Add input buffering

README.md

@@ -94,35 +94,6 @@ build/outputs/apk/debug/a3270-debug.apk
 
 ---
 
-## 🏷️ How to Tag & Publish (Beta) Releases
-
-Releases can be published automatically to Gitea via Git tags:
-
-```bash
-# 1. Create a version tag (stable or beta)
-git tag -a v0.1.0-beta.1 -m "Release v0.1.0-beta.1"
-
-# Or a stable release:
-git tag -a v0.1.0 -m "Release v0.1.0"
-
-# 2. Push the tag to Gitea
-git push origin v0.1.0-beta.1
-```
-
-Pushing any `v*` tag triggers the automated release workflow (`.gitea/workflows/release.yaml`), which:
-1. Automatically detects pre-releases (tags containing `beta`, `alpha`, `rc`, `pre`, `preview`, or `dev`) and marks them as **Pre-release** on Gitea.
-2. Builds the APK and packages it.
-3. Publishes a new Gitea Release with `a3270.apk` attached automatically.
-
----
-
-## 🔍 Topics & Discoverability
-
-Suggested keywords/topics for repository indexing:
-`tn3270` · `tn3270e` · `ibm-3270` · `mainframe` · `terminal-emulator` · `android` · `android-app` · `jetpack-compose` · `kotlin` · `x3270` · `j3270` · `ind-file` · `file-transfer` · `ebcdic` · `z-vm` · `z-os` · `cms` · `tso` · `cics`
-
----
-
 ## 🤝 Contributing
 
 Contributions are welcome! Please feel free to open a bug report or feature request via the Gitea issue tracker.

build.gradle

@@ -11,8 +11,8 @@ android {
         applicationId "org.pubvm.a3270"
         minSdk 24
         targetSdk 34
-        versionCode 1
-        versionName "0.1.0"
+        versionCode 2
+        versionName "0.1.1"
     }
 
     buildTypes {

build.sh

@@ -6,11 +6,11 @@ cd "$SCRIPT_DIR"
 
 echo "=== Building a3270 (Android APK) ==="
 
-# Set up JAVA_HOME if not already set
-if [ -z "$JAVA_HOME" ]; then
-    if [ -d "/Users/rudi/.sdkman/candidates/java/21.0.6-sem" ]; then
+# Set up JAVA_HOME (prefer JDK 21 if available)
+if [ -d "/Users/rudi/.sdkman/candidates/java/21.0.6-sem" ]; then
     export JAVA_HOME="/Users/rudi/.sdkman/candidates/java/21.0.6-sem"
-    elif [ -d "/Users/rudi/.sdkman/candidates/java/current" ]; then
+elif [ -z "$JAVA_HOME" ]; then
+    if [ -d "/Users/rudi/.sdkman/candidates/java/current" ]; then
         export JAVA_HOME="/Users/rudi/.sdkman/candidates/java/current"
     fi
 fi
@@ -42,7 +42,7 @@ if [ ! -d "$J3270_PATH/lib3270j" ]; then
 fi
 
 echo "Building debug APK..."
-./gradlew assembleDebug --no-daemon
+./gradlew assembleDebug
 
 APK_PATH="$SCRIPT_DIR/build/outputs/apk/debug/a3270-debug.apk"
 if [ -f "$APK_PATH" ]; then

gradle.properties

@@ -1,2 +1,3 @@
 android.useAndroidX=true
-org.gradle.jvmargs=-Xmx2048m -XX:MaxMetaspaceSize=512m
+org.gradle.jvmargs=-Xmx2048m -XX:+IgnoreUnrecognizedVMOptions -XX:MaxMetaspaceSize=512m
+

