diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 1b4947a..505aafd 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -10,9 +10,9 @@ jobs:
         EXTRA_PACKAGES:
         TRIZEN_EXTRA_PACKAGES:
 
-      name: docker
+      name: build
       steps:
-        - name: checkout repo
+        - name: Checkout repo
           uses: actions/checkout@v3
           with:
             submodules: 'recursive'
@@ -23,7 +23,7 @@ jobs:
         - name: Run Docker
           run: docker run -v ./:/project kvasir_fw_build
 
-        - name: upload firmware
+        - name: Upload firmware
           uses: actions/upload-artifact@v3
           with:
             name: firmware
@@ -34,3 +34,30 @@ jobs:
               docker_build/*.uf2
               docker_build/*.lst
               docker_build/*.map
+
+    test-on-wokwi:
+
+      runs-on: ubuntu-latest
+
+      needs: build
+
+      name: test
+      steps:
+        - name: Checkout repo
+          uses: actions/checkout@v3
+          with:
+            submodules: 'recursive'
+
+        - name: Download firmware
+          uses: actions/download-artifact@v2
+          with:
+            name: firmware
+            path: build
+
+        - name: Test the binary on Wokwi
+          uses: wokwi/wokwi-ci-action@v1
+          with:
+            token: ${{ secrets.WOKWI_CLI_TOKEN }}
+            path: /
+            timeout: 1000 # ms
+            scenario: 'blink.test.yaml'
diff --git a/blink.test.yaml b/blink.test.yaml
new file mode 100644
index 0000000..3f008df
--- /dev/null
+++ b/blink.test.yaml
@@ -0,0 +1,15 @@
+name: Blinky test
+version: 1
+author: Dominic Poeschko
+
+steps:
+  - wait-serial: 'LED on'
+  - expect-pin:
+      part-id: led1
+      pin: A
+      value: 1
+  - wait-serial: 'LED off'
+  - expect-pin:
+      part-id: led1
+      pin: A
+      value: 0
diff --git a/diagram.json b/diagram.json
new file mode 100644
index 0000000..d9f7db3
--- /dev/null
+++ b/diagram.json
@@ -0,0 +1,30 @@
+{
+  "version": 1,
+  "author": "Dominic Poeschko",
+  "editor": "wokwi",
+  "parts": [
+    {
+      "type": "wokwi-pi-pico",
+      "id": "pico",
+      "top": 73.9,
+      "left": 132.55,
+      "rotate": 90,
+      "attrs": { "env": "arduino-community" }
+    },
+    {
+      "type": "wokwi-resistor",
+      "id": "r1",
+      "top": 86,
+      "left": 172.8,
+      "attrs": { "value": "1000" }
+    },
+    { "type": "wokwi-led", "id": "led1", "top": 54, "left": 138.2, "attrs": { "color": "red" } }
+  ],
+  "connections": [
+    [ "pico:GP0", "$serialMonitor:RX", "", [] ],
+    [ "pico:GP1", "$serialMonitor:TX", "", [] ],
+    [ "pico:GP2", "r1:2", "green", [ "v0" ] ],
+    [ "r1:1", "led1:A", "green", [ "v0" ] ],
+    [ "pico:GND.3", "led1:C", "black", [ "v-19.2", "h9.6" ] ]
+  ]
+}
diff --git a/src/ApplicationConfig.hpp b/src/ApplicationConfig.hpp
index 7daf013..709aeda 100644
--- a/src/ApplicationConfig.hpp
+++ b/src/ApplicationConfig.hpp
@@ -10,5 +10,22 @@ using Clock          = HW::SystickClock;
 using StackProtector = Kvasir::StackProtector<>;
 using FaultHandler   = Kvasir::Fault::Handler<HW::Fault_CleanUpAction>;
 
