diff --git a/modules/control/Firmware/src/Messages/Parser.cpp b/modules/control/Firmware/src/Messages/Parser.cpp
index 0f1a898..a7476ea 100644
--- a/modules/control/Firmware/src/Messages/Parser.cpp
+++ b/modules/control/Firmware/src/Messages/Parser.cpp
@@ -1,7 +1,48 @@
 #include "Parser.h"
+#include <etl/vector.h>
 
-message::parser::StateVisitor::StateVisitor(etl::byte_stream_reader &sreader)
-    : stream{sreader} {}
+message::parser::StateVisitor::StateVisitor(
+    etl::byte_stream_reader &&sreader,
+    etl::function<void, etl::string_view> invalidCallback,
+    etl::function<void, etl::span<const char>> messageLightDataCallback,
+    etl::function<void, etl::span<const char>> messageInfoCallback,
+    etl::function<void, etl::span<const char>> messageWarningCallback,
+    etl::function<void, etl::span<const char>> messageErrorCallback,
+    etl::function<void, etl::span<const char>> messageSuccessCallback,
+    etl::function<void, uint32_t> settingsSetBaudCallback,
+    etl::function<void, etl::span<const char>> settingsWifiPasswordCallback,
+    etl::function<void, etl::span<const char>> settingsWifiSSIDCallback,
+    etl::function<void, void> lightControlOnCallback,
+    etl::function<void, void> lightControlOffCallback,
+    etl::function<void, uint8_t> lightControlToggleCallback,
+    etl::function<void, uint8_t> lightControlIncreaseCallback,
+    etl::function<void, uint8_t> lightControlDecreaseCallback,
+    etl::function<void, void> commandRequestLightDataCallback,
+    etl::function<void, void> commandEnterConsoleFlashingCallback,
+    etl::function<void, void> commandExitConsoleFlashingCallback,
+    etl::function<void, void> commandPairBluetoothCallback,
+    etl::function<void, void> commandHelpCallback,
+    etl::function<void, void> commandVersionCallback)
+    : stream{etl::move(sreader)}, invalidCallback{invalidCallback},
+      messageLightDataCallback{messageLightDataCallback},
+      messageInfoCallback{messageInfoCallback},
+      messageWarningCallback{messageWarningCallback},
+      messageErrorCallback{messageErrorCallback},
+      messageSuccessCallback{messageSuccessCallback},
+      settingsSetBaudCallback{settingsSetBaudCallback},
+      settingsWifiPasswordCallback{settingsWifiPasswordCallback},
+      settingsWifiSSIDCallback{settingsWifiSSIDCallback},
+      lightControlOnCallback{lightControlOnCallback},
+      lightControlOffCallback{lightControlOffCallback},
+      lightControlToggleCallback{lightControlToggleCallback},
+      lightControlIncreaseCallback{lightControlIncreaseCallback},
+      lightControlDecreaseCallback{lightControlDecreaseCallback},
+      commandRequestLightDataCallback{commandRequestLightDataCallback},
+      commandEnterConsoleFlashingCallback{commandEnterConsoleFlashingCallback},
+      commandExitConsoleFlashingCallback{commandExitConsoleFlashingCallback},
+      commandPairBluetoothCallback{commandPairBluetoothCallback},
+      commandHelpCallback{commandHelpCallback}, commandVersionCallback{
+                                                    commandVersionCallback} {}
 
 auto message::parser::StateVisitor::operator()(state::ModeSelection) -> State {
   if (!stream.available<uint8_t>()) {
@@ -58,25 +99,76 @@ auto message::parser::StateVisitor::operator()(state::Message) -> State {
     return state::Invalid{};
   }
 }
+
 auto message::parser::StateVisitor::operator()(state::MessageLightData)
     -> State {
-  messageLightDataCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("MessageLightData: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto msg = stream.read<char>(stream.available<char>());
+  if (!msg.has_value()) {
+    invalidCallback("MessageLightData: Message has no value");
+    return state::Invalid{};
+  }
+  messageLightDataCallback(msg.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::MessageInfo) -> State {
-  messageInfoCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("MessageInfo: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto msg = stream.read<char>(stream.available<char>());
+  if (!msg.has_value()) {
+    invalidCallback("MessageInfo: Message has no value");
+    return state::Invalid{};
+  }
+  messageInfoCallback(msg.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::MessageWarning) -> State {
-  messageWarningCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("MessageWarning: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto msg = stream.read<char>(stream.available<char>());
+  if (!msg.has_value()) {
+    invalidCallback("MessageWarning: Message has no value");
+    return state::Invalid{};
+  }
+  messageWarningCallback(msg.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::MessageError) -> State {
-  messageErrorCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("MessageError: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto msg = stream.read<char>(stream.available<char>());
+  if (!msg.has_value()) {
+    invalidCallback("MessageError: Message has no value");
+    return state::Invalid{};
+  }
+  messageErrorCallback(msg.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::MessageSuccess) -> State {
-  messageSuccessCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("MessageSuccess: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto msg = stream.read<char>(stream.available<char>());
+  if (!msg.has_value()) {
+    invalidCallback("MessageSuccess: Message has no value");
+    return state::Invalid{};
+  }
+  messageSuccessCallback(msg.value());
   return state::Complete{};
 }
 