src/main/java/org/pubvm/a3270/MainActivity.kt

@@ -34,6 +34,7 @@ import org.pubvm.a3270.service.TerminalService
 import org.pubvm.a3270.storage.HostStorage
 import org.pubvm.a3270.ui.ConnectDialog
 import org.pubvm.a3270.ui.FileTransferDialog
+import org.pubvm.a3270.ui.SettingsDialog
 import org.pubvm.a3270.ui.TwoRowKeyBar
 import org.pubvm.a3270.ui.OiaStatusBar
 import org.pubvm.a3270.ui.TerminalView
@@ -135,6 +136,12 @@ class MainActivity : ComponentActivity() {
                     viewModel.tab()
                 }
                 return true
+            } else if (keyCode == KeyEvent.KEYCODE_DEL) {
+                viewModel.backspace()
+                return true
+            } else if (keyCode == KeyEvent.KEYCODE_ESCAPE) {
+                viewModel.resetKeyboard()
+                return true
             }
         }
         return super.dispatchKeyEvent(event)
@@ -156,9 +163,12 @@ fun MainScreen(
     val oiaText by viewModel.oiaText.collectAsState()
     val isKeyboardLocked by viewModel.isKeyboardLocked.collectAsState()
     val screenVersion by viewModel.screenVersion.collectAsState()
+    val maskHiddenInput by viewModel.maskHiddenInput.collectAsState()
+    val cursorBlink by viewModel.cursorBlink.collectAsState()
 
     var showConnectDialog by remember { mutableStateOf(false) }
     var showFtDialog by remember { mutableStateOf(false) }
+    var showSettingsDialog by remember { mutableStateOf(false) }
 
     val focusRequester = remember { FocusRequester() }
     val keyboardController = LocalSoftwareKeyboardController.current
@@ -213,6 +223,8 @@ fun MainScreen(
                 cols = cols,
                 cursorAddr = cursorAddr,
                 screenVersion = screenVersion,
+                maskHiddenFields = maskHiddenInput,
+                blinkCursor = cursorBlink,
                 onTapAddress = { addr ->
                     viewModel.setCursor(addr)
                     focusRequester.requestFocus()
@@ -230,13 +242,7 @@ fun MainScreen(
                 onValueChange = { newValue ->
                     val text = newValue.text
                     if (text.isNotEmpty()) {
-                        for (ch in text) {
-                            if (ch == '\n' || ch == '\r') {
-                                viewModel.sendAid(AID_ENTER)
-                            } else {
-                                viewModel.typeChar(ch)
-                            }
-                        }
+                        viewModel.typeString(text)
                         textFieldValue = TextFieldValue("")
                         onClearShift()
                     }
@@ -279,6 +285,7 @@ fun MainScreen(
                 onConnectClick = { showConnectDialog = true },
                 onDisconnectClick = { viewModel.disconnect() },
                 onFtClick = { showFtDialog = true },
+                onSettingsClick = { showSettingsDialog = true },
                 onSendAid = { aid ->
                     viewModel.sendAid(aid)
                     focusRequester.requestFocus()
@@ -345,4 +352,17 @@ fun MainScreen(
             }
         )
     }
+
+    if (showSettingsDialog) {
+        SettingsDialog(
+            initialMaskHiddenInput = maskHiddenInput,
+            initialCursorBlink = cursorBlink,
+            onDismiss = { showSettingsDialog = false },
+            onSave = { mask, blink ->
+                showSettingsDialog = false
+                viewModel.updateSettings(mask, blink)
+                focusRequester.requestFocus()
+            }
+        )
+    }
 }

src/main/java/org/pubvm/a3270/TerminalViewModel.kt

@@ -5,6 +5,7 @@ import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.asCoroutineDispatcher
+import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -15,12 +16,28 @@ import org.lib3270j.Telnet3270Client
 import org.lib3270j.TerminalModel
 import org.lib3270j.listener.ConnectionListener
 import org.lib3270j.listener.ScreenUpdateListener
+import org.lib3270j.protocol.DS3270Constants.AID_ENTER
 import org.lib3270j.protocol.DS3270Constants.faIsProtected
 import org.lib3270j.screen.ScreenBuffer
 import org.pubvm.a3270.service.TerminalService
+import org.pubvm.a3270.storage.AppSettings
 import java.util.concurrent.Executors
 import java.util.logging.Logger
 
