Initial attempt at serial port support.

Add tvos build

.gitlab-ci.yml

@@ -58,6 +58,10 @@ include:
   - project: 'libretro-infrastructure/ci-templates'
     file: '/ios-arm64.yml'
 
+  # tvOS
+  - project: 'libretro-infrastructure/ci-templates'
+    file: '/tvos-arm64.yml'
+
   ################################## CONSOLES ################################
   # Dingux (GCW Zero)
   - project: 'libretro-infrastructure/ci-templates'
@@ -192,6 +196,12 @@ libretro-build-ios-arm64:
     - .libretro-ios-arm64-make-default
     - .core-defs
 
+# tvOS
+libretro-build-tvos-arm64:
+  extends:
+    - .libretro-tvos-arm64-make-default
+    - .core-defs
+
 ################################### CONSOLES #################################
 # Dingux (GCW Zero)
 libretro-build-dingux-mips32:

CMakeLists.txt

@@ -17,6 +17,10 @@ message("that you are resting well.")
 message(" -- Your friend, Stephanie")
 message("******************************")
 
+if(CMAKE_BUILD_TYPE STREQUAL "Debug")
+	add_compile_definitions(EMU_DEBUG=1)
+endif()
+
 # Main project sources
 add_subdirectory(src)
 

include/dbvzRegisterAccessors.c.h

@@ -710,6 +710,7 @@ static void setUstcnt2(uint16_t value){
 
    registerArrayWrite16(USTCNT2, value);
    updateUart2Interrupt();
+   updateUart2PortState();
 }
 
 static void setTstat1(uint16_t value){

include/dbvzTiming.c.h

@@ -404,6 +404,9 @@ static void dbvzEndClk32(void){
    updateUart1Interrupt();
    updateUart2Interrupt();
 
+   updateUart1PortState();
+   updateUart2PortState();
+
    checkInterrupts();
 }
 

include/emulator.h

@@ -45,13 +45,15 @@ static void debugLog(char* str, ...){};
 //config options
 #define EMU_FPS 60
 #define DBVZ_SYSCLK_PRECISION 2000000//the amount of cycles to run before adding SYSCLKs, higher = faster, higher values may skip timer events and lower audio accuracy
+
 #define AUDIO_SAMPLE_RATE 48000
+#define AUDIO_SAMPLES_PER_FRAME (AUDIO_SAMPLE_RATE / EMU_FPS)
+
 #define AUDIO_SPEAKER_RANGE 0x6000//prevent hitting the top or bottom of the speaker when switching direction rapidly
 #define SD_CARD_NCR_BYTES 1//how many 0xFF bytes come before the R1 response
 #define SAVE_STATE_VERSION 0x00000001
 
 //shared constants
-#define AUDIO_SAMPLES_PER_FRAME (AUDIO_SAMPLE_RATE / EMU_FPS)
 #define SD_CARD_BLOCK_SIZE 512//all newer SDSC cards have this fixed at 512
 #define SD_CARD_BLOCK_DATA_PACKET_SIZE (1 + SD_CARD_BLOCK_SIZE + 2)
 #define SD_CARD_RESPONSE_FIFO_SIZE (SD_CARD_BLOCK_DATA_PACKET_SIZE * 3)
@@ -107,7 +109,7 @@ enum{
 };
 
 //types
-typedef struct{
+typedef struct {
    bool     enable;
    bool     enableParity;
    bool     oddParity;
@@ -213,7 +215,11 @@ extern void      (*palmSerialDataFlush)(void);//called by the emulator to delete
 extern void      (*palmGetRtcFromHost)(uint8_t* writeBack);//[0] = hours, [1] = minutes, [2] = seconds
 
