Shamusworld >> Repos - apple2/blob - src/apple2.cpp

   1 //
   2 // Apple 2 SDL Portable Apple Emulator
   3 //
   4 // by James Hammons
   5 // © 2014 Underground Software
   6 //
   7 // Loosely based on AppleWin by Tom Charlesworth which was based on AppleWin by
   8 // Oliver Schmidt which was based on AppleWin by Michael O'Brien. :-) Parts are
   9 // also derived from ApplePC. Too bad it was closed source--it could have been
  10 // *the* premier Apple II emulator out there.
  11 //
  12 // JLH = James Hammons <jlhamm@acm.org>
  13 //
  14 // WHO  WHEN        WHAT
  15 // ---  ----------  -----------------------------------------------------------
  16 // JLH  11/12/2005  Initial port to SDL
  17 // JLH  11/18/2005  Wired up graphic soft switches
  18 // JLH  12/02/2005  Setup timer subsystem for more accurate time keeping
  19 // JLH  12/12/2005  Added preliminary state saving support
  20 // JLH  09/24/2013  Added //e support
  21 //
  22
  23 // STILL TO DO:
  24 //
  25 // - Port to SDL [DONE]
  26 // - GUI goodies
  27 // - Weed out unneeded functions [DONE]
  28 // - Disk I/O [DONE]
  29 // - 128K IIe related stuff [DONE]
  30 // - State loading/saving
  31 //
  32
  33 #include "apple2.h"
  34
  35 #include <SDL2/SDL.h>
  36 #include <fstream>
  37 #include <string>
  38 #include <iomanip>
  39 #include <iostream>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <time.h>
  43 #include "log.h"
  44 #include "video.h"
  45 #include "sound.h"
  46 #include "settings.h"
  47 #include "v65c02.h"
  48 #include "applevideo.h"
  49 #include "timing.h"
  50 #include "floppy.h"
  51 #include "firmware.h"
  52 #include "mmu.h"
  53
  54 #include "gui/gui.h"
  55
  56 // Debug and misc. defines
  57
  58 #define THREADED_65C02
  59 #define CPU_THREAD_OVERFLOW_COMPENSATION
  60 #define DEBUG_LC
  61 //#define CPU_CLOCK_CHECKING
  62 //#define THREAD_DEBUGGING
  63 #define SOFT_SWITCH_DEBUGGING
  64
  65 // Global variables
  66
  67 uint8_t ram[0x10000], rom[0x10000];                     // RAM & ROM spaces
  68 uint8_t ram2[0x10000];                                          // Auxillary RAM
  69 V65C02REGS mainCPU;                                                     // v65C02 execution context
  70 uint8_t appleType = APPLE_TYPE_IIE;
  71 FloppyDrive floppyDrive;
  72 bool powerStateChangeRequested = false;
  73
  74 // Local variables (actually, they're global since they're not static)
  75
  76 uint8_t lastKeyPressed = 0;
  77 bool keyDown = false;
  78 bool openAppleDown = false;
  79 bool closedAppleDown = false;
  80 bool store80Mode = false;
  81 bool vbl = false;
  82 bool slotCXROM = false;
  83 bool slotC3ROM = false;
  84 bool ramrd = false;
  85 bool ramwrt = false;
  86 bool altzp = false;
  87 bool ioudis = true;
  88 bool dhires = false;
  89 // Language card state (ROM read, no write)
  90 uint8_t lcState = 0x02;
  91
  92 static bool running = true;                                     // Machine running state flag...