+sealed interface TerminalInputAction {
+    data class TypeText(val text: String) : TerminalInputAction
+    data class SendAid(val aidCode: Int) : TerminalInputAction
+    data object Backspace : TerminalInputAction
+    data object Tab : TerminalInputAction
+    data object BackTab : TerminalInputAction
+    data object CursorLeft : TerminalInputAction
+    data object CursorRight : TerminalInputAction
+    data object CursorUp : TerminalInputAction
+    data object CursorDown : TerminalInputAction
+    data object Reset : TerminalInputAction
+    data class SetCursor(val baddr: Int) : TerminalInputAction
+}
+
 class TerminalViewModel(application: Application) : AndroidViewModel(application) {
 
     private val log = Logger.getLogger(TerminalViewModel::class.java.name)
@@ -31,6 +48,9 @@ class TerminalViewModel(application: Application) : AndroidViewModel(application
     private val inputExecutor = Executors.newSingleThreadExecutor()
     private val inputDispatcher = inputExecutor.asCoroutineDispatcher()
 
+    // Non-blocking FIFO input channel buffer
+    private val inputChannel = Channel<TerminalInputAction>(Channel.UNLIMITED)
+
     private val _connectionState = MutableStateFlow(ConnectionState.NOT_CONNECTED)
     val connectionState: StateFlow<ConnectionState> = _connectionState.asStateFlow()
 
@@ -55,6 +75,12 @@ class TerminalViewModel(application: Application) : AndroidViewModel(application
     private val _isKeyboardLocked = MutableStateFlow(false)
     val isKeyboardLocked: StateFlow<Boolean> = _isKeyboardLocked.asStateFlow()
 
+    private val _maskHiddenInput = MutableStateFlow(AppSettings.isMaskHiddenInputEnabled(application))
+    val maskHiddenInput: StateFlow<Boolean> = _maskHiddenInput.asStateFlow()
+
+    private val _cursorBlink = MutableStateFlow(AppSettings.isCursorBlinkEnabled(application))
+    val cursorBlink: StateFlow<Boolean> = _cursorBlink.asStateFlow()
+
     private var client: Telnet3270Client? = null
     var currentHost: String = ""
         private set
@@ -62,6 +88,98 @@ class TerminalViewModel(application: Application) : AndroidViewModel(application
     private var lastScreenContentHash: Int = 0
     private var hasInitialScreenLoaded: Boolean = false
 