 //functions
-uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t* palmRomData, uint32_t palmRomSize, uint8_t* palmBootloaderData, uint32_t palmBootloaderSize, bool syncRtc, bool allowInvalidBehavior);
+uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t *palmRomData,
+                      uint32_t palmRomSize, uint8_t *palmBootloaderData,
+                      uint32_t palmBootloaderSize, bool syncRtc,
+                      bool allowInvalidBehavior, const char *serialPortDev);
+
 void emulatorDeinit(void);
 void emulatorHardReset(void);
 void emulatorSoftReset(void);

include/serial.h

@@ -0,0 +1,18 @@
+//
+// Created by stephanie on 6/14/24.
+//
+
+#ifndef MU_SERIAL_H
+#define MU_SERIAL_H
+
+#include "emulator.h"
+
+/**
+ * Opens and initializes the serial port.
+ *
+ * @param path The path of the serial port.
+ * @since 2024/06/14
+ */
+void mu_serial_open_and_init(const char* path);
+
+#endif // MU_SERIAL_H

libretroBuildSystem/CMakeLists.txt

@@ -14,6 +14,10 @@ add_library(mu_libretro SHARED
 # Remove the "lib" prefix always, RetroArch does not name in this way
 set_target_properties(mu_libretro PROPERTIES PREFIX "")
 
+# Define these
+target_compile_definitions(mu_libretro PUBLIC
+	__LIBRETRO__=1)
+
 # Bring all the sub-modules as needed
 target_link_libraries(mu_libretro
 	MuCore)
@@ -32,6 +36,11 @@ if(CMAKE_SYSTEM_NAME STREQUAL Windows)
 		set(MU_LIBRETRO_DIR "$ENV{APPDATA}/RetroArch")
 	endif()
 else()
+	find_program(RETROARCH_APP retroarch)
+	if(RETROARCH_APP)
+		get_filename_component(MU_LIBRETRO_DIR "${RETROARCH_APP}" DIRECTORY)
+	endif()
+
 	set(MU_LIBRETRO_EXTENSION "")
 endif()
 

libretroBuildSystem/Makefile.libretro

@@ -186,6 +186,8 @@ else ifeq ($(platform), tvos-arm64)
 ifeq ($(IOSSDK),)
    IOSSDK := $(shell xcodebuild -version -sdk appletvos Path)
 endif
+   CC = clang -arch arm64 -isysroot $(IOSSDK)
+   CXX = clang++ -arch arm64 -isysroot $(IOSSDK)
 
 # Theos iOS
 else ifeq ($(platform), theos_ios)
@@ -391,7 +393,9 @@ else ifneq (,$(findstring armv,$(platform)))
 # Emscripten
 else ifeq ($(platform), emscripten)
 	TARGET := $(TARGET_NAME)_libretro_emscripten.bc
+	AR=emar
 	STATIC_LINKING = 1
+	STATIC_LINKING_LINK = 1
 
 # GCW0
 else ifeq ($(platform), gcw0)
@@ -535,9 +539,7 @@ all: $(TARGET)
 
 $(TARGET): $(OBJECTS)
 	@echo "** BUILDING $(TARGET) FOR PLATFORM $(platform) **"
-ifeq ($(platform), emscripten)
-	$(CC) $(CFLAGS) $(OBJOUT)$@ $^
-else ifeq ($(STATIC_LINKING_LINK), 1)
+ifeq ($(STATIC_LINKING_LINK), 1)
 ifneq (,$(findstring msvc,$(platform)))
 	$(LD) $(LINKOUT)$@ $(OBJECTS)
 else

qtBuildSystem/Mu/Mu.pro

@@ -221,6 +221,7 @@ SOURCES += \
     ../../src/audio/blip_buf.c \
     ../../src/dbvz.c \
     ../../src/emulator.c \
+    ../../src/serial.c \
     ../../src/fileLauncher/launcher.c \
     ../../src/flx68000.c \
     ../../src/m5XXBus.c \

qtBuildSystem/Mu/emuwrapper.h

@@ -54,7 +54,9 @@ public:
    EmuWrapper();
    ~EmuWrapper();
 