  93 static uint32_t startTicks;
  94 static bool pauseMode = false;
  95 static bool fullscreenDebounce = false;
  96 static bool capsLock = false;
  97 static bool capsLockDebounce = false;
  98
  99 // Local functions
 100
 101 static void SaveApple2State(const char * filename);
 102 static bool LoadApple2State(const char * filename);
 103 static void ResetApple2State(void);
 104
 105 // Local timer callback functions
 106
 107 static void FrameCallback(void);
 108 static void BlinkTimer(void);
 109
 110 #ifdef THREADED_65C02
 111 // Test of threaded execution of 6502
 112 static SDL_Thread * cpuThread = NULL;
 113 //static SDL_mutex * cpuMutex = NULL;
 114 static SDL_cond * cpuCond = NULL;
 115 static SDL_sem * mainSem = NULL;
 116 static bool cpuFinished = false;
 117 //static bool cpuSleep = false;
 118
 119 // NB: Apple //e Manual sez 6502 is running @ 1,022,727 Hz
 120
 121 // Let's try a thread...
 122 //
 123 // Here's how it works: Execute 1 frame's worth, then sleep. Other stuff wakes
 124 // it up
 125 //
 126 int CPUThreadFunc(void * data)
 127 {
 128         // Mutex must be locked for conditional to work...
 129         // Also, must be created in the thread that uses it...
 130         SDL_mutex * cpuMutex = SDL_CreateMutex();
 131
 132 // decrement mainSem...
 133 //SDL_SemWait(mainSem);
 134 #ifdef CPU_THREAD_OVERFLOW_COMPENSATION
 135         float overflow = 0.0;
 136 #endif
 137
 138         do
 139         {
 140 // This is never set to true anywhere...
 141 //              if (cpuSleep)
 142 //                      SDL_CondWait(cpuCond, cpuMutex);
 143
 144 // decrement mainSem...
 145 #ifdef THREAD_DEBUGGING
 146 WriteLog("CPU: SDL_SemWait(mainSem);\n");
 147 #endif
 148                 SDL_SemWait(mainSem);
 149
 150 // There are exactly 800 slices of 21.333 cycles per frame, so it works out
 151 // evenly.
 152 #ifdef THREAD_DEBUGGING
 153 WriteLog("CPU: Execute65C02(&mainCPU, cycles);\n");
 154 #endif
 155                 for(int i=0; i<800; i++)
 156                 {
 157                         uint32_t cycles = 21;
 158                         overflow += 0.333333334;
 159
 160                         if (overflow > 1.0)
 161                         {
 162                                 cycles++;
 163                                 overflow -= 1.0;
 164                         }
 165
 166                         Execute65C02(&mainCPU, cycles);
 167                         WriteSampleToBuffer();
 168
 169                         // Dunno if this is correct (seems to be close enough)...
 170                         vbl = (i < 670 ? true : false);
 171                 }
 172
 173 #ifdef THREAD_DEBUGGING
 174 WriteLog("CPU: SDL_mutexP(cpuMutex);\n");
 175 #endif
 176                 SDL_mutexP(cpuMutex);
 177 // increment mainSem...
 178 #ifdef THREAD_DEBUGGING
 179 WriteLog("CPU: SDL_SemPost(mainSem);\n");
 180 #endif
 181                 SDL_SemPost(mainSem);
 182 #ifdef THREAD_DEBUGGING
 183 WriteLog("CPU: SDL_CondWait(cpuCond, cpuMutex);\n");
 184 #endif
 185                 SDL_CondWait(cpuCond, cpuMutex);
 186
 187 #ifdef THREAD_DEBUGGING
 188 WriteLog("CPU: SDL_mutexV(cpuMutex);\n");
 189 #endif
 190                 SDL_mutexV(cpuMutex);
 191         }
 192         while (!cpuFinished);
 193
 194         SDL_DestroyMutex(cpuMutex);
 195
 196         return 0;
 197 }
 198 #endif
 199
 200
 201 //
 202 // Request a change in the power state of the emulated Apple
 203 //
 204 void SetPowerState(void)
 205 {
 206         powerStateChangeRequested = true;
 207 }
 208
 209
 210 //
