부팅 시 serial packet이 전송되지 않는 버그 수정

Reviewed-on: #41

README.md

@@ -214,3 +214,10 @@
   - `loadFluenceTable()`, `loadHzTable()`, `calculateInterpolatedC()` 영향 확인
 - 성능/안정성 이슈 시
   - `txPacketLoop()` 주기, `RX_TIMEOUT_THRESHOLD`, DB 로그 적재량 점검
+
+## 10) Troubleshooting
+
+- 시리얼 초기 TX 누락(Startup race, FD 설명, 수정 내역):
+  - [`docs/serial_tx_startup_race.md`](docs/serial_tx_startup_race.md)
+- 변경 요약 문서(`git diff` 기준):
+  - [`docs/change_summary_2026-03-04.md`](docs/change_summary_2026-03-04.md)

app/src/main/java/com/laseroptek/raman/data/source/preference/Preference.kt

@@ -88,4 +88,7 @@ interface Preference {
     suspend fun getPowerSupplySerialListFromPreference(): Flow<List<String>>
     /////
 
+    suspend fun saveInfoChartLineStates(states: Map<String, Boolean>)
+    suspend fun getInfoChartLineStates(): Flow<Map<String, Boolean>>
+
 }

app/src/main/java/com/laseroptek/raman/repository/PreferenceRepository.kt

@@ -68,6 +68,9 @@ class PreferenceRepository(private val context: Context) : Preference {
         val PRODUCT_SERIAL = stringPreferencesKey("PRODUCT_SERIAL")
         val LASER_HAND_SERIAL = stringPreferencesKey("LASER_HAND_SERIAL")
         val POWER_SUPPLY_SERIAL = stringPreferencesKey("POWER_SUPPLY_SERIAL")
+
+        // InfoScreen Chart Checkboxes
+        val INFO_CHART_LINE_STATES = stringPreferencesKey("INFO_CHART_LINE_STATES")
     }
 
     override suspend fun clearAllPreferences() {
@@ -559,4 +562,31 @@ class PreferenceRepository(private val context: Context) : Preference {
             emit(listOf("B", "U", "O", "C", "L", "D"))
         }
     }
+
+    override suspend fun saveInfoChartLineStates(states: Map<String, Boolean>) {
+        try {
+            val stateJson = gson.toJson(states)
+            context.datastore.edit { preferences ->
+                preferences[INFO_CHART_LINE_STATES] = stateJson
+            }
+        } catch (e: Exception) {
+            Timber.e(e, "Failed to serialize INFO_CHART_LINE_STATES to JSON.")
+        }
+    }
+
+    override suspend fun getInfoChartLineStates(): Flow<Map<String, Boolean>> {
+        return context.datastore.data.map { preferences ->
+            preferences[INFO_CHART_LINE_STATES]
+        }.distinctUntilChanged().map { jsonString ->
+            if (!jsonString.isNullOrBlank()) {
+                val type = object : TypeToken<Map<String, Boolean>>() {}.type
+                gson.fromJson<Map<String, Boolean>>(jsonString, type) ?: emptyMap()
+            } else {
+                emptyMap()
+            }
+        }.catch { e ->
+            Timber.e(e, "Failed to get or parse INFO_CHART_LINE_STATES. Emitting default.")
+            emit(emptyMap())
+        }
+    }
 }

app/src/main/java/com/laseroptek/raman/ui/MainActivity.kt

@@ -260,9 +260,11 @@ class MainActivity : ComponentActivity() {
                     // This prevents serial interrupts from stealing CPU during the first frame.
                     delay(200)
 
-                    vm.txPacketOnce()
-
+                    // IMPORTANT:
+                    // rxPacketLoop() starts serial open() asynchronously.
+                    // Start RX first so txPacketOnce() is less likely to run before FD is ready.
                     vm.rxPacketLoop()
+                    vm.txPacketOnce()
                     vm.txPacketLoop()
 
                     Timber.d("System fully operational.")