-   uint32_t init(const QString& assetPath, const QString& osVersion, bool syncRtc = false, bool allowInvalidBehavior = false, bool fastBoot = false);
+   uint32_t init(const QString &assetPath, const QString &osVersion,
+                 bool syncRtc = false, bool allowInvalidBehavior = false,
+                 bool fastBoot = false, const QString &serialPortDev = "");
    void exit();
    void pause();
    void resume();

qtBuildSystem/Mu/mainwindow.cpp

@@ -47,6 +47,7 @@ MainWindow::MainWindow(QWidget* parent) :
    stateManager = new StateManager(this);
    emuDebugger = new DebugViewer(this);
    refreshDisplay = new QTimer(this);
+
    audioDevice = new QAudioOutput(format, this);
    audioOut = audioDevice->start();
 
@@ -226,7 +227,10 @@ void MainWindow::updateDisplay(){
       ui->display->repaint();
 
       //audio
-      audioOut->write((const char*)emu.getAudioSamples(), AUDIO_SAMPLES_PER_FRAME * 2/*channels*/ * sizeof(int16_t));
+      if (audioOut != NULL) {
+        audioOut->write((const char*)emu.getAudioSamples(),
+          AUDIO_SAMPLES_PER_FRAME * 2/*channels*/ * sizeof(int16_t));
+      }
 
       //power LED
       ui->powerButtonLed->setStyleSheet(emu.getPowerButtonLed() ? "background: lime" : "");
@@ -329,7 +333,14 @@ void MainWindow::on_center_released(){
 void MainWindow::on_ctrlBtn_clicked(){
    if(!emu.isInited()){
       QString sysDir = settings->value("resourceDirectory", "").toString();
-      uint32_t error = emu.init(sysDir, settings->value("palmOsVersionString", "Palm m515/Palm OS 4.1").toString(), settings->value("featureSyncedRtc", false).toBool(), settings->value("featureDurable", false).toBool(), settings->value("fastBoot", false).toBool());
+      uint32_t error = emu.init(
+          sysDir,
+          settings->value("palmOsVersionString", "Palm m515/Palm OS 4.1")
+              .toString(),
+          settings->value("featureSyncedRtc", false).toBool(),
+          settings->value("featureDurable", false).toBool(),
+          settings->value("fastBoot", false).toBool(),
+          settings->value("serialPortDev", "").toString());
 
       if(error == EMU_ERROR_NONE){
          emu.setCpuSpeed(settings->value("cpuSpeed", 1.00).toDouble());

qtBuildSystem/Mu/settingsmanager.cpp

@@ -31,6 +31,10 @@ SettingsManager::SettingsManager(QWidget* parent) :
    ui->featureSyncedRtc->setChecked(settings->value("featureSyncedRtc", false).toBool());
    ui->featureDurable->setChecked(settings->value("featureDurable", false).toBool());
 
+   ui->serialPortDev->setText(settings->value("serialPortDev",
+      "").toString());
+   connect(ui->serialPortDev, &QLineEdit::textChanged, this, &SettingsManager::on_serialPortDev_textChanged);
+
    setKeySelectorState(-1);
    updateButtonKeys();
 }
@@ -166,3 +170,7 @@ void SettingsManager::on_palmOsVersion_currentIndexChanged(int index){
    settings->setValue("palmOsVersionIndex", index);
    settings->setValue("palmOsVersionString", ui->palmOsVersion->itemText(index));
 }
+
+void SettingsManager::on_serialPortDev_textChanged(const QString& arg1) {
+  settings->setValue("serialPortDev", ui->serialPortDev->text());
+}

qtBuildSystem/Mu/settingsmanager.h

@@ -51,6 +51,8 @@ private slots:
    void on_cpuSpeed_valueChanged(double arg1);
    void on_palmOsVersion_currentIndexChanged(int index);
 
