n64: add 64dd disk swapping + safety checks + change manufacture time…

…stamp (#1280)

This adds:
- 64DD Disk Swapping for both 64DD standalone games and N64 Combo games
(only if a disk is loaded).
- Safety checks to prevent corruptions.
- Change manufacture timestamp and line to differenciate different disk
files from each other to avoid confusion

ares/n64/dd/controller.cpp

@@ -187,7 +187,11 @@ auto DD::command(n16 command) -> void {
 auto DD::mechaResponse() -> void {
   if(state.seek) {
     state.seek = 0;
-    motorActive();
+    if (io.status.diskPresent) {
+      motorActive();
+    } else {
+      motorStop();
+    }
   }
   io.status.busyState = 0;
   raise(IRQ::MECHA);

ares/n64/dd/dd.cpp

@@ -31,6 +31,8 @@ auto DD::load(Node::Object parent) -> void {
     iplrom.load(fp);
   }
 
+  rtcLoad();
+
   debugger.load(parent->append<Node::Object>("Nintendo 64DD"));
 }
 
@@ -79,17 +81,45 @@ auto DD::connect() -> void {
   if(auto fp = pak->read("program.disk")) {
     disk.allocate(fp->size());
     disk.load(fp);
+    io.status.diskChanged = 1;
+    io.status.diskPresent = 1;
   }
-
-  rtcLoad();
 }
 
 auto DD::disconnect() -> void {
   if(!port) return;
 
   save();
   pak.reset();
+  disk.reset();
   information = {};
+
+  if(iplrom) {
+    string id;
+    id.append((char)iplrom.read<Byte>(0x3b));
+    id.append((char)iplrom.read<Byte>(0x3c));
+    id.append((char)iplrom.read<Byte>(0x3d));
+    id.append((char)iplrom.read<Byte>(0x3e));
+    if(id.match("NDDJ")) dd.information.cic = "CIC-NUS-8303";
+    if(id.match("NDDE")) dd.information.cic = "CIC-NUS-DDUS";
+    if(id.match("NDXJ")) dd.information.cic = "CIC-NUS-8401";
+  }
+
+  io.status.diskChanged = 0;
+  io.status.diskPresent = 0;
+
+  //Deal with cases when the disk is removed while in use
+  if(io.status.busyState) {
+    //MECHA
+    io.status.mechaError = 1;
+  }
+
+  if(io.bm.start) {
+    //BM
+    io.bm.start = 0;
+    io.bm.error = 1;
+  }
+  motorStop();
 }
 
 auto DD::save() -> void {
@@ -112,6 +142,7 @@ auto DD::power(bool reset) -> void {
   state = {};
 
   io.status.resetState = 1;
+  if(disk) io.status.diskPresent = 1;
   io.id = 3;
   if(dd.information.cic.match("CIC-NUS-8401")) io.id = 4;
 

ares/n64/dd/dd.hpp

@@ -125,6 +125,7 @@ struct DD : Memory::PI<DD> {
       n1 writeProtect;
       n1 mechaError;
       n1 diskChanged;
+      n1 diskPresent;
     } status;
 
     n16 currentTrack;

ares/n64/dd/io.cpp

@@ -20,7 +20,7 @@ auto DD::readHalf(u32 address) -> u16 {
     data.bit(4) = io.status.spindleMotorStopped;
     data.bit(6) = io.status.resetState;
     data.bit(7) = io.status.busyState;
-    data.bit(8) = (bool)disk; //disk present
+    data.bit(8) = io.status.diskPresent;
     data.bit(9) = irq.mecha.line;
     data.bit(10) = irq.bm.line;
     data.bit(11) = io.bm.error;
@@ -57,7 +57,7 @@ auto DD::readHalf(u32 address) -> u16 {
     data.bit(0,7) = io.error.sector;
     data.bit(8) = io.error.selfStop;
     data.bit(9) = io.error.clockUnlock;
-    data.bit(10) = ~(bool)disk; //no disk
+    data.bit(10) = ~io.status.diskPresent; //no disk
     data.bit(11) = io.error.offTrack;
     data.bit(12) = io.error.overrun;
     data.bit(13) = io.error.spindle;

desktop-ui/emulator/nintendo-64.cpp

@@ -1,13 +1,15 @@
 struct Nintendo64 : Emulator {
   Nintendo64();
   auto load() -> bool override;
+  auto load(Menu) -> void override;
   auto save() -> bool override;
   auto pak(ares::Node::Object) -> shared_pointer<vfs::directory> override;
 
   shared_pointer<mia::Pak> gamepad;
   shared_pointer<mia::Pak> disk;
   shared_pointer<mia::Pak> gb;
   u32 regionID = 0;
+  Timer diskInsertTimer;
 };
 
