diff --git a/app/include/app_board.hpp b/app/include/app_board.hpp
new file mode 100644
index 0000000..2b07f96
--- /dev/null
+++ b/app/include/app_board.hpp
@@ -0,0 +1,19 @@
+//
+// Created by erki on 15.07.22.
+//
+
+#ifndef SKL_TUNNEL_APP_BOARD_HPP
+#define SKL_TUNNEL_APP_BOARD_HPP
+
+#include <cstdint>
+
+namespace App::Board
+{
+
+void setup();
+
+std::uint32_t systickGet();
+
+}
+
+#endif //SKL_TUNNEL_APP_BOARD_HPP
diff --git a/app/include/app_transparent_client.hpp b/app/include/app_transparent_client.hpp
index 65d07da..fb428a9 100644
--- a/app/include/app_transparent_client.hpp
+++ b/app/include/app_transparent_client.hpp
@@ -5,7 +5,11 @@
 #ifndef SKL_TUNNEL_APP_TRANSPARENT_CLIENT_HPP
 #define SKL_TUNNEL_APP_TRANSPARENT_CLIENT_HPP
 
+#include <optional>
+#include <utility_function.hpp>
+
 #include "app_settings.hpp"
+#include "radio_interrupts.hpp"
 
 namespace radio
 {
@@ -20,14 +24,20 @@ class TransparentClient
 public:
   TransparentClient(const RadioSettings& initial_settings);
 
-  void apply_settings(const RadioSettings& settings);
-
   TransparentClient(const TransparentClient&) = delete;
   TransparentClient(TransparentClient&&) = delete;
   TransparentClient& operator=(const TransparentClient&) = delete;
   TransparentClient& operator=(TransparentClient&&) = delete;
+
+  void apply_settings(const RadioSettings& settings);
+  void process();
 private:
   radio::HwInstance* m_radio;
+  Utility::FunctionOwned<TransparentClient, void (radio::HwInstance*)> m_isr_cb_pointer;
+  std::optional<radio::Interrupts> m_pending_irqs = std::nullopt;
+
+  void m_cbRadioIrqHandler(radio::HwInstance*);
+  void m_processInterrupts();
 };
 
 }
diff --git a/app/src/app_board.cpp b/app/src/app_board.cpp
new file mode 100644
index 0000000..96b42e5
--- /dev/null
+++ b/app/src/app_board.cpp
@@ -0,0 +1,57 @@
+//
+// Created by erki on 15.07.22.
+//
+
+#include "app_board.hpp"
+
+#include "driver_init.h"
+
+#include <utility_logging.hpp>
+#include <utility_asynclogger.hpp>
+#include <utility_staticpointer.hpp>
+
+#include "skullc_samd21_hal.hpp"
+
+namespace Hal = Peripherals::Hal::Samd;
+
+using Logger = Utility::AsyncLogger<Hal::SerialInterfaceAsync<usart_async_descriptor>, Hal::StaticHal, 5, 255>;
+
+namespace
+{
+
+Utility::StaticPointer<Logger> m_logger;
+std::uint32_t m_systick_counter = 0;
+
+void m_txCompleteCb(const usart_async_descriptor* const)
+{
+  m_logger->txCompleteCallback();
+}
+
+}
+
+extern "C" void SysTick_Handler()
+{
+  m_systick_counter++;
+}
+
+namespace App::Board
+{
+
+void setup()
+{
+  // Logging
+  Hal::SerialInterfaceAsync<usart_async_descriptor> usart0{&USART_0};
+  usart0.registerTxCallback(m_txCompleteCb);
+
+  m_logger.setup(usart0);
+  Utility::setLogger(*m_logger);
+
+  SysTick_Config(1000);
+}
+
+std::uint32_t systickGet()
+{
+  return m_systick_counter;
+}
+
+}
diff --git a/app/src/app_transparent_client.cpp b/app/src/app_transparent_client.cpp
index dafecd3..81ef9f0 100644
--- a/app/src/app_transparent_client.cpp
+++ b/app/src/app_transparent_client.cpp
@@ -11,6 +11,7 @@ namespace App
 
 TransparentClient::TransparentClient(const RadioSettings& initial_settings)
   : m_radio(radio::HwInstance::instance())
+  , m_isr_cb_pointer(*this, &TransparentClient::m_cbRadioIrqHandler)
 {
   apply_settings(initial_settings);
 
@@ -27,4 +28,24 @@ void TransparentClient::apply_settings(const RadioSettings& settings)
   m_radio->set_max_retries(settings.retries);
 }
 
+void TransparentClient::process()
+{
+  if (m_pending_irqs)
+    m_processInterrupts();
+}
+
+void TransparentClient::m_cbRadioIrqHandler(radio::HwInstance*)
+{
+  const radio::Interrupts new_irqs = m_radio->get_pending_irq();
+  if (m_pending_irqs)
+    m_pending_irqs = (*m_pending_irqs) | new_irqs;
+  else
+    m_pending_irqs = new_irqs;
+}
+
+void TransparentClient::m_processInterrupts()
+{
+  m_pending_irqs = std::nullopt;
+}
+
 }
diff --git a/atmel_start.c b/atmel_start.c
index 79f252a..04ec4fb 100644
--- a/atmel_start.c
+++ b/atmel_start.c
@@ -6,4 +6,6 @@
 void atmel_start_init(void)
 {
 	system_init();
+
+  SysTick_Config(1000);
 }
diff --git a/main.cpp b/main.cpp
index fcafa87..f1bcde1 100644
--- a/main.cpp
+++ b/main.cpp
@@ -26,13 +26,6 @@ Utility::StaticPointer<App::TransparentClient> m_app;
   while (true);
 }
 
-volatile bool irq_seen = false;
-
-void m_irqHandler(radio::HwInstance*)
-{
-  irq_seen = true;
-}
-
 }
 
 int main()
@@ -49,11 +42,9 @@ int main()
   SKULLC_LOG_DEBUG("Begin.");
 
   const App::RadioSettings settings;
-  Utility::Function<void (radio::HwInstance*)> irq_handler{m_irqHandler};
 
   m_app.setup(settings);
   radio::HwInstance* radio_hw = radio::HwInstance::instance();
-  radio_hw->set_irq_handler(&irq_handler);
 
 	/* Replace with your application code */
 	while (true)
@@ -67,13 +58,6 @@ int main()
 
     SKULLC_LOG_INFO("Status: %d", radio_status);
 
-    if (irq_seen)
-    {
-      irq_seen = false;
-      const radio::Interrupts irqs = radio_hw->get_pending_irq();
-      SKULLC_LOG_INFO("IRQ received. %X", std::uint8_t(irqs));
-    }
-
     delay_ms(1000);
 	}
 }