 211 // Load a file into RAM/ROM image space
 212 //
 213 bool LoadImg(char * filename, uint8_t * ram, int size)
 214 {
 215         FILE * fp = fopen(filename, "rb");
 216
 217         if (fp == NULL)
 218                 return false;
 219
 220         fread(ram, 1, size, fp);
 221         fclose(fp);
 222
 223         return true;
 224 }
 225
 226
 227 const uint8_t stateHeader[19] = "APPLE2SAVESTATE1.0";
 228 static void SaveApple2State(const char * filename)
 229 {
 230         WriteLog("Main: Saving Apple2 state...\n");
 231         FILE * file = fopen(filename, "wb");
 232
 233         if (!file)
 234         {
 235                 WriteLog("Could not open file \"%s\" for writing!\n", filename);
 236                 return;
 237         }
 238
 239         // Write out header
 240         fwrite(stateHeader, 1, 18, file);
 241
 242         // Write out CPU state
 243         fwrite(&mainCPU, 1, sizeof(mainCPU), file);
 244
 245         // Write out main memory
 246         fwrite(ram, 1, 0x10000, file);
 247         fwrite(ram2, 1, 0x10000, file);
 248
 249         // Write out state variables
 250         fputc((uint8_t)keyDown, file);
 251         fputc((uint8_t)openAppleDown, file);
 252         fputc((uint8_t)closedAppleDown, file);
 253         fputc((uint8_t)store80Mode, file);
 254         fputc((uint8_t)vbl, file);
 255         fputc((uint8_t)slotCXROM, file);
 256         fputc((uint8_t)slotC3ROM, file);
 257         fputc((uint8_t)ramrd, file);
 258         fputc((uint8_t)ramwrt, file);
 259         fputc((uint8_t)altzp, file);
 260         fputc((uint8_t)ioudis, file);
 261         fputc((uint8_t)dhires, file);
 262         fputc((uint8_t)flash, file);
 263         fputc((uint8_t)textMode, file);
 264         fputc((uint8_t)mixedMode, file);
 265         fputc((uint8_t)displayPage2, file);
 266         fputc((uint8_t)hiRes, file);
 267         fputc((uint8_t)alternateCharset, file);
 268         fputc((uint8_t)col80Mode, file);
 269         fputc(lcState, file);
 270
 271         // Write out floppy state
 272         floppyDrive.SaveState(file);
 273         fclose(file);
 274 }
 275
 276
 277 static bool LoadApple2State(const char * filename)
 278 {
 279         WriteLog("Main: Loading Apple2 state...\n");
 280         FILE * file = fopen(filename, "rb");
 281
 282         if (!file)
 283         {
 284                 WriteLog("Could not open file \"%s\" for reading!\n", filename);
 285                 return false;
 286         }
 287
 288         uint8_t buffer[18];
 289         fread(buffer, 1, 18, file);
 290
 291         // Sanity check...
 292         if (memcmp(buffer, stateHeader, 18) != 0)
 293         {
 294                 fclose(file);
 295                 WriteLog("File \"%s\" is not a valid Apple2 save state file!\n", filename);
 296                 return false;
 297         }
 298
 299         // Read CPU state
 300         fread(&mainCPU, 1, sizeof(mainCPU), file);
 301
 302         // Read main memory
 303         fread(ram, 1, 0x10000, file);
 304         fread(ram2, 1, 0x10000, file);
 305
 306         // Read in state variables
 307         keyDown = (bool)fgetc(file);
 308         openAppleDown = (bool)fgetc(file);
 309         closedAppleDown = (bool)fgetc(file);
 310         store80Mode = (bool)fgetc(file);
 311         vbl = (bool)fgetc(file);
 312         slotCXROM = (bool)fgetc(file);
 313         slotC3ROM = (bool)fgetc(file);
 314         ramrd = (bool)fgetc(file);
 315         ramwrt = (bool)fgetc(file);
 316         altzp = (bool)fgetc(file);
 317         ioudis = (bool)fgetc(file);