+   void on_serialPortDev_textChanged(const QString& arg1);
+
 private:
    Ui::SettingsManager* ui;
    QSettings*           settings;

qtBuildSystem/Mu/settingsmanager.ui

@@ -29,9 +29,9 @@
       <property name="geometry">
        <rect>
         <x>0</x>
-        <y>0</y>
+        <y>-284</y>
         <width>613</width>
-        <height>444</height>
+        <height>705</height>
        </rect>
       </property>
       <layout class="QVBoxLayout" name="verticalLayout_3">
@@ -430,6 +430,16 @@
          </layout>
         </widget>
        </item>
+       <item>
+        <widget class="QLabel" name="serialPortDevLabel">
+         <property name="text">
+          <string>Serial Port Device</string>
+         </property>
+        </widget>
+       </item>
+       <item>
+        <widget class="QLineEdit" name="serialPortDev"/>
+       </item>
        <item>
         <spacer name="verticalSpacer">
          <property name="orientation">

src/CMakeLists.txt

@@ -3,6 +3,7 @@ add_library(MuCore STATIC
 	ads7846.c
 	dbvz.c
 	emulator.c
+	serial.c
 	flx68000.c
 	m5XXBus.c
 	pdiUsbD12.c

src/dbvz.c

@@ -475,17 +475,26 @@ uint8_t dbvzGetRegister8(uint32_t address){
          //PDSEL lacks the bottom 4 bits but that is handled on write
          return registerArrayRead8(address);
 
+      case URX1:
+      case URX1 + 1:
+      case URX2:
+      case URX2 + 1:
+        return registerArrayRead16(address);
+
       default:
+        printHwRegAccess(address, 0, 8, false);
+
          //bootloader
          if(address >= 0xE00)
             return registerArrayRead8(address);
 
-         printHwRegAccess(address, 0, 8, false);
          return 0x00;
    }
 }
 
 uint16_t dbvzGetRegister16(uint32_t address){
+  uint16_t bit;
+
 #if !defined(EMU_NO_SAFETY)
    if((address & 0x0000F000) != 0x0000F000){
       dbvzSetBusErrorTimeOut(address, false);
@@ -520,6 +529,16 @@ uint16_t dbvzGetRegister16(uint32_t address){
          }
 
       case UTX1:{
+#if defined(EMU_DEBUG)
+            printHwRegAccess(address, 0, 16, false);
+#endif
+            uint16_t dataFlag = 0;
+            if (palmIrDataSize != NULL)
+              if (palmIrDataSize() > 0) {
+                dataFlag = 0x4000;  // byte swapped
+                updateUart1Interrupt();
+              }
+
             uint16_t uart1TxStatus = registerArrayRead16(UTX1);
             uint8_t entrys = uart1TxFifoEntrys();
 
@@ -527,10 +546,20 @@ uint16_t dbvzGetRegister16(uint32_t address){
             uart1TxStatus |= (entrys < 4) << 14;
             uart1TxStatus |= (entrys < 8) << 13;
 
-            return uart1TxStatus;
+            return uart1TxStatus | dataFlag;
          }
 
       case UTX2:{
+#if defined(EMU_DEBUG)
+            printHwRegAccess(address, 0, 16, false);
+#endif
+            uint16_t dataFlag = 0;
+            if (palmSerialDataSize != NULL)
+              if (palmSerialDataSize() > 0) {
+                dataFlag = 0x4000;  // byte swapped
+                updateUart2Interrupt();
+              }
+
             uint16_t uart2TxStatus = registerArrayRead16(UTX2);
             uint8_t entrys = uart2TxFifoEntrys();
 
@@ -538,7 +567,7 @@ uint16_t dbvzGetRegister16(uint32_t address){
             uart2TxStatus |= (entrys < 4) << 14;
             uart2TxStatus |= (entrys < 8) << 13;
 
-            return uart2TxStatus;
+            return uart2TxStatus | dataFlag;
          }
 
       case PLLFSR:
@@ -599,11 +628,12 @@ uint16_t dbvzGetRegister16(uint32_t address){
          return registerArrayRead16(address);
 
       default:
+         printHwRegAccess(address, 0, 16, false);
+
          //bootloader
          if(address >= 0xE00)
             return registerArrayRead16(address);
 