app/src/main/java/com/laseroptek/raman/ui/screens/config/ConfigScreen.kt

@@ -439,15 +439,15 @@ fun ConfigScreen(
                                     mainViewModel.saveGuideBeamToPreference()
                                 }
 
-                                /*
-                                val value = when(guideBeam.toInt()) {
-                                    0 -> 0
-                                    1 -> guideBeamMin
-                                    10 -> guideBeamMax
-                                    else -> (guideBeamMin + (guideBeam.toInt() - 1) * ((guideBeamMax - guideBeamMin) / 9))
+                                // Guide Beam step mapping (0~10):
+                                // 0 -> fixed 0
+                                // 1~10 -> min~max range in 10 steps (10 -> max)
+                                val step = guideBeam.toInt().coerceIn(0, 10)
+                                val value = if (step == 0) {
+                                    0
+                                } else {
+                                    guideBeamMin + ((step-1) * (guideBeamMax - guideBeamMin) / 9)
                                 }
-                                */
-                                val value = (guideBeamMin + (guideBeam.toInt() - 1) * ((guideBeamMax - guideBeamMin) / 9))
 
                                 Timber.d("guideBeam: $value, guideBeamMax: $guideBeamMax, guideBeamMin: $guideBeamMin")
                                 mainViewModel.txPacket(READ_WRITE.WRITE, CMD.GUIDE_BEAM, GuideBeam(value = value))

app/src/main/java/com/laseroptek/raman/ui/screens/engineer/HourItemView.kt

@@ -31,7 +31,7 @@ fun HourItemView(
     modifier: Modifier = Modifier,
     hour: Int = 0,
     onClick: () -> Unit = {},
-    title:String = ""
+    title: String = ""
 ) {
     Row(modifier = modifier,
         horizontalArrangement = Arrangement.SpaceBetween,

app/src/main/java/com/laseroptek/raman/ui/screens/engineer/LifeTimeView.kt

@@ -32,11 +32,11 @@ fun LifeTimeView(
 ) {
     Column(modifier = Modifier
         //.noRippleClickable(onClick = onClick)
-        .size(388.px.dp, 276.px.dp)
+        .size(388.px.dp, 258.px.dp)
         .clip(RoundedCornerShape(12.px.dp))
         .border(width = 1.px.dp, color = Color(209, 209, 209), shape = RoundedCornerShape(10.px.dp))
         .background(Color.White)
-        .padding(16.px.dp),
+        .padding(3.px.dp, 16.px.dp),
         verticalArrangement = Arrangement.SpaceEvenly,
         horizontalAlignment = Alignment.CenterHorizontally
     ) {
@@ -55,11 +55,11 @@ fun LifeTimeView(
                 ),
         )
 
-        Spacer(modifier = Modifier.height(10.px.dp))
+        Spacer(modifier = Modifier.height(2.px.dp))
 
         // Temp 0..7
         for (i in 0..lifeTimeTypes.size -1) {
-            val hour = when (i) {
+            val value = when (i) {
                 0 -> lifeTime.lamp
                 1 -> lifeTime.hp5x5
                 2 -> lifeTime.hp7x7
@@ -70,22 +70,35 @@ fun LifeTimeView(
                 7 -> lifeTime.water
                 else -> 0
             }
-            HourItemView(
-                modifier = Modifier
+            val modifier = Modifier
                 .fillMaxSize()
                 .weight(1f)
                 .padding(
                     start = 20.px.dp,
                     end = 20.px.dp,
                     //bottom = 10.px.dp
-                    ),
-                title = lifeTimeTypes[i],
-                hour = hour,
-                onClick = {
-                    Timber.d("onClick > Temp $i (${lifeTimeTypes[i]})")
+                )
+            val title = lifeTimeTypes[i]
+            val onItemClick = {
+                Timber.d("onClick > Temp $i ($title)")
                 onClick.invoke(i)
             }
+
+            if (i <= 5) {
+                CountItemView(
+                    modifier = modifier,
+                    title = title,
+                    count = value,
+                    onClick = onItemClick
                 )
+            } else {
+                HourItemView(
+                    modifier = modifier,
+                    title = title,
+                    hour = value,
+                    onClick = onItemClick
+                )
+            }
 