@@ -106,17 +198,51 @@ auto message::parser::StateVisitor::operator()(state::Settings) -> State {
 }
 auto message::parser::StateVisitor::operator()(state::SettingsSetBaud)
     -> State {
-  settingsSetBaudCallback();
+  if (!stream.available<uint32_t>()) {
+    invalidCallback("Settings: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto baud = stream.read<uint32_t>();
+
+  if (!baud.has_value()) {
+    invalidCallback("SettingsSetBaud: Baud has no value");
+    return state::Invalid{};
+  }
+
+  settingsSetBaudCallback(baud.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::SettingsWifiPassword)
     -> State {
-  settingsWifiPasswordCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("SettingsWifiPassword: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto passwd = stream.read<char>(stream.available<char>());
+  if (!passwd.has_value()) {
+    invalidCallback("SettingsWifiPassword: Passwd has no value");
+    return state::Invalid{};
+  }
+
+  settingsWifiPasswordCallback(passwd.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::SettingsWifiSSID)
     -> State {
-  settingsWifiSSIDCallback();
+  if (!stream.available<char>()) {
+    invalidCallback("SettingsWifiSSID: Stream not available");
+    return state::Invalid{};
+  }
+
+  auto ssid = stream.read<char>(stream.available<char>());
+  if (!ssid.has_value()) {
+    invalidCallback("SettingsWifiSSID: SSID has no value");
+    return state::Invalid{};
+  }
+
+  settingsWifiSSIDCallback(ssid.value());
   return state::Complete{};
 }
 
@@ -171,8 +297,14 @@ auto message::parser::StateVisitor::operator()(state::LightControlToggle)
   if (stream.available_bytes() > 1) {
     invalidCallback("LightControlToggle: Too many bytes left");
     return state::Invalid{};
+  } else if (!stream.available<uint8_t>()) {
+    invalidCallback("LightControlToggle: Stream not available");
+    return state::Invalid{};
   }
-  lightControlToggleCallback();
+
+  auto id = stream.read<uint8_t>();
+
+  lightControlToggleCallback(id.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::LightControlIncrease)
@@ -180,8 +312,14 @@ auto message::parser::StateVisitor::operator()(state::LightControlIncrease)
   if (stream.available_bytes() > 1) {
     invalidCallback("LightControlIncrease: Too many bytes left");
     return state::Invalid{};
+  } else if (!stream.available<uint8_t>()) {
+    invalidCallback("LightControlIncrease: Stream not available");
+    return state::Invalid{};
   }
-  lightControlIncreaseCallback();
+
+  auto id = stream.read<uint8_t>();
+
+  lightControlIncreaseCallback(id.value());
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::LightControlDecrease)
@@ -189,8 +327,14 @@ auto message::parser::StateVisitor::operator()(state::LightControlDecrease)
   if (stream.available_bytes() > 1) {
     invalidCallback("LightControlDecrease: Too many bytes left");
     return state::Invalid{};
+  } else if (!stream.available<uint8_t>()) {
+    invalidCallback("LightControlDecrease: Stream not available");
+    return state::Invalid{};
   }
-  lightControlDecreaseCallback();
+
+  auto id = stream.read<uint8_t>();
+
+  lightControlDecreaseCallback(id.value());
   return state::Complete{};
 }
 