-using Startup = Kvasir::Startup::
-  Startup<HW::ClockSettings, Clock, HW::ComBackend, FaultHandler, StackProtector, HW::PinConfig>;
+struct DmaConfig {
+    static constexpr auto numberOfChannels     = 1;
+    static constexpr auto callbackFunctionSize = 8;
+};
+
+using Dma = Kvasir::DMA::DmaBase<DmaConfig>;
+
+using Uart
+  = Kvasir::UART::UartBehavior<HW::UartConfig, Dma, Dma::Channel::ch0, Dma::Priority::low, 512>;
+
+using Startup = Kvasir::Startup::Startup<
+  HW::ClockSettings,
+  Clock,
+  HW::ComBackend,
+  FaultHandler,
+  StackProtector,
+  HW::PinConfig,
+  Dma,
+  Uart>;
diff --git a/src/HWConfig.hpp b/src/HWConfig.hpp
index 95e26ad..73a03bd 100644
--- a/src/HWConfig.hpp
+++ b/src/HWConfig.hpp
@@ -2,13 +2,29 @@
 #include "HWConfigCommon.hpp"
 namespace HW {
 namespace Pin {
-    using led = decltype(makePinLocation(Kvasir::Io::port0, Kvasir::Io::pin25));
+
+    using uart_tx = decltype(makePinLocation(Kvasir::Io::port0, Kvasir::Io::pin0));
+    using uart_rx = decltype(makePinLocation(Kvasir::Io::port0, Kvasir::Io::pin1));
+    using led = decltype(makePinLocation(Kvasir::Io::port0, Kvasir::Io::pin2));
 }   // namespace Pin
 
 struct Fault_CleanUpAction {
     void operator()() {}
 };
 
+struct UartConfig {
+    static constexpr auto clockSpeed = ClockSpeed;
+
+    static constexpr auto instance      = 0;
+    static constexpr auto rxPinLocation = Pin::uart_rx{};
+    static constexpr auto txPinLocation = Pin::uart_tx{};
+    static constexpr auto baudRate      = 115200;
+    static constexpr auto dataBits      = Kvasir::UART::DataBits::_8;
+    static constexpr auto parity        = Kvasir::UART::Parity::none;
+    static constexpr auto stopBits      = Kvasir::UART::StopBits::_1;
+    static constexpr auto isrPriority   = 3;
+};
+
 struct PinConfig {
     static constexpr auto powerClockEnable = list(
       clear(Kvasir::Peripheral::RESETS::Registers<>::RESET::io_bank0),
diff --git a/src/main.cpp b/src/main.cpp
index cd870aa..800b84c 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2,16 +2,36 @@
 //
 
 #include <cmake_git_version/version.hpp>
+#include <kvasir/Util/StaticVector.hpp>
+
+template<typename Buffer>
+static void print(Buffer& buffer, std::string_view s) {
+    buffer.resize(s.size());
+    std::transform(s.begin(), s.end(), buffer.begin(), [](auto x) {
+        return static_cast<std::byte>(x);
+    });
+    UC_LOG_D("{}",s);
+    Uart::send_nocopy(buffer);
+}
 
 int main() {
     UC_LOG_D("{}", CMakeGitVersion::FullVersion);
-    auto next = Clock::now();
+    Kvasir::StaticVector<std::byte, 128> buffer;
+    auto                                 next = Clock::now();
+    bool                                 on   = false;
     while(true) {
         auto const now = Clock::now();
         if(now > next) {
-            UC_LOG_D("foo");
-            next += 1s;
-            apply(toggle(HW::Pin::led{}));
+            next += 250ms;
+            if(on) {
+                print(buffer, "LED off\n");
+                apply(clear(HW::Pin::led{}));
+            } else {
+                print(buffer, "LED on\n");
+                apply(set(HW::Pin::led{}));
+
+            }
+            on = !on;
         }
 
         StackProtector::handler();
diff --git a/wokwi.toml b/wokwi.toml
new file mode 100644
index 0000000..abb072a
--- /dev/null
+++ b/wokwi.toml
@@ -0,0 +1,4 @@
+[wokwi]
+version = 1
+firmware = "build/release_flash.uf2"
+elf = "build/release.elf"