             if (i < lifeTimeTypes.size -1) {
                 HorizontalDivider(

app/src/main/java/com/laseroptek/raman/ui/screens/engineer/TemperatureView.kt

@@ -42,7 +42,7 @@ fun TemperatureView(
         .clip(RoundedCornerShape(12.px.dp))
         .border(width = 1.px.dp, color = Color(209, 209, 209), shape = RoundedCornerShape(10.px.dp))
         .background(Color.White)
-        .padding(16.px.dp),
+        .padding(3.px.dp, 16.px.dp),
         verticalArrangement = Arrangement.SpaceEvenly,
         horizontalAlignment = Alignment.CenterHorizontally
     ) {

app/src/main/java/com/laseroptek/raman/ui/screens/home/HomeScreen.kt

@@ -35,6 +35,7 @@ import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.hilt.lifecycle.viewmodel.compose.hiltViewModel
 import com.laseroptek.raman.const.LaserParameter
+import com.laseroptek.raman.const.LASER_STATUS
 import com.laseroptek.raman.const.LaserStatusType
 import com.laseroptek.raman.const.MAX_LASER_COUNT
 import com.laseroptek.raman.const.PresetButtonType
@@ -92,10 +93,18 @@ fun HomeScreen(
 
     val presetList by mainViewModel.presetList.collectAsState()
 
-    LaunchedEffect(Unit) {
+    LaunchedEffect(lampCount, lifeTime.lamp, laserStatus.laserStatus) {
         Timber.d("LaunchedEffect - HomeScreen")
         focusManager.clearFocus(force = true) // Hide the keyboard
 
+        // Ensure the system returns to StandBy when lamp thresholds are exceeded
+        val lampLifetimeLimit = lifeTime.lamp
+        val reachedLifetimeLimit = lampLifetimeLimit > 0 && lampCount >= lampLifetimeLimit
+        if (reachedLifetimeLimit && laserStatus.laserStatus != LASER_STATUS.STAND_BY) {
+            Timber.d("HomeScreen load - forcing StandBy state due to lamp count limit")
+            mainViewModel.txLaserStatusEntry(LASER_STATUS.STAND_BY)
+        }
+
         Timber.d("Attempted to hide keyboard on EngineerScreen launch")
     }
 
@@ -482,6 +491,18 @@ fun HomeScreen(
                             return@StandByButton
                         }
 
+                        val lampLifetimeLimit = lifeTime.lamp
+                        if (lampLifetimeLimit > 0 && lampCount >= lampLifetimeLimit) {
+                            Toast.makeText(
+                                context,
+                                "Lamp lifetime limit reached",
+                                Toast.LENGTH_SHORT
+                            ).show()
+                            return@StandByButton
+                        }
+
+
+
                         val hpCount = mainViewModel.getHPCount()
                         if (hpCount < 1) {
                             Toast.makeText(

app/src/main/java/com/laseroptek/raman/ui/screens/home/dcd/DcdSettingPopup.kt

@@ -334,7 +334,7 @@ fun DcdSettingPopup(
                         modifier = Modifier
                             .fillMaxHeight()
                             .size(40.px.dp, 210.px.dp),
-                        chargeRate = gasChargeRate.toInt()
+                        chargeRate = gasChargeRate
                     )
 
                     // Icon

app/src/main/java/com/laseroptek/raman/ui/screens/home/dcd/GradientSlider.kt

@@ -28,14 +28,26 @@ import com.laseroptek.raman.ui.screens.main.MainViewModel
 import com.laseroptek.raman.utils.DefaultDispatcherProvider
 import com.laseroptek.raman.utils.ext.px
 import timber.log.Timber
+import kotlin.math.abs
+import kotlin.math.ceil
 