 318         dhires = (bool)fgetc(file);
 319         flash = (bool)fgetc(file);
 320         textMode = (bool)fgetc(file);
 321         mixedMode = (bool)fgetc(file);
 322         displayPage2 = (bool)fgetc(file);
 323         hiRes = (bool)fgetc(file);
 324         alternateCharset = (bool)fgetc(file);
 325         col80Mode = (bool)fgetc(file);
 326         lcState = fgetc(file);
 327
 328         // Read in floppy state
 329         floppyDrive.LoadState(file);
 330
 331         fclose(file);
 332
 333         // Make sure things are in a sane state before execution :-P
 334         mainCPU.RdMem = AppleReadMem;
 335         mainCPU.WrMem = AppleWriteMem;
 336         ResetMMUPointers();
 337
 338         return true;
 339 }
 340
 341
 342 static void ResetApple2State(void)
 343 {
 344         keyDown = false;
 345         openAppleDown = false;
 346         closedAppleDown = false;
 347         store80Mode = false;
 348         vbl = false;
 349         slotCXROM = false;
 350         slotC3ROM = false;
 351         ramrd = false;
 352         ramwrt = false;
 353         altzp = false;
 354         ioudis = true;
 355         dhires = false;
 356         lcState = 0x02;
 357         ResetMMUPointers();
 358
 359         // Without this, you can wedge the system :-/
 360         memset(ram, 0, 0x10000);
 361         mainCPU.cpuFlags |= V65C02_ASSERT_LINE_RESET;
 362 }
 363
 364
 365 #ifdef CPU_CLOCK_CHECKING
 366 uint8_t counter = 0;
 367 uint32_t totalCPU = 0;
 368 uint64_t lastClock = 0;
 369 #endif
 370 //
 371 // Main loop
 372 //
 373 int main(int /*argc*/, char * /*argv*/[])
 374 {
 375         InitLog("./apple2.log");
 376         LoadSettings();
 377         srand(time(NULL));                                                                      // Initialize RNG
 378
 379         // Zero out memory
 380         memset(ram, 0, 0x10000);
 381         memset(rom, 0, 0x10000);
 382         memset(ram2, 0, 0x10000);
 383
 384         // Set up MMU
 385         SetupAddressMap();
 386         ResetMMUPointers();
 387
 388         // Set up V65C02 execution context
 389         memset(&mainCPU, 0, sizeof(V65C02REGS));
 390         mainCPU.RdMem = AppleReadMem;
 391         mainCPU.WrMem = AppleWriteMem;
 392         mainCPU.cpuFlags |= V65C02_ASSERT_LINE_RESET;
 393
 394         if (!LoadImg(settings.BIOSPath, rom + 0xC000, 0x4000))
 395         {
 396                 WriteLog("Could not open file '%s'!\n", settings.BIOSPath);
 397                 return -1;
 398         }
 399
 400         WriteLog("About to initialize video...\n");
 401
 402         if (!InitVideo())
 403         {
 404                 std::cout << "Aborting!" << std::endl;
 405                 return -1;
 406         }
 407
 408         GUI::Init(sdlRenderer);
 409
 410         // Have to do this *after* video init but *before* sound init...!
 411 //Shouldn't be necessary since we're not doing emulation in the ISR...
 412         if (settings.autoStateSaving)
 413         {
 414                 // Load last state from file...
 415                 if (!LoadApple2State(settings.autoStatePath))
 416                         WriteLog("Unable to use Apple2 state file \"%s\"!\n", settings.autoStatePath);
 417         }
 418
 419         WriteLog("About to initialize audio...\n");
 420         SoundInit();
 421         SetupBlurTable();                                                       // Set up the color TV emulation blur table
 422         running = true;                                                         // Set running status...