+    init {
+        // Start continuous background input buffer consumer
+        viewModelScope.launch(inputDispatcher) {
+            for (action in inputChannel) {
+                processInputAction(action)
+                // Drain any additional pending actions in the buffer before updating the UI
+                while (true) {
+                    val next = inputChannel.tryReceive().getOrNull() ?: break
+                    processInputAction(next)
+                }
+                val c = client
+                if (c != null) {
+                    _cursorAddress.value = c.screenBuffer.cursorAddress
+                }
+                _screenVersion.value = System.currentTimeMillis()
+            }
+        }
+    }
+
+    private fun processInputAction(action: TerminalInputAction) {
+        val c = client ?: return
+        val ip = c.inputProcessor
+        val buf = c.screenBuffer
+
+        try {
+            when (action) {
+                is TerminalInputAction.TypeText -> {
+                    ip.isKeyboardLocked = false
+                    for (ch in action.text) {
+                        if (ch == '\n' || ch == '\r') {
+                            ip.setKeyboardLocked(false)
+                            ip.sendAid(AID_ENTER)
+                        } else if (ch >= ' ') {
+                            var curAddr = buf.cursorAddress
+                            if (buf.isFormatted) {
+                                val faVal = buf.getFieldAttributeAt(curAddr)
+                                if (faIsProtected(faVal.toInt() and 0xFF) || buf.getCell(curAddr).isFieldAttribute) {
+                                    curAddr = buf.findNextUnprotected(curAddr)
+                                    buf.cursorAddress = curAddr
+                                }
+                            }
+                            ip.typeCharacter(ch)
+                        }
+                    }
+                }
+                is TerminalInputAction.SendAid -> {
+                    ip.setKeyboardLocked(false)
+                    ip.sendAid(action.aidCode)
+                }
+                is TerminalInputAction.Backspace -> {
+                    ip.isKeyboardLocked = false
+                    ip.backspace()
+                }
+                is TerminalInputAction.Tab -> {
+                    ip.tab()
+                }
+                is TerminalInputAction.BackTab -> {
+                    ip.backTab()
+                }
+                is TerminalInputAction.CursorLeft -> {
+                    ip.cursorLeft()
+                }
+                is TerminalInputAction.CursorRight -> {
+                    ip.cursorRight()
+                }
+                is TerminalInputAction.CursorUp -> {
+                    ip.cursorUp()
+                }
+                is TerminalInputAction.CursorDown -> {
+                    ip.cursorDown()
+                }
+                is TerminalInputAction.Reset -> {
+                    ip.reset()
+                }
+                is TerminalInputAction.SetCursor -> {
+                    if (action.baddr in 0 until (buf.rows * buf.cols)) {
+                        buf.cursorAddress = action.baddr
+                    }
+                }
+            }
+        } catch (e: Exception) {
+            log.warning("Error processing input action: ${e.message}")
+        }
+    }
+
+    fun updateSettings(maskHidden: Boolean, blink: Boolean) {
+        AppSettings.setMaskHiddenInputEnabled(getApplication(), maskHidden)
+        AppSettings.setCursorBlinkEnabled(getApplication(), blink)
+        _maskHiddenInput.value = maskHidden
+        _cursorBlink.value = blink
+    }
+
     fun connect(host: String, port: Int = 23, modelNum: Int = 2, luName: String = "") {
         if (_connectionState.value.isConnected()) return
         currentHost = host
@@ -172,175 +290,59 @@ class TerminalViewModel(application: Application) : AndroidViewModel(application
     }
 
     fun typeChar(ch: Char) {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                val ip = c.inputProcessor
-                ip.isKeyboardLocked = false // Ensure keyboard lock is cleared on user typing
-                val buf = c.screenBuffer
-                var curAddr = buf.cursorAddress
-                if (buf.isFormatted) {
-                    val faVal = buf.getFieldAttributeAt(curAddr)
-                    if (faIsProtected(faVal.toInt() and 0xFF) || buf.getCell(curAddr).isFieldAttribute) {
-                        curAddr = buf.findNextUnprotected(curAddr)
-                        buf.cursorAddress = curAddr
-                    }
-                }
-                ip.typeCharacter(ch)
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error typing char: ${e.message}")
+        inputChannel.trySend(TerminalInputAction.TypeText(ch.toString()))
     }
+
+    fun typeString(text: String) {
+        if (text.isNotEmpty()) {
+            inputChannel.trySend(TerminalInputAction.TypeText(text))
         }
     }
 
     fun pasteString(text: String) {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                val ip = c.inputProcessor
-                ip.isKeyboardLocked = false
-                for (ch in text) {
-                    if (ch == '\n' || ch == '\r') {
-                        ip.tab()
-                    } else if (ch >= ' ') {
-                        ip.typeCharacter(ch)
-                    }
-                }
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error pasting text: ${e.message}")
-            }
+        if (text.isNotEmpty()) {
+            inputChannel.trySend(TerminalInputAction.TypeText(text))
         }
     }
 
     fun backspace() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.isKeyboardLocked = false
-                c.inputProcessor.backspace()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error backspacing: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.Backspace)
     }
 
     fun tab() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.tab()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error tabbing: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.Tab)
     }
 
     fun backTab() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.backTab()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error back-tabbing: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.BackTab)
     }
 
     fun resetKeyboard() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.reset()
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error resetting keyboard: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.Reset)
     }
 
     fun sendAid(aidCode: Int) {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.setKeyboardLocked(false)
-                c.inputProcessor.sendAid(aidCode)
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error sending AID: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.SendAid(aidCode))
     }
 