 
 @Composable
 fun GradientSlider(
     modifier: Modifier = Modifier,
-    chargeRate: Int = 0, // Value from (0 .. 100)
+    chargeRate: Float = 0f,
 ) {
-    val chargeIndex = ((chargeRate.coerceIn(0, 100) + 4) / 5).toInt()   // 0..19
+    val normalizedRate = chargeRate.coerceIn(0f, 100f)
+    val bucket = normalizedRate / 5f
+    val remainder = normalizedRate % 5f
+    val isExactMultiple = abs(remainder) < 0.0001f
+
+    val chargeIndex = when {
+        normalizedRate == 0f -> -1
+        isExactMultiple -> (bucket - 1f).toInt().coerceAtLeast(-1)
+        else -> (ceil(bucket.toDouble()).toInt() - 1)
+    }.coerceIn(-1, 19)
+
     Timber.d("chargeRate: $chargeRate, chargeIndex: $chargeIndex")
 
     Box(
@@ -103,6 +115,6 @@ fun GradientSliderPreview(
         //mainViewModel = mainViewModel
         modifier = Modifier
             .size(40.px.dp, 210.px.dp),
-        chargeRate =  20
+        chargeRate = 20f
     )
 }

app/src/main/java/com/laseroptek/raman/ui/screens/home/preset/PresetIconButton.kt

@@ -108,15 +108,15 @@ fun PresetIconButton(
         Image(
             painter = painterResource(id =
                 if (type == PresetButtonType.SAVE) {
-                    R.drawable.ic_preset_save
+                    R.drawable.ic_preset_save2
                 } else {
                     R.drawable.ic_preset_load
                 }
             ),
             contentDescription = "",
             modifier = Modifier
-                .size(20.px.dp),
-            contentScale = ContentScale.Crop
+                .size(30.px.dp),
+            contentScale = ContentScale.Fit
         )
     }
 }

app/src/main/java/com/laseroptek/raman/ui/screens/home/preset/PresetLoadPopup.kt

@@ -552,12 +552,12 @@ fun PresetLoadPopup(
                     horizontalArrangement = Arrangement.Center,
                     verticalAlignment = Alignment.CenterVertically
                 ) {
-                    Spacer(Modifier.weight(1f))
-
                     if (isEditMode) {
                         ////////////////////////////////////////////////////
                         // Edit Mode
 
+                        Spacer(modifier = Modifier.width(10.px.dp))
+
                         // Preset Delete (Delete confirm popup)
                         Box(
                             modifier = Modifier
@@ -578,7 +578,7 @@ fun PresetLoadPopup(
                             )
                         }
 
-                        Spacer(Modifier.width(10.px.dp))
+                        Spacer(Modifier.weight(1f))
 
                         // Preset Cancel (Reload selected item from mainViewModel)
                         Box(
@@ -646,7 +646,7 @@ fun PresetLoadPopup(
                                     Timber.d("onClick - Confirm Save")
 
                                     // Check empty names and conflict priority exist in the preset viewmodel's presetList
-                                    val listToValidate = presetViewModel.presetList.value
+                                    var listToValidate = presetViewModel.presetList.value
 
                                     // Check for any presets with an empty name
                                     val hasEmptyName =
@@ -678,18 +678,32 @@ fun PresetLoadPopup(
                                     }
 
                                     // Check for duplicate priorities (ignoring priority 0)
-                                    val priorityConflicts = listToValidate
-                                        .filter { it.priority > 0 } // Only consider prioritized items
-                                        .groupBy { it.priority }   // Group them by priority
-                                        .any { it.value.size > 1 } // Check if any group is larger than 1
+                                    val duplicatePriorityGroups = listToValidate
+                                        .filter { it.priority > 0 }
+                                        .groupBy { it.priority }
+                                        .filter { it.value.size > 1 }
 