-         printHwRegAccess(address, 0, 16, false);
          return 0x0000;
    }
 }
@@ -668,6 +698,7 @@ void dbvzSetRegister8(uint32_t address, uint8_t value){
          if((registerArrayRead16(USTCNT2) & 0xA000) == 0xA000){
             uart2TxFifoWrite(value);
             updateUart2Interrupt();
+            updateUart2PortState();
          }
          return;
 
@@ -1128,6 +1159,7 @@ void dbvzSetRegister16(uint32_t address, uint16_t value){
          if((registerArrayRead16(USTCNT2) & 0xA000) == 0xA000){
             uart2TxFifoWrite(value & 0x1000 ? value & 0xFF : EMU_SERIAL_BREAK);
             updateUart2Interrupt();
+            updateUart2PortState();
          }
          return;
 

src/emulator.c

@@ -11,6 +11,7 @@
 #include "ads7846.h"
 #include "pdiUsbD12.h"
 #include "sdCard.h"
+#include "serial.h"
 #include "silkscreen.h"
 #include "portability.h"
 #if defined(EMU_SUPPORT_PALM_OS5)
@@ -99,8 +100,28 @@ static void patchOsRom(uint32_t address, char* patch){
       swap16BufferIfLittle(&palmRom[swapBegin], swapSize);
 }
 
+/**
+ * Fills the initial RAM with garbage.
+ *
+ * @param ram The RAM to fill.
+ * @param size The size of RAM.
+ * @since 2024/06/14
+ */
+void mu_garbage_fill(uint8_t* ram, uint32_t size) {
+  uint32_t i;
+  uint8_t vis;
 
-uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t* palmRomData, uint32_t palmRomSize, uint8_t* palmBootloaderData, uint32_t palmBootloaderSize, bool syncRtc, bool allowInvalidBehavior){
+  vis = 179;
+  for (i = 0; i < size; i++) {
+    ram[i] = vis;
+    vis = ((vis << 1) | ((vis >> 7) & 1)) ^ 0xFF;
+  }
+}
+
+uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t *palmRomData,
+                      uint32_t palmRomSize, uint8_t *palmBootloaderData,
+                      uint32_t palmBootloaderSize, bool syncRtc,
+                      bool allowInvalidBehavior, const char *serialPortDev) {
    if(emulatorInitialized)
       return EMU_ERROR_RESOURCE_LOCKED;
 
@@ -115,13 +136,19 @@ uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t* palmRomData, uint32_t pal
    palmIrDataReceive = NULL;
    palmIrDataSend = NULL;
    palmIrDataFlush = NULL;
-   palmSerialSetPortProperties = NULL;
-   palmSerialDataSize = NULL;
-   palmSerialDataReceive = NULL;
-   palmSerialDataSend = NULL;
-   palmSerialDataFlush = NULL;
    palmGetRtcFromHost = NULL;
 
+  // Setup serial port
+  palmSerialSetPortProperties = NULL;
+  palmSerialDataSize = NULL;
+  palmSerialDataReceive = NULL;
+  palmSerialDataSend = NULL;
+  palmSerialDataFlush = NULL;
+
+  if (serialPortDev != NULL) {
+    mu_serial_open_and_init(serialPortDev);
+  }
+
 #if defined(EMU_SUPPORT_PALM_OS5)
    palmEmulatingTungstenT3 = emulatedDevice == EMU_DEVICE_TUNGSTEN_T3;
 
@@ -173,7 +200,9 @@ uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t* palmRomData, uint32_t pal
 