 423         InitializeEventList();                                          // Clear the event list before we use it...
 424         SetCallbackTime(FrameCallback, 16666.66666667); // Set frame to fire at 1/60 s interval
 425         SetCallbackTime(BlinkTimer, 250000);            // Set up blinking at 1/4 s intervals
 426         startTicks = SDL_GetTicks();
 427
 428 #ifdef THREADED_65C02
 429         cpuCond = SDL_CreateCond();
 430         mainSem = SDL_CreateSemaphore(1);
 431         cpuThread = SDL_CreateThread(CPUThreadFunc, NULL, NULL);
 432 //Hmm... CPU does POST (+1), wait, then WAIT (-1)
 433 //      SDL_sem * mainMutex = SDL_CreateMutex();
 434 #endif
 435
 436         WriteLog("Entering main loop...\n");
 437
 438         while (running)
 439         {
 440                 double timeToNextEvent = GetTimeToNextEvent();
 441 #ifndef THREADED_65C02
 442                 Execute65C02(&mainCPU, USEC_TO_M6502_CYCLES(timeToNextEvent));
 443
 444         #ifdef CPU_CLOCK_CHECKING
 445 totalCPU += USEC_TO_M6502_CYCLES(timeToNextEvent);
 446         #endif
 447 #endif
 448                 HandleNextEvent();
 449         }
 450
 451 #ifdef THREADED_65C02
 452 WriteLog("Main: cpuFinished = true;\n");
 453         cpuFinished = true;
 454
 455 WriteLog("Main: SDL_SemWait(mainSem);\n");
 456         // Only do this if NOT in power off/emulation paused mode!
 457         if (!pauseMode)
 458                 // Should lock until CPU thread is waiting...
 459                 SDL_SemWait(mainSem);
 460 #endif
 461
 462 WriteLog("Main: SDL_CondSignal(cpuCond);\n");
 463         SDL_CondSignal(cpuCond);//thread is probably asleep, so wake it up
 464 WriteLog("Main: SDL_WaitThread(cpuThread, NULL);\n");
 465         SDL_WaitThread(cpuThread, NULL);
 466 WriteLog("Main: SDL_DestroyCond(cpuCond);\n");
 467         SDL_DestroyCond(cpuCond);
 468         SDL_DestroySemaphore(mainSem);
 469
 470         // Autosave state here, if requested...
 471         if (settings.autoStateSaving)
 472                 SaveApple2State(settings.autoStatePath);
 473
 474         floppyDrive.SaveImage(0);
 475         floppyDrive.SaveImage(1);
 476
 477         SoundDone();
 478         VideoDone();
 479         SaveSettings();
 480         LogDone();
 481
 482         return 0;
 483 }
 484
 485
 486 /*
 487 Apple II keycodes
 488 -----------------
 489
 490 Key     Aln CTL SHF BTH
 491 -----------------------
 492 space   $A0     $A0     $A0 $A0         No xlation
 493 RETURN  $8D     $8D     $8D     $8D             No xlation
 494 0               $B0     $B0     $B0     $B0             Need to screen shift+0 (?)