-                                    if (priorityConflicts) {
-                                        Toast.makeText(
-                                            context,
-                                            "There are duplicate priorities. Please ensure each priority is unique.",
-                                            Toast.LENGTH_LONG
-                                        ).show()
-                                        return@noRippleClickable // Stop the process
+                                    if (duplicatePriorityGroups.isNotEmpty()) {
+                                        val resolvedList = listToValidate.map { it.copy() }.toMutableList()
+                                        val selectedPreset = resolvedList.getOrNull(selectedPresetIndex)
+
+                                        duplicatePriorityGroups.forEach { (priorityValue, presets) ->
+                                            val keeperId = presets
+                                                .firstOrNull { preset ->
+                                                    selectedPreset != null && preset.id == selectedPreset.id
+                                                }
+                                                ?.id
+                                                ?: presets.first().id
+
+                                            resolvedList.forEachIndexed { index, preset ->
+                                                if (preset.priority == priorityValue && preset.id != keeperId) {
+                                                    resolvedList[index] = preset.copy(priority = 0)
+                                                }
+                                            }
+                                        }
+
+                                        presetViewModel.setPresetList(resolvedList)
+                                        listToValidate = resolvedList
                                     }
 
                                     Timber.d("Validation successful. Saving list to MainViewModel.")
@@ -729,7 +743,11 @@ fun PresetLoadPopup(
                                 contentScale = ContentScale.Crop
                             )
                         }
+
+                        Spacer(modifier = Modifier.width(10.px.dp))
                     } else {
+                        Spacer(Modifier.weight(1f))
+
                         ////////////////////////////////////////////////////
                         // Select Mode - hide Keyboard
                         focusManager.clearFocus(force = true) // Hide the keyboard
@@ -790,6 +808,8 @@ fun PresetLoadPopup(
                                 contentScale = ContentScale.Crop
                             )
                         }
+
+                        Spacer(modifier = Modifier.width(10.px.dp))
                     }
                 }
 

app/src/main/java/com/laseroptek/raman/ui/screens/info/InfoViewModel.kt

@@ -1,10 +1,14 @@
 package com.laseroptek.raman.ui.screens.info
 
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
+import com.laseroptek.raman.repository.PreferenceRepository
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.launch
 import timber.log.Timber
 import javax.inject.Inject
 
@@ -25,10 +29,13 @@ data class ChartUiState(
     val chamber2State: Boolean = true,
     val basePlateState: Boolean = true,
     val waterState: Boolean = true,
-)
+) {
+    companion object
+}
 
 @HiltViewModel
 class InfoViewModel @Inject constructor(
+    private val preferenceRepository: PreferenceRepository,
 ) : ViewModel() {
 
     // This is the single source of truth for the checkbox states.
@@ -39,7 +46,7 @@ class InfoViewModel @Inject constructor(
     fun toggleLine(line: ChartLine) {
         // .update is a thread-safe way to update the state.
         _chartUiState.update { currentState ->
-            when (line) {
+            val updatedState = when (line) {
                 ChartLine.INT_TEMP -> currentState.copy(intTempState = !currentState.intTempState)
                 ChartLine.EXT_TEMP -> currentState.copy(extTempState = !currentState.extTempState)
                 ChartLine.INT_HUMIDITY -> currentState.copy(intHumidityState = !currentState.intHumidityState)
@@ -50,10 +57,51 @@ class InfoViewModel @Inject constructor(
                 ChartLine.BASE_PLATE -> currentState.copy(basePlateState = !currentState.basePlateState)
                 ChartLine.WATER -> currentState.copy(waterState = !currentState.waterState)
             }
+            persistChartUiState(updatedState)
+            updatedState
         }
     }
 