       //allocate buffers, add 4 to memory regions to prevent SIGSEGV from accessing off the end
       palmRom = malloc(M5XX_ROM_SIZE + 4);
-      palmRam = malloc((palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE) + 4);
+
+      palmRam = malloc((emulatorGetRamSize()) + 4);
+
       palmFramebuffer = malloc(160 * 220 * sizeof(uint16_t));
       palmAudio = malloc(AUDIO_SAMPLES_PER_FRAME * 2 * sizeof(int16_t));
       palmAudioResampler = blip_new(AUDIO_SAMPLE_RATE);//have 1 second of samples
@@ -191,7 +220,10 @@ uint32_t emulatorInit(uint8_t emulatedDevice, uint8_t* palmRomData, uint32_t pal
       if(palmRomSize < M5XX_ROM_SIZE)
          memset(palmRom + palmRomSize, 0x00, M5XX_ROM_SIZE - palmRomSize);
       swap16BufferIfLittle(palmRom, M5XX_ROM_SIZE / sizeof(uint16_t));
-      memset(palmRam, 0x00, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
+
+      memset(palmRam, 0x00, emulatorGetRamSize());
+      mu_garbage_fill(palmRam, emulatorGetRamSize());
+
       dbvzLoadBootloader(palmBootloaderData, palmBootloaderSize);
       memcpy(palmFramebuffer + 160 * 160, silkscreen160x60, 160 * 60 * sizeof(uint16_t));
       memset(palmAudio, 0x00, AUDIO_SAMPLES_PER_FRAME * 2/*channels*/ * sizeof(int16_t));
@@ -262,7 +294,7 @@ void emulatorHardReset(void){
    }
    else{
 #endif
-      memset(palmRam, 0x00, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
+      memset(palmRam, 0x00, emulatorGetRamSize());
       emulatorSoftReset();
       sdCardReset();
       dbvzSetRtc(0, 0, 0, 0);
@@ -330,7 +362,7 @@ uint32_t emulatorGetStateSize(void){
          size += sed1376StateSize();
       size += ads7846StateSize();
       size += pdiUsbD12StateSize();
-      size += palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE;//system RAM buffer
+      size += emulatorGetRamSize();//system RAM buffer
 #if defined(EMU_SUPPORT_PALM_OS5)
    }
 #endif
@@ -402,9 +434,9 @@ bool emulatorSaveState(uint8_t* data, uint32_t size){
       offset += pdiUsbD12StateSize();
 
       //memory
-      memcpy(data + offset, palmRam, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
-      swap16BufferIfLittle(data + offset, (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE) / sizeof(uint16_t));
-      offset += palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE;
+      memcpy(data + offset, palmRam, emulatorGetRamSize());
+      swap16BufferIfLittle(data + offset, (emulatorGetRamSize()) / sizeof(uint16_t));
+      offset += emulatorGetRamSize();
 #if defined(EMU_SUPPORT_PALM_OS5)
    }
 #endif
@@ -526,9 +558,9 @@ bool emulatorLoadState(uint8_t* data, uint32_t size){
       offset += pdiUsbD12StateSize();
 
       //memory
-      memcpy(palmRam, data + offset, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
-      swap16BufferIfLittle(palmRam, (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE) / sizeof(uint16_t));
-      offset += palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE;
+      memcpy(palmRam, data + offset, emulatorGetRamSize());
+      swap16BufferIfLittle(palmRam, (emulatorGetRamSize()) / sizeof(uint16_t));
+      offset += emulatorGetRamSize();
 #if defined(EMU_SUPPORT_PALM_OS5)
    }
 #endif
@@ -608,7 +640,9 @@ uint32_t emulatorGetRamSize(void){
    if(palmEmulatingTungstenT3)
       return TUNGSTEN_T3_RAM_SIZE;
 #endif
-   return palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE;
+   if (palmEmulatingM500)
+      return M500_RAM_SIZE;
+   return M515_RAM_SIZE;
 }
 
 bool emulatorSaveRam(uint8_t* data, uint32_t size){
@@ -621,11 +655,11 @@ bool emulatorSaveRam(uint8_t* data, uint32_t size){
    }
    else{
 #endif
-      if(size < (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE))
+      if(size < (emulatorGetRamSize()))
          return false;
 
-      memcpy(data, palmRam, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
-      swap16BufferIfLittle(data, (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE) / sizeof(uint16_t));
+      memcpy(data, palmRam, emulatorGetRamSize());
+      swap16BufferIfLittle(data, (emulatorGetRamSize()) / sizeof(uint16_t));
 #if defined(EMU_SUPPORT_PALM_OS5)
    }
 #endif
@@ -643,11 +677,11 @@ bool emulatorLoadRam(uint8_t* data, uint32_t size){
    }
    else{
 #endif
-      if(size < (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE))
+      if(size < (emulatorGetRamSize()))
          return false;
 