 495 1!              $B1 $B1 $A1 $A1         No xlation
 496 2"              $B2     $B2     $A2     $A2             No xlation
 497 3#              $B3     $B3     $A3     $A3             No xlation
 498 4$              $B4     $B4     $A4     $A4             No xlation
 499 5%              $B5     $B5     $A5     $A5             No xlation
 500 6&              $B6     $B6     $A6     $A6             No xlation
 501 7'              $B7     $B7     $A7     $A7             No xlation
 502 8(              $B8     $B8     $A8     $A8             No xlation
 503 9)              $B9     $B9     $A9     $A9             No xlation
 504 :*              $BA     $BA     $AA     $AA             No xlation
 505 ;+              $BB     $BB     $AB     $AB             No xlation
 506 ,<              $AC     $AC     $BC     $BC             No xlation
 507 -=              $AD     $AD     $BD     $BD             No xlation
 508 .>              $AE     $AE     $BE     $BE             No xlation
 509 /?              $AF     $AF     $BF     $BF             No xlation
 510 A               $C1     $81     $C1     $81
 511 B               $C2     $82     $C2     $82
 512 C               $C3     $83     $C3     $83
 513 D               $C4     $84     $C4     $84
 514 E               $C5     $85     $C5     $85
 515 F               $C6     $86     $C6     $86
 516 G               $C7     $87     $C7     $87
 517 H               $C8     $88     $C8     $88
 518 I               $C9     $89     $C9     $89
 519 J               $CA     $8A     $CA     $8A
 520 K               $CB     $8B     $CB     $8B
 521 L               $CC     $8C     $CC     $8C
 522 M               $CD     $8D     $DD     $9D             -> ODD
 523 N^              $CE     $8E     $DE     $9E             -> ODD
 524 O               $CF     $8F     $CF     $8F
 525 P@              $D0     $90     $C0     $80             Need to xlate CTL+SHFT+P & SHFT+P (?)
 526 Q               $D1     $91     $D1     $91
 527 R               $D2     $92     $D2     $92
 528 S               $D3     $93     $D3     $93
 529 T               $D4     $94     $D4     $94
 530 U               $D5     $95     $D5     $95
 531 V               $D6     $96     $D6     $96
 532 W               $D7     $97     $D7     $97
 533 X               $D8     $98     $D8     $98
 534 Y               $D9     $99     $D9     $99
 535 Z               $DA     $9A     $DA     $9A
 536 <-              $88     $88     $88     $88
 537 ->              $95     $95     $95     $95
 538 ESC             $9B     $9B     $9B     $9B             No xlation
 539 */
 540
 541 static uint32_t frameCount = 0;
 542 static void FrameCallback(void)
 543 {
 544         SDL_Event event;
 545
 546         while (SDL_PollEvent(&event))
 547         {
 548                 switch (event.type)
 549                 {
 550 // Problem with using SDL_TEXTINPUT is that it causes key delay. :-/
 551 #if 0
 552                 case SDL_TEXTINPUT:
 553 //Need to do some key translation here, and screen out non-apple keys as well...
 554 //(really, could do it all in SDL_KEYDOWN, would just have to get symbols &
 555 // everything else done separately. this is slightly easier. :-P)
 556 //                      if (event.key.keysym.sym == SDLK_TAB)   // Prelim key screening...
 557                         if (event.edit.text[0] == '\t') // Prelim key screening...
 558                                 break;
 559
 560                         lastKeyPressed = event.edit.text[0];
 561                         keyDown = true;
 562
 563                         //kludge: should have a caps lock thingy here...
 564                         //or all uppercase for ][+...
 565 //                      if (lastKeyPressed >= 'a' && lastKeyPressed <='z')
 566 //                              lastKeyPressed &= 0xDF;         // Convert to upper case...
 567
 568                         break;
 569 #endif
 570                 case SDL_KEYDOWN:
 571                         // Use CTRL+SHIFT+Q to exit, as well as the usual window decoration
 572                         // method
 573                         if ((event.key.keysym.mod & KMOD_CTRL)
 574                                 && (event.key.keysym.mod & KMOD_SHIFT)
 575                                 && (event.key.keysym.sym == SDLK_q))
 576                         {
 577                                 running = false;
 578                                 // We return here, because we don't want to pick up any
 579                                 // spurious keypresses with our exit sequence.
 580                                 return;
 581                         }
 582
 583                         // CTRL+RESET key emulation (mapped to CTRL+`)
 584 // This doesn't work...
 585 //                      if (event.key.keysym.sym == SDLK_BREAK && (event.key.keysym.mod & KMOD_CTRL))
 586 //                      if (event.key.keysym.sym == SDLK_PAUSE && (event.key.keysym.mod & KMOD_CTRL))
 587                         if ((event.key.keysym.mod & KMOD_CTRL)
 588                                 && (event.key.keysym.sym == SDLK_BACKQUOTE))
 589                         {
 590 //NOTE that this shouldn't take place until the key is lifted... !!! FIX !!!
 591 //ALSO it seems to leave the machine in an inconsistent state vis-a-vis the language card...