     fun setCursor(baddr: Int) {
-        val buf = _screenBuffer.value ?: return
-        if (baddr in 0 until (buf.rows * buf.cols)) {
-            buf.cursorAddress = baddr
-            _cursorAddress.value = baddr
-            _screenVersion.value = System.currentTimeMillis()
-        }
+        inputChannel.trySend(TerminalInputAction.SetCursor(baddr))
     }
 
     fun cursorLeft() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.cursorLeft()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error cursorLeft: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.CursorLeft)
     }
 
     fun cursorUp() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.cursorUp()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error cursorUp: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.CursorUp)
     }
 
     fun cursorDown() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.cursorDown()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error cursorDown: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.CursorDown)
     }
 
     fun cursorRight() {
-        val c = client ?: return
-        viewModelScope.launch(inputDispatcher) {
-            try {
-                c.inputProcessor.cursorRight()
-                _cursorAddress.value = c.screenBuffer.cursorAddress
-                _screenVersion.value = System.currentTimeMillis()
-            } catch (e: Exception) {
-                log.warning("Error cursorRight: ${e.message}")
-            }
-        }
+        inputChannel.trySend(TerminalInputAction.CursorRight)
     }
 
     private fun extractScreenSnippet(buf: ScreenBuffer?): String {
@@ -415,6 +417,7 @@ class TerminalViewModel(application: Application) : AndroidViewModel(application
     override fun onCleared() {
         super.onCleared()
         client?.disconnect()
+        inputChannel.close()
         inputExecutor.shutdown()
     }
 }

src/main/java/org/pubvm/a3270/storage/AppSettings.kt

@@ -0,0 +1,30 @@
+package org.pubvm.a3270.storage
+
+import android.content.Context
+import android.content.SharedPreferences
+
+object AppSettings {
+    private const val PREFS_NAME = "a3270_settings"
+    private const val KEY_MASK_HIDDEN_INPUT = "mask_hidden_input"
+    private const val KEY_CURSOR_BLINK = "cursor_blink"
+
+    private fun getPrefs(context: Context): SharedPreferences {
+        return context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+    }
+
+    fun isMaskHiddenInputEnabled(context: Context): Boolean {
+        return getPrefs(context).getBoolean(KEY_MASK_HIDDEN_INPUT, true)
+    }
+
+    fun setMaskHiddenInputEnabled(context: Context, enabled: Boolean) {
+        getPrefs(context).edit().putBoolean(KEY_MASK_HIDDEN_INPUT, enabled).apply()
+    }
+
+    fun isCursorBlinkEnabled(context: Context): Boolean {
+        return getPrefs(context).getBoolean(KEY_CURSOR_BLINK, true)
+    }
+
+    fun setCursorBlinkEnabled(context: Context, enabled: Boolean) {
+        getPrefs(context).edit().putBoolean(KEY_CURSOR_BLINK, enabled).apply()
+    }
+}

src/main/java/org/pubvm/a3270/ui/FunctionKeyBar.kt

@@ -26,6 +26,7 @@ fun TwoRowKeyBar(
     onConnectClick: () -> Unit,
     onDisconnectClick: () -> Unit,
     onFtClick: () -> Unit,
+    onSettingsClick: () -> Unit = {},
     onSendAid: (Int) -> Unit,
     onReset: () -> Unit,
     onTab: () -> Unit,
@@ -51,7 +52,7 @@ fun TwoRowKeyBar(
                 .padding(horizontal = 1.dp, vertical = 1.dp),
             verticalAlignment = Alignment.CenterVertically
         ) {
-            // 1. Menu Dropdown Button (Connect/Disconnect/FT)
+            // 1. Menu Dropdown Button (Connect/Disconnect/FT/Settings)
             Box(modifier = Modifier.weight(1f)) {
                 KeyButton(
                     label = "⋮",
@@ -89,6 +90,13 @@ fun TwoRowKeyBar(
                             }
                         )
                     }
+                    DropdownMenuItem(
+                        text = { Text("Settings", color = Color.White, fontWeight = FontWeight.SemiBold) },
+                        onClick = {
+                            menuExpanded = false
+                            onSettingsClick()
+                        }
+                    )
                 }
             }
 