     init {
         Timber.d("InfoViewModel init")
+        viewModelScope.launch {
+            preferenceRepository.getInfoChartLineStates().collectLatest { savedStates ->
+                if (savedStates.isEmpty()) return@collectLatest
+                _chartUiState.update { ChartUiState.fromPreference(savedStates) }
+            }
+        }
+    }
+
+    private fun persistChartUiState(state: ChartUiState) {
+        viewModelScope.launch {
+            preferenceRepository.saveInfoChartLineStates(state.toPreferenceMap())
+        }
     }
 }
+
+private fun ChartUiState.toPreferenceMap(): Map<String, Boolean> = mapOf(
+    ChartLine.INT_TEMP.name to intTempState,
+    ChartLine.EXT_TEMP.name to extTempState,
+    ChartLine.INT_HUMIDITY.name to intHumidityState,
+    ChartLine.EXT_HUMIDITY.name to extHumidityState,
+    ChartLine.KTP.name to ktpState,
+    ChartLine.CHAMBER1.name to chamber1State,
+    ChartLine.CHAMBER2.name to chamber2State,
+    ChartLine.BASE_PLATE.name to basePlateState,
+    ChartLine.WATER.name to waterState,
+)
+
+private fun ChartUiState.Companion.fromPreference(savedStates: Map<String, Boolean>): ChartUiState {
+    val defaults = ChartUiState()
+    return ChartUiState(
+        intTempState = savedStates[ChartLine.INT_TEMP.name] ?: defaults.intTempState,
+        extTempState = savedStates[ChartLine.EXT_TEMP.name] ?: defaults.extTempState,
+        intHumidityState = savedStates[ChartLine.INT_HUMIDITY.name] ?: defaults.intHumidityState,
+        extHumidityState = savedStates[ChartLine.EXT_HUMIDITY.name] ?: defaults.extHumidityState,
+        ktpState = savedStates[ChartLine.KTP.name] ?: defaults.ktpState,
+        chamber1State = savedStates[ChartLine.CHAMBER1.name] ?: defaults.chamber1State,
+        chamber2State = savedStates[ChartLine.CHAMBER2.name] ?: defaults.chamber2State,
+        basePlateState = savedStates[ChartLine.BASE_PLATE.name] ?: defaults.basePlateState,
+        waterState = savedStates[ChartLine.WATER.name] ?: defaults.waterState,
+    )
+}

app/src/main/java/com/laseroptek/raman/ui/screens/main/MainViewModel.kt

@@ -583,22 +583,22 @@ class MainViewModel @Inject constructor(
         saveGuideBeamMinToPreference()
         saveGuideBeamMaxToPreference()
 
-        // After updating the state, send the packet
-        val newMin = guideBeamMin.value // get the potentially updated value
-        val newMax = guideBeamMax.value // get the potentially updated value
-        val guideBeam = guideBeam.value.toInt()
+        // Engineer 화면에서는 Min/Max 버튼에 따라 표시된 Min 또는 Max 값을 그대로 송신
+        val newMin = guideBeamMin.value
+        val newMax = guideBeamMax.value
+        val value = when (state) {
+            MinMaxUpDownState.MinDown,
+            MinMaxUpDownState.MinUp,
+            MinMaxUpDownState.MinLongDown,
+            MinMaxUpDownState.MinLongUp -> newMin
 
-        /*
-        val value = when(guideBeamValue) {
-            0 -> 0
-            1 -> newMin
-            10 -> newMax
-            else -> (newMin + (guideBeamValue - 1) * ((newMax - newMin) / 9))
+            MinMaxUpDownState.MaxDown,
+            MinMaxUpDownState.MaxUp,
+            MinMaxUpDownState.MaxLongDown,
+            MinMaxUpDownState.MaxLongUp -> newMax
         }
-        */
-        val value = (newMin + (guideBeam - 1) * ((newMax - newMin) / 9))
 
-        Timber.d("guideBeam: $value, guideBeam: $guideBeam, guideBeamMax: $newMax, guideBeamMin: $newMin")
+        Timber.d("Engineer guideBeam tx value: $value, guideBeamMax: $newMax, guideBeamMin: $newMin")
         txPacket(READ_WRITE.WRITE, CMD.GUIDE_BEAM, GuideBeam(value = value))
     }
 
@@ -814,6 +814,15 @@ class MainViewModel @Inject constructor(
     }
 
     fun txPacketOnce() {
+        viewModelScope.launch(dispatcherProvider.io) {
+            // txPacketOnce is called during app startup.
+            // Because serial open() is started in rxPacketLoop() asynchronously,
+            // FD can still be -1 here (startup race). Wait briefly before first TX burst.
+            if (!waitUntilSerialReady()) {
+                Timber.e("txPacketOnce skipped: serial port is not ready (fd=%d)", serialPortRepository.getFD())
+                return@launch
+            }
+
             // viewModel init 으로 이동. 필요.
             // 경고 정보 조회 (주기적 heart beat)
             // repeatOnLifecycle은 Activity가 포그라운드에 있을 때로 한정지어, 특정 Lifecycle이 Trigger 되었을 때 동작하도록 만드는 block 임.
@@ -825,7 +834,7 @@ class MainViewModel @Inject constructor(
             txPacket(READ_WRITE.WRITE, CMD.Q_SWITCH, qSwitch.value)
 
