/SWO.c
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/SW_DP.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Source/JTAG_DP.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP_vendor.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Source/SWO.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Source/SW_DP.c
   )
 
  # Example include
   target_include_directories(${PROJECT} PUBLIC
     ${CMAKE_CURRENT_SOURCE_DIR}/
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Include/
-    ${TOP}/lib/CMSIS_5/CMSIS/Core/Include/
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/DAP/Firmware/Include/
+    ${CMAKE_CURRENT_SOURCE_DIR}/CMSIS_5/CMSIS/Core/Include/
     ${CMAKE_CURRENT_SOURCE_DIR}/bsp/${FAMILY}/
     ${CMAKE_CURRENT_SOURCE_DIR}/bsp/default/
   )
diff --git a/Makefile b/Makefile
index ed0c6ff..f25f225 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@ include ./tinyusb/examples/make.mk
 
 INC += \
 	. \
-	$(TOP)/lib/CMSIS_5/CMSIS/DAP/Firmware/Include \
+	./CMSIS_5/CMSIS/DAP/Firmware/Include \
 	./bsp/$(BOARD) \
 	./bsp/default \
 	$(TOP)/hw
@@ -13,10 +13,10 @@ APP_SOURCE += $(wildcard ./*.c)
 SRC_C += $(addprefix $(CURRENT_PATH)/, $(APP_SOURCE))
 
 SRC_C += \
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP.c \
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/JTAG_DP.c \
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/DAP_vendor.c \
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/SWO.c \
-    ${TOP}/lib/CMSIS_5/CMSIS/DAP/Firmware/Source/SW_DP.c
+    ./CMSIS_5/CMSIS/DAP/Firmware/Source/DAP.c \
+    ./CMSIS_5/CMSIS/DAP/Firmware/Source/JTAG_DP.c \
+    ./CMSIS_5/CMSIS/DAP/Firmware/Source/DAP_vendor.c \
+    ./CMSIS_5/CMSIS/DAP/Firmware/Source/SWO.c \
+    ./CMSIS_5/CMSIS/DAP/Firmware/Source/SW_DP.c
 
 include ./tinyusb/examples/rules.mk
diff --git a/README.md b/README.md
index dd9a851..f89317b 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@ Whereas the original code used ST's STM32 USB drivers, this new iteration uses [
 
 ## Building
 
-After initially downloading this project's code, issue the following command to download TinyUSB code and its submodules (including ARM's CMSIS_5):
+After initially downloading this project's code, issue the following command to download TinyUSB and CMSIS_5 code (as well as all submodules):
 
 ```
 git submodule update --init --recursive