@@ -178,6 +186,7 @@ fun TwoRowKeyBar(
         }
     }
 }
+
 @Composable
 private fun KeyButton(
     label: String,

src/main/java/org/pubvm/a3270/ui/SettingsDialog.kt

@@ -0,0 +1,132 @@
+package org.pubvm.a3270.ui
+
+import androidx.compose.foundation.layout.*
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.*
+import androidx.compose.runtime.*
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.window.Dialog
+
+@Composable
+fun SettingsDialog(
+    initialMaskHiddenInput: Boolean,
+    initialCursorBlink: Boolean,
+    onDismiss: () -> Unit,
+    onSave: (maskHiddenInput: Boolean, cursorBlink: Boolean) -> Unit
+) {
+    var maskHiddenInput by remember { mutableStateOf(initialMaskHiddenInput) }
+    var cursorBlink by remember { mutableStateOf(initialCursorBlink) }
+
+    Dialog(onDismissRequest = onDismiss) {
+        Card(
+            shape = RoundedCornerShape(12.dp),
+            colors = CardDefaults.cardColors(containerColor = Color(0xFF1E1E1E)),
+            modifier = Modifier
+                .fillMaxWidth()
+                .padding(16.dp)
+        ) {
+            Column(
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .padding(20.dp)
+            ) {
+                Text(
+                    text = "Terminal Settings",
+                    fontSize = 18.sp,
+                    fontWeight = FontWeight.Bold,
+                    color = Color.White
+                )
+
+                Spacer(modifier = Modifier.height(16.dp))
+
+                // Setting 1: Mask Protected/Hidden Input with '*'
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    verticalAlignment = Alignment.CenterVertically,
+                    horizontalArrangement = Arrangement.SpaceBetween
+                ) {
+                    Column(modifier = Modifier.weight(1f).padding(end = 12.dp)) {
+                        Text(
+                            text = "Show '*' for Hidden Fields",
+                            fontSize = 14.sp,
+                            fontWeight = FontWeight.SemiBold,
+                            color = Color.White
+                        )
+                        Text(
+                            text = "Display asterisks for typed characters in non-display / password fields rather than blank spaces.",
+                            fontSize = 12.sp,
+                            color = Color.LightGray
+                        )
+                    }
+                    Switch(
+                        checked = maskHiddenInput,
+                        onCheckedChange = { maskHiddenInput = it },
+                        colors = SwitchDefaults.colors(
+                            checkedThumbColor = Color.White,
+                            checkedTrackColor = Color(0xFF2B8A3E)
+                        )
+                    )
+                }
+
+                Spacer(modifier = Modifier.height(16.dp))
+                HorizontalDivider(color = Color(0xFF2C2D30))
+                Spacer(modifier = Modifier.height(16.dp))
+
+                // Setting 2: Blinking Cursor
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    verticalAlignment = Alignment.CenterVertically,
+                    horizontalArrangement = Arrangement.SpaceBetween
+                ) {
+                    Column(modifier = Modifier.weight(1f).padding(end = 12.dp)) {
+                        Text(
+                            text = "Blinking Cursor",
+                            fontSize = 14.sp,
+                            fontWeight = FontWeight.SemiBold,
+                            color = Color.White
+                        )
+                        Text(
+                            text = "Blink the terminal cursor to clearly indicate current screen position.",
+                            fontSize = 12.sp,
+                            color = Color.LightGray
+                        )
+                    }
+                    Switch(
+                        checked = cursorBlink,
+                        onCheckedChange = { cursorBlink = it },
+                        colors = SwitchDefaults.colors(
+                            checkedThumbColor = Color.White,
+                            checkedTrackColor = Color(0xFF2B8A3E)
+                        )
+                    )
+                }
+
+                Spacer(modifier = Modifier.height(24.dp))
+
+                // Action Buttons
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.End
+                ) {
+                    TextButton(onClick = onDismiss) {
+                        Text("Cancel", color = Color.LightGray)
+                    }
+                    Spacer(modifier = Modifier.width(8.dp))
+                    Button(
+                        onClick = {
+                            onSave(maskHiddenInput, cursorBlink)
+                        },
+                        colors = ButtonDefaults.buttonColors(containerColor = Color(0xFF2B8A3E))
+                    ) {
+                        Text("Save", color = Color.White)
+                    }
+                }
+            }
+        }
+    }
+}