 Nintendo64::Nintendo64() {
@@ -162,6 +164,30 @@ auto Nintendo64::load() -> bool {
   return true;
 }
 
+auto Nintendo64::load(Menu menu) -> void {
+  if(disk) {
+    MenuItem changeDisk{&menu};
+    changeDisk.setIcon(Icon::Device::Optical);
+    changeDisk.setText("Change Disk").onActivate([&] {
+      save();
+      auto drive = root->find<ares::Node::Port>("Nintendo 64DD/Disk Drive");
+      drive->disconnect();
+
+      if(!disk->load(Emulator::load(disk, configuration.game))) {
+        return;
+      }
+
+      //give the emulator core a few seconds to notice an empty drive state before reconnecting
+      diskInsertTimer.onActivate([&] {
+        diskInsertTimer.setEnabled(false);
+        auto drive = root->find<ares::Node::Port>("Nintendo 64DD/Disk Drive");
+        drive->allocate();
+        drive->connect();
+      }).setInterval(3000).setEnabled();
+    });
+  }
+}
+
 auto Nintendo64::save() -> bool {
   root->save();
   system->save(system->location);

desktop-ui/emulator/nintendo-64dd.cpp

@@ -1,11 +1,13 @@
 struct Nintendo64DD : Emulator {
   Nintendo64DD();
   auto load() -> bool override;
+  auto load(Menu) -> void override;
   auto save() -> bool override;
   auto pak(ares::Node::Object) -> shared_pointer<vfs::directory> override;
 
   shared_pointer<mia::Pak> gamepad;
   u32 regionID = 0;
+  Timer diskInsertTimer;
 };
 
 Nintendo64DD::Nintendo64DD() {
@@ -109,6 +111,28 @@ auto Nintendo64DD::load() -> bool {
   return true;
 }
 
+auto Nintendo64DD::load(Menu menu) -> void {
+  MenuItem changeDisk{&menu};
+  changeDisk.setIcon(Icon::Device::Optical);
+  changeDisk.setText("Change Disk").onActivate([&] {
+    save();
+    auto drive = root->find<ares::Node::Port>("Nintendo 64DD/Disk Drive");
+    drive->disconnect();
+
+    if(!game->load(Emulator::load(game, configuration.game))) {
+      return;
+    }
+
+    //give the emulator core a few seconds to notice an empty drive state before reconnecting
+    diskInsertTimer.onActivate([&] {
+      diskInsertTimer.setEnabled(false);
+      auto drive = root->find<ares::Node::Port>("Nintendo 64DD/Disk Drive");
+      drive->allocate();
+      drive->connect();
+    }).setInterval(3000).setEnabled();
+  });
+}
+
 auto Nintendo64DD::save() -> bool {
   root->save();
   system->save(system->location);

mia/medium/nintendo-64dd.cpp

@@ -516,5 +516,42 @@ auto Nintendo64DD::transform(array_view<u8> input, vector<u8> errorTable) -> vec
     }
   }
 
+  //add new timestamp to differenciate every disk file for swapping
+  {
+    //get current time
+    chrono::timeinfo timeinfo = chrono::local::timeinfo();
+
+    u8 rng = random();
+    u8 second = BCD::encode(min(59, timeinfo.second));
+    u8 minute = BCD::encode(timeinfo.minute);
+    u8 hour = BCD::encode(timeinfo.hour);
+    u8 day = BCD::encode(timeinfo.day);
+    u8 month = BCD::encode(1 + timeinfo.month);
+    u8 yearlo = BCD::encode(timeinfo.year % 100);
+    u8 yearhi = BCD::encode(timeinfo.year / 100);
+
+    u32 diskIdBlocks[2] = {14, 15};
+    for(u32 n : range(2)) {
+      u32 offsetCalc = diskIdBlocks[n] * blockSizeTable[0];
+      //change disk id to all sectors
+      for(u32 m : range(85)) {
+        //change manufacture line info (0x08 to 0x0F) (is normally a BCD number but officially "PTN64" was also used there)
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x0B] = rng;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x0C] = 0x41;  //'A'
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x0D] = 0x52;  //'R'
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x0E] = 0x45;  //'E'
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x0F] = 0x53;  //'S'
+        //change disk manufacture time (0x10 to 0x17) to now
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x11] = yearhi;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x12] = yearlo;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x13] = month;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x14] = day;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x15] = hour;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x16] = minute;
+        output[offsetCalc + (m * (blockSizeTable[0] / 85)) + 0x17] = second;
+      }
+    }
+  }
+
   return output;
 }