             // tx Guide Beam Write
-        txPacket(READ_WRITE.WRITE, CMD.GUIDE_BEAM, GuideBeam(value = guideBeam.value.toInt()))
+            txPacket(READ_WRITE.WRITE, CMD.GUIDE_BEAM, GuideBeam(value = getGuideBeamTxValue()))
 
             // tx DCD_GAS Write (DEFAULT VALUE)
             txPacket(READ_WRITE.WRITE, CMD.DCD_GAS, dcdGas.value.copy(status = 0x50))
@@ -833,6 +842,32 @@ class MainViewModel @Inject constructor(
             // tx SPRAY_DCD Write (DEFAULT VALUE)
             txPacket(READ_WRITE.WRITE, CMD.SPRAY_DCD, sprayDcd.value)
         }
+    }
+
+    private suspend fun waitUntilSerialReady(
+        timeoutMillis: Long = 2000L,
+        pollIntervalMillis: Long = 20L
+    ): Boolean {
+        // Poll FD until open() completes, with a bounded timeout to avoid blocking forever.
+        val start = System.currentTimeMillis()
+        while (System.currentTimeMillis() - start < timeoutMillis) {
+            if (serialPortRepository.getFD() != -1) return true
+            delay(pollIntervalMillis)
+        }
+        return serialPortRepository.getFD() != -1
+    }
+
+    // Guide Beam step mapping (0~10)
+    // 0 -> fixed 0
+    // 1~10 -> min~max range in 10 steps (10 -> max)
+    private fun getGuideBeamTxValue(): Int {
+        val step = guideBeam.value.toInt().coerceIn(0, 10)
+        return if (step == 0) {
+            0
+        } else {
+            guideBeamMin.value + ((step - 1) * (guideBeamMax.value - guideBeamMin.value) / 9)
+        }
+    }
 
     // Example: Emitting an event after a delay
     fun txPacketLoop() {

docs/change_summary_2026-03-04.md

@@ -0,0 +1,53 @@
+# 변경 요약 (2026-03-04)
+
+이 문서는 현재 `git diff` 기준으로 반영된 변경을 정리합니다.
+
+## 1) 시리얼 초기 전송 누락(Startup race) 대응
+
+### 변경 파일
+- `app/src/main/java/com/laseroptek/raman/ui/MainActivity.kt`
+- `app/src/main/java/com/laseroptek/raman/ui/screens/main/MainViewModel.kt`
+
+### 변경 내용
+- `MainActivity.initialize()`의 시리얼 시작 순서를 조정
+  - 이전: `txPacketOnce()` -> `rxPacketLoop()` -> `txPacketLoop()`
+  - 이후: `rxPacketLoop()` -> `txPacketOnce()` -> `txPacketLoop()`
+- `MainViewModel.txPacketOnce()`를 코루틴(IO)에서 실행하도록 변경
+- `waitUntilSerialReady()` 추가
+  - 최대 2초 동안 20ms 간격으로 `FD != -1` 확인
+  - 준비 실패 시 에러 로그 후 초기 TX 중단
+- 관련 설명 주석 추가
+
+### 의도/효과
+- 앱 시작 직후 `open()` 완료 전 TX가 먼저 발생하는 레이스를 완화/방어
+- 포트 미준비 상태(`FD == -1`)에서 write가 호출되어 초기 패킷이 누락되는 문제를 줄임
+
+## 2) HandPiece 기본값 변경
+
+### 변경 파일
+- `app/src/main/java/com/laseroptek/raman/data/model/serial/HandPiece.kt`
+
+### 변경 내용
+- `HandPiece.type` 기본값 변경
+  - 이전: `1`
+  - 이후: `0`
+
+### 영향 포인트
+- 기본 인스턴스 생성 시 handpiece type의 초기 상태가 달라집니다.
+- 초기 테이블 선택/상태 표시 로직에서 기본 타입 가정이 있다면 함께 점검 필요합니다.
+
+## 3) 문서화
+
+### 추가/수정 파일
+- `docs/serial_tx_startup_race.md` (신규)
+- `README.md` (Troubleshooting 링크 추가)
+
+### 내용
+- FD(File Descriptor) 개념
+- startup race 원인 및 수정 내역
+- 왜 TX에서 직접 open하지 않았는지
+- 확인 포인트
+
+## 4) 참고
+- 현재 요약은 커밋 로그가 아닌 워크트리 `git diff` 기준입니다.
+- 빌드 검증은 `gradlew` CRLF 문제로 로컬 셸에서 미실행 상태입니다.