@@ -257,10 +401,20 @@ auto message::parser::StateVisitor::operator()(state::CommandPairBluetooth)
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::CommandHelp) -> State {
+  if (stream.available_bytes() > 0) {
+    invalidCallback("CommandHelp: Too many bytes left");
+    return state::Invalid{};
+  }
+
   commandHelpCallback();
   return state::Complete{};
 }
 auto message::parser::StateVisitor::operator()(state::CommandVersion) -> State {
+  if (stream.available_bytes() > 0) {
+    invalidCallback("CommandVersion: Too many bytes left");
+    return state::Invalid{};
+  }
+
   commandVersionCallback();
   return state::Complete{};
 }
@@ -272,14 +426,52 @@ auto message::parser::StateVisitor::operator()(state::Invalid) -> State {
   return state::Invalid{};
 }
 
-auto message::parser::parse(etl::byte_stream_reader &reader) -> void {
-  StateVisitor visitor{reader};
+auto message::parser::parse(
+    etl::byte_stream_reader &&reader,
+    etl::function<void, etl::string_view> invalidCallback,
+    etl::function<void, etl::span<const char>> messageLightDataCallback,
+    etl::function<void, etl::span<const char>> messageInfoCallback,
+    etl::function<void, etl::span<const char>> messageWarningCallback,
+    etl::function<void, etl::span<const char>> messageErrorCallback,
+    etl::function<void, etl::span<const char>> messageSuccessCallback,
+    etl::function<void, uint32_t> settingsSetBaudCallback,
+    etl::function<void, etl::span<const char>> settingsWifiPasswordCallback,
+    etl::function<void, etl::span<const char>> settingsWifiSSIDCallback,
+    etl::function<void, void> lightControlOnCallback,
+    etl::function<void, void> lightControlOffCallback,
+    etl::function<void, uint8_t> lightControlToggleCallback,
+    etl::function<void, uint8_t> lightControlIncreaseCallback,
+    etl::function<void, uint8_t> lightControlDecreaseCallback,
+    etl::function<void, void> commandRequestLightDataCallback,
+    etl::function<void, void> commandEnterConsoleFlashingCallback,
+    etl::function<void, void> commandExitConsoleFlashingCallback,
+    etl::function<void, void> commandPairBluetoothCallback,
+    etl::function<void, void> commandHelpCallback,
+    etl::function<void, void> commandVersionCallback) -> void {
+  StateVisitor visitor{etl::move(reader),
+                       invalidCallback,
+                       messageLightDataCallback,
+                       messageInfoCallback,
+                       messageWarningCallback,
+                       messageErrorCallback,
+                       messageSuccessCallback,
+                       settingsSetBaudCallback,
+                       settingsWifiPasswordCallback,
+                       settingsWifiSSIDCallback,
+                       lightControlOnCallback,
+                       lightControlOffCallback,
+                       lightControlToggleCallback,
+                       lightControlIncreaseCallback,
+                       lightControlDecreaseCallback,
+                       commandRequestLightDataCallback,
+                       commandEnterConsoleFlashingCallback,
+                       commandExitConsoleFlashingCallback,
+                       commandPairBluetoothCallback,
+                       commandHelpCallback,
+                       commandVersionCallback};
   State state{state::ModeSelection{}};
   while (!etl::holds_alternative<state::Invalid>(state) &&
          !etl::holds_alternative<state::Complete>(state)) {
     state = etl::visit(visitor, state);
   }
-  if (etl::holds_alternative<state::Invalid>(state)) {
-    // TODO: error
-  }
 }
diff --git a/modules/control/Firmware/src/Messages/Parser.h b/modules/control/Firmware/src/Messages/Parser.h
index dbd93aa..d9e8774 100644
--- a/modules/control/Firmware/src/Messages/Parser.h
+++ b/modules/control/Firmware/src/Messages/Parser.h
@@ -2,6 +2,8 @@
 #include "Protocol.h"
 #include <etl/byte_stream.h>
 #include <etl/function.h>
+#include <etl/span.h>
+#include <etl/string_view.h>
 #include <etl/variant.h>
 
 namespace message {
@@ -47,11 +49,53 @@ using State = etl::variant<
     state::CommandExitConsoleFlashing, state::CommandPairBluetooth,
     state::CommandHelp, state::CommandVersion, state::Complete>;
 