-      memcpy(palmRam, data, palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE);
-      swap16BufferIfLittle(palmRam, (palmEmulatingM500 ? M500_RAM_SIZE : M515_RAM_SIZE) / sizeof(uint16_t));
+      memcpy(palmRam, data, emulatorGetRamSize());
+      swap16BufferIfLittle(palmRam, (emulatorGetRamSize()) / sizeof(uint16_t));
 #if defined(EMU_SUPPORT_PALM_OS5)
    }
 #endif

src/makefile.all

@@ -1,5 +1,6 @@
 EMU_DEFINES :=
 EMU_SOURCES_C := $(EMU_PATH)/emulator.c \
+    $(EMU_PATH)/serial.c \
 	$(EMU_PATH)/m5XXBus.c \
 	$(EMU_PATH)/dbvz.c \
 	$(EMU_PATH)/flx68000.c \

src/serial.c

@@ -0,0 +1,255 @@
+//
+// Created by stephanie on 6/14/24.
+//
+
+#include <stdio.h>
+#include <string.h>
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+  #include <windows.h>
+#else
+  #include <errno.h>
+  #include <fcntl.h>
+  #include <termios.h>
+  #include <unistd.h>
+#endif
+
+#include "emulator.h"
+
+#define MU_SERIAL_DEBUG
+
+#define MU_SERIAL_BUF_SIZE 4096
+
+static const char* mu_serial_path = NULL;
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+static int mu_serial_fd = -1;
+#endif
+
+static uint8_t mu_serial_buf[MU_SERIAL_BUF_SIZE];
+static int32_t mu_serial_buf_len;
+static serial_port_properties_t mu_serial_properties;
+
+void mu_serial_palmSerialSetPortProperties(serial_port_properties_t* properties)
+{
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  struct termios tty;
+#endif
+
+  // Always use base properties
+  if (properties == NULL) {
+    properties = &mu_serial_properties;
+  }
+
+  // Did the properties not actually change?
+  if (0 == memcmp(properties, &mu_serial_properties,
+    sizeof(mu_serial_properties))) {
+    return;
+  }
+
+#if defined(MU_SERIAL_DEBUG)
+  // Debug
+  fprintf(stderr, "Serial PROPERTIES\n");
+#endif
+
+  // Write over new properties
+  memmove(&mu_serial_properties, properties,
+    sizeof(mu_serial_properties));
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  if (properties->enable && mu_serial_fd < 0) {
+#if defined(MU_SERIAL_DEBUG)
+    // Debug
+    fprintf(stderr, "Serial OPEN %s\n", mu_serial_path);
+#endif
+
+    mu_serial_fd = open(mu_serial_path,
+      O_RDWR | O_EXCL | O_NONBLOCK);
+
+    if (mu_serial_fd < 0) {
+      fprintf(stderr, "Serial FAIL %s\n",
+        strerror(errno));
+
+      return;
+    }
+
+    mu_serial_buf_len = 0;
+  } else if (!properties->enable && mu_serial_fd >= 0) {
+#if defined(MU_SERIAL_DEBUG)
+    // Debug
+    fprintf(stderr, "Serial CLOSE %s\n", mu_serial_path);
+#endif
+
+    close(mu_serial_fd);
+
+    mu_serial_fd = -1;
+    mu_serial_buf_len = 0;
+  }
+
+  if (mu_serial_fd >= 0) {
+    memset(&tty, 0, sizeof(tty));
+
+    cfsetspeed(&tty, properties->baudRate);
+
+    if (properties->enableParity) {
+      tty.c_cflag |= PARENB;
+    }
+
+    if (properties->oddParity) {
+      tty.c_cflag |= PARODD;
+    }
+
+    if (properties->stopBits > 1) {
+      tty.c_cflag |= CSTOPB;
+    } else {
+      tty.c_cflag &= (~CSTOPB);