docs/serial_tx_startup_race.md

@@ -0,0 +1,41 @@
+# Serial TX Startup Race 정리
+
+## 1) FD(File Descriptor)란?
+- `FD`는 리눅스/안드로이드에서 열린 리소스(파일/소켓/시리얼 포트)를 가리키는 정수 핸들입니다.
+- 이 프로젝트에서 시리얼 포트 상태는 다음처럼 판단합니다.
+  - `FD == -1`: 포트 미오픈(유효하지 않음)
+  - `FD >= 0`: 포트 오픈 완료(유효)
+- 따라서 `FD == -1` 상태에서 `write()`를 호출하면 실제 시리얼 전송이 되지 않습니다.
+
+## 2) 문제 원인
+- `txPacketOnce()`가 앱 시작 직후 실행됩니다.
+- 시리얼 포트 `open()`은 `rxPacketLoop()` 내부에서 코루틴으로 비동기 시작됩니다.
+- 기존 순서에서 `txPacketOnce()`가 먼저 호출되면, 포트 오픈 완료 전(`FD == -1`)에 TX가 시도되어 초기 패킷 전송이 누락될 수 있습니다.
+
+## 3) 적용한 수정
+
+### A. 초기 호출 순서 조정
+- 파일: `app/src/main/java/com/laseroptek/raman/ui/MainActivity.kt`
+- 변경:
+  - 이전: `txPacketOnce()` -> `rxPacketLoop()` -> `txPacketLoop()`
+  - 이후: `rxPacketLoop()` -> `txPacketOnce()` -> `txPacketLoop()`
+- 목적: RX 루프가 먼저 포트 오픈을 시작하도록 해서 초기 TX 레이스 확률을 줄임
+
+### B. `txPacketOnce()`에 포트 준비 대기 추가
+- 파일: `app/src/main/java/com/laseroptek/raman/ui/screens/main/MainViewModel.kt`
+- 변경:
+  - `txPacketOnce()`를 IO 코루틴에서 실행
+  - `waitUntilSerialReady()`(최대 2초, 20ms 폴링)로 `FD != -1` 확인 후 TX 진행
+  - 시간 내 준비 실패 시 로그를 남기고 전송 중단
+- 목적: 순서만으로 보장되지 않는 코루틴 스케줄링 레이스를 방어
+
+## 4) 왜 TX에서 직접 open()하지 않았는가?
+- 현재 구조에서 `open()`의 데이터 콜백은 `rxPacketLoop()`의 `callbackFlow`와 연결됩니다.
+- TX 경로에서 별도 `open()`을 하면 중복 오픈/콜백 소유권/FD 교체 타이밍 이슈가 생길 수 있습니다.
+- 안정적인 패턴은:
+  - 포트 오픈 책임: RX(단일 지점)
+  - 포트 사용(TX): ready 확인 후 write
+
+## 5) 확인 포인트
+- 앱 시작 직후 로그에서 `FD`가 유효해진 뒤 `txPacketOnce()`의 TX 로그가 출력되는지 확인
+- 장비 측 시리얼 모니터에서 초기 패킷(Version/Q-Switch/GuideBeam/DCD/SprayDCD) 수신 여부 확인