src/main/java/org/pubvm/a3270/ui/TerminalView.kt

@@ -24,6 +24,7 @@ import androidx.compose.ui.platform.LocalDensity
 import androidx.compose.ui.text.AnnotatedString
 import androidx.compose.ui.unit.DpOffset
 import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
 import org.lib3270j.protocol.DS3270Constants.*
 import org.lib3270j.screen.ExtendedAttribute
 import org.lib3270j.screen.ScreenBuffer
@@ -57,6 +58,8 @@ fun TerminalView(
     cols: Int,
     cursorAddr: Int,
     screenVersion: Long,
+    maskHiddenFields: Boolean = true,
+    blinkCursor: Boolean = true,
     onTapAddress: (Int) -> Unit,
     onPasteText: (String) -> Unit = {},
     modifier: Modifier = Modifier
@@ -70,6 +73,20 @@ fun TerminalView(
     var showContextMenu by remember { mutableStateOf(false) }
     var contextMenuOffset by remember { mutableStateOf(Offset.Zero) }
 
+    // Blinking cursor state (~530ms interval matching j3270)
+    var cursorVisible by remember { mutableStateOf(true) }
+    LaunchedEffect(cursorAddr, blinkCursor) {
+        if (!blinkCursor) {
+            cursorVisible = true
+            return@LaunchedEffect
+        }
+        cursorVisible = true
+        while (true) {
+            delay(530L)
+            cursorVisible = !cursorVisible
+        }
+    }
+
     Box(modifier = modifier.fillMaxSize()) {
         Canvas(
             modifier = Modifier
@@ -213,9 +230,19 @@ fun TerminalView(
                             isBold = true
                         }
 
-                        // Invisible fields (passwords / hidden)
+                        // Invisible fields (passwords / hidden inputs)
                         if (faIsZero(currentFA.toInt() and 0xFF)) {
-                            continue
+                            if (maskHiddenFields && ea.ucs4 > ' ' && ea.ucs4.code != 0xFFFF) {
+                                charVal = '*'
+                            } else {
+                                // Blanks out character
+                                charVal = ' '
+                            }
+                        } else {
+                            // Normal visible character
+                            if (ea.ucs4 > ' ' && ea.ucs4.code != 0xFFFF) {
+                                charVal = ea.ucs4
+                            }
                         }
 
                         // Extended Graphic Rendition
@@ -226,10 +253,6 @@ fun TerminalView(
                             if ((grVal and GR_UNDERLINE) != 0) isUnderline = true
                             if ((grVal and GR_REVERSE) != 0) isReverse = true
                         }
-
-                        if (ea.ucs4 > ' ' && ea.ucs4.code != 0xFFFF) {
-                            charVal = ea.ucs4
-                        }
                     } else {
                         fgColor = HOST_COLORS[HOST_COLOR_GREEN]
                     }
@@ -258,7 +281,8 @@ fun TerminalView(
                         )
                     }
 
-                    if (addr == cursorAddr && !isSelected) {
+                    // Cursor indicator (respects blinking toggle & timer)
+                    if (addr == cursorAddr && !isSelected && cursorVisible) {
                         drawRect(
                             color = HOST_COLORS[HOST_COLOR_TURQUOISE].copy(alpha = 0.5f),
                             topLeft = Offset(left, top),