+    }
+
+    if (properties->use8BitMode) {
+      tty.c_cflag |= CS8;
+    } else {
+      tty.c_lflag &= (~CSIZE);
+      tty.c_cflag |= CS7;
+    }
+  }
+#endif
+}
+
+uint32_t mu_serial_palmSerialDataSize(void)
+{
+  int32_t read_count;
+
+  // Do not read any more data if there is any
+  if (mu_serial_buf_len > 0) {
+    return mu_serial_buf_len;
+  }
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  if (mu_serial_fd >= 0) {
+    // Try reading in as much as possible
+    if (mu_serial_buf_len < MU_SERIAL_BUF_SIZE) {
+      read_count = read(mu_serial_fd,
+        &mu_serial_buf[mu_serial_buf_len],
+        MU_SERIAL_BUF_SIZE - mu_serial_buf_len);
+
+      if (read_count > 0) {
+        mu_serial_buf_len += read_count;
+
+#if defined(MU_SERIAL_DEBUG)
+        // Debug
+        fprintf(stderr, "Serial FLOW %d < %d\n",
+          mu_serial_buf_len, read_count);
+#endif
+      }
+    }
+  }
+#endif
+
+  return mu_serial_buf_len;
+}
+
+uint16_t mu_serial_palmSerialDataReceive(void)
+{
+  uint8_t data;
+  uint32_t buf_len;
+
+  // Get size of current buffer
+  buf_len = mu_serial_palmSerialDataSize();
+
+#if defined(MU_SERIAL_DEBUG)
+  // Debug
+  fprintf(stderr, "Serial RECV TRY %d\n", mu_serial_buf_len);
+#endif
+
+  // No data to read?
+  if (buf_len == 0 || mu_serial_buf_len == 0) {
+    return 0;
+  }
+
+  // Read in next byte
+  data = mu_serial_buf[0];
+
+  // Shift over
+  memmove(&mu_serial_buf[0], &mu_serial_buf[1],
+    mu_serial_buf_len - 1);
+  mu_serial_buf_len -= 1;
+
+#if defined(MU_SERIAL_DEBUG)
+  // Debug
+  fprintf(stderr, "Serial RECV %02x %c\n", data, data);
+#endif
+
+  // Give the byte we read
+  return data;
+}
+
+void mu_serial_palmSerialDataSend(uint16_t data)
+{
+  uint8_t part;
+
+  // Only need to send the lower bit
+  part = data & 0xFF;
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  if (mu_serial_fd >= 0) {
+#if defined(MU_SERIAL_DEBUG)
+    // Debug
+    fprintf(stderr, "Serial SEND %02x %c\n", part, part);
+#endif
+
+    write(mu_serial_fd, &part, 1);
+    fsync(mu_serial_fd);
+  }
+#endif
+}
+
+void mu_serial_palmSerialDataFlush(void)
+{
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  if (mu_serial_fd >= 0) {
+#if defined(MU_SERIAL_DEBUG)
+    // Debug
+    fprintf(stderr, "Serial DROP\n");
+#endif
+
+    tcflush(mu_serial_fd, TCIFLUSH);
+  }
+#endif
+}
+
+void mu_serial_open_and_init(const char* path)
+{
+  mu_serial_path = strdup(path);
+
+#if defined(__LIBRETRO__)
+#elif defined(_WIN32)
+#else
+  mu_serial_fd = -1;
+#endif
+
+#if defined(MU_SERIAL_DEBUG)
+  // Debug
+  fprintf(stderr, "Serial PORT %s\n", mu_serial_path);
+#endif
+
+  // Set functions to use
+  palmSerialSetPortProperties = mu_serial_palmSerialSetPortProperties;
+  palmSerialDataSize = mu_serial_palmSerialDataSize;
+  palmSerialDataReceive = mu_serial_palmSerialDataReceive;
+  palmSerialDataSend = mu_serial_palmSerialDataSend;
+  palmSerialDataFlush = mu_serial_palmSerialDataFlush;
+}