-void parse(etl::byte_stream_reader &reader);
+void parse(
+    etl::byte_stream_reader &&reader,
+    etl::function<void, etl::string_view> invalidCallback,
+    etl::function<void, etl::span<const char>> messageLightDataCallback,
+    etl::function<void, etl::span<const char>> messageInfoCallback,
+    etl::function<void, etl::span<const char>> messageWarningCallback,
+    etl::function<void, etl::span<const char>> messageErrorCallback,
+    etl::function<void, etl::span<const char>> messageSuccessCallback,
+    etl::function<void, uint32_t> settingsSetBaudCallback,
+    etl::function<void, etl::span<const char>> settingsWifiPasswordCallback,
+    etl::function<void, etl::span<const char>> settingsWifiSSIDCallback,
+    etl::function<void, void> lightControlOnCallback,
+    etl::function<void, void> lightControlOffCallback,
+    etl::function<void, uint8_t> lightControlToggleCallback,
+    etl::function<void, uint8_t> lightControlIncreaseCallback,
+    etl::function<void, uint8_t> lightControlDecreaseCallback,
+    etl::function<void, void> commandRequestLightDataCallback,
+    etl::function<void, void> commandEnterConsoleFlashingCallback,
+    etl::function<void, void> commandExitConsoleFlashingCallback,
+    etl::function<void, void> commandPairBluetoothCallback,
+    etl::function<void, void> commandHelpCallback,
+    etl::function<void, void> commandVersionCallback);
 
 class StateVisitor {
 public:
-  StateVisitor(etl::byte_stream_reader &);
+  StateVisitor(
+      etl::byte_stream_reader &&sreader,
+      etl::function<void, etl::string_view> invalidCallback,
+      etl::function<void, etl::span<const char>> messageLightDataCallback,
+      etl::function<void, etl::span<const char>> messageInfoCallback,
+      etl::function<void, etl::span<const char>> messageWarningCallback,
+      etl::function<void, etl::span<const char>> messageErrorCallback,
+      etl::function<void, etl::span<const char>> messageSuccessCallback,
+      etl::function<void, uint32_t> settingsSetBaudCallback,
+      etl::function<void, etl::span<const char>> settingsWifiPasswordCallback,
+      etl::function<void, etl::span<const char>> settingsWifiSSIDCallback,
+      etl::function<void, void> lightControlOnCallback,
+      etl::function<void, void> lightControlOffCallback,
+      etl::function<void, uint8_t> lightControlToggleCallback,
+      etl::function<void, uint8_t> lightControlIncreaseCallback,
+      etl::function<void, uint8_t> lightControlDecreaseCallback,
+      etl::function<void, void> commandRequestLightDataCallback,
+      etl::function<void, void> commandEnterConsoleFlashingCallback,
+      etl::function<void, void> commandExitConsoleFlashingCallback,
+      etl::function<void, void> commandPairBluetoothCallback,
+      etl::function<void, void> commandHelpCallback,
+      etl::function<void, void> commandVersionCallback);
   State operator()(state::ModeSelection);
   State operator()(state::Message);
   State operator()(state::MessageLightData);
@@ -86,19 +130,19 @@ private:
   etl::byte_stream_reader stream;
   // TODO: callback function parameter types
   etl::function<void, etl::string_view> invalidCallback;
-  etl::function<void, void> messageLightDataCallback;
-  etl::function<void, void> messageInfoCallback;
-  etl::function<void, void> messageWarningCallback;
-  etl::function<void, void> messageErrorCallback;
-  etl::function<void, void> messageSuccessCallback;
-  etl::function<void, void> settingsSetBaudCallback;
-  etl::function<void, void> settingsWifiPasswordCallback;
-  etl::function<void, void> settingsWifiSSIDCallback;
+  etl::function<void, etl::span<const char>> messageLightDataCallback;
+  etl::function<void, etl::span<const char>> messageInfoCallback;
+  etl::function<void, etl::span<const char>> messageWarningCallback;
+  etl::function<void, etl::span<const char>> messageErrorCallback;
+  etl::function<void, etl::span<const char>> messageSuccessCallback;
+  etl::function<void, uint32_t> settingsSetBaudCallback;
+  etl::function<void, etl::span<const char>> settingsWifiPasswordCallback;
+  etl::function<void, etl::span<const char>> settingsWifiSSIDCallback;
   etl::function<void, void> lightControlOnCallback;
   etl::function<void, void> lightControlOffCallback;
-  etl::function<void, void> lightControlToggleCallback;
-  etl::function<void, void> lightControlIncreaseCallback;
-  etl::function<void, void> lightControlDecreaseCallback;
+  etl::function<void, uint8_t> lightControlToggleCallback;
+  etl::function<void, uint8_t> lightControlIncreaseCallback;
+  etl::function<void, uint8_t> lightControlDecreaseCallback;
   etl::function<void, void> commandRequestLightDataCallback;
   etl::function<void, void> commandEnterConsoleFlashingCallback;
   etl::function<void, void> commandExitConsoleFlashingCallback;