 592                                 mainCPU.cpuFlags |= V65C02_ASSERT_LINE_RESET;
 593                                 break;
 594                         }
 595
 596                         if (event.key.keysym.sym == SDLK_RIGHT)
 597                                 lastKeyPressed = 0x15, keyDown = true;
 598                         else if (event.key.keysym.sym == SDLK_LEFT)
 599                                 lastKeyPressed = 0x08, keyDown = true;
 600                         else if (event.key.keysym.sym == SDLK_UP)
 601                                 lastKeyPressed = 0x0B, keyDown = true;
 602                         else if (event.key.keysym.sym == SDLK_DOWN)
 603                                 lastKeyPressed = 0x0A, keyDown = true;
 604                         else if (event.key.keysym.sym == SDLK_RETURN)
 605                                 lastKeyPressed = 0x0D, keyDown = true;
 606                         else if (event.key.keysym.sym == SDLK_ESCAPE)
 607                                 lastKeyPressed = 0x1B, keyDown = true;
 608                         else if (event.key.keysym.sym == SDLK_BACKSPACE)
 609                                 lastKeyPressed = 0x7F, keyDown = true;
 610
 611                         // Fix CTRL+key combo...
 612                         if (event.key.keysym.mod & KMOD_CTRL)
 613                         {
 614                                 if (event.key.keysym.sym >= SDLK_a && event.key.keysym.sym <= SDLK_z)
 615                                 {
 616                                         lastKeyPressed = (event.key.keysym.sym - SDLK_a) + 1;
 617                                         keyDown = true;
 618 //printf("Key combo pressed: CTRL+%c\n", lastKeyPressed + 0x40);
 619                                         break;
 620                                 }
 621                         }
 622
 623 #if 1
 624                         // Fix SHIFT+key combo...
 625                         if (event.key.keysym.mod & KMOD_SHIFT)
 626                         {
 627                                 if (event.key.keysym.sym >= SDLK_a && event.key.keysym.sym <= SDLK_z)
 628                                 {
 629                                         lastKeyPressed = (event.key.keysym.sym - SDLK_a) + 0x41;
 630                                         keyDown = true;
 631 //printf("Key combo pressed: CTRL+%c\n", lastKeyPressed + 0x40);
 632                                         break;
 633                                 }
 634                                 else if (event.key.keysym.sym == SDLK_1)
 635                                 {
 636                                         lastKeyPressed = '!';
 637                                         keyDown = true;
 638                                         break;
 639                                 }
 640                                 else if (event.key.keysym.sym == SDLK_2)
 641                                 {
 642                                         lastKeyPressed = '@';
 643                                         keyDown = true;
 644                                         break;
 645                                 }
 646                                 else if (event.key.keysym.sym == SDLK_3)
 647                                 {
 648                                         lastKeyPressed = '#';
 649                                         keyDown = true;
 650                                         break;
 651                                 }
 652                                 else if (event.key.keysym.sym == SDLK_4)
 653                                 {
 654                                         lastKeyPressed = '$';
 655                                         keyDown = true;
 656                                         break;
 657                                 }
 658                                 else if (event.key.keysym.sym == SDLK_5)
 659                                 {
 660                                         lastKeyPressed = '%';
 661                                         keyDown = true;
 662                                         break;
 663                                 }
 664                                 else if (event.key.keysym.sym == SDLK_6)
 665                                 {
 666                                         lastKeyPressed = '^';
 667                                         keyDown = true;
 668                                         break;
 669                                 }
 670                                 else if (event.key.keysym.sym == SDLK_7)
 671                                 {
 672                                         lastKeyPressed = '&';
 673                                         keyDown = true;
 674                                         break;
 675                                 }
 676                                 else if (event.key.keysym.sym == SDLK_8)
 677                                 {
 678                                         lastKeyPressed = '*';
 679                                         keyDown = true;
 680                                         break;
 681                                 }
 682                                 else if (event.key.keysym.sym == SDLK_9)
 683                                 {
 684                                         lastKeyPressed = '(';
 685                                         keyDown = true;
 686                                         break;
 687                                 }
 688                                 else if (event.key.keysym.sym == SDLK_0)
 689                                 {
 690                                         lastKeyPressed = ')';
 691                                         keyDown = true;
 692                                         break;
 693                                 }
 694                                 else if (event.key.keysym.sym == SDLK_MINUS)
 695                                 {
 696                                         lastKeyPressed = '_';
 697                                         keyDown = true;
 698                                         break;
 699                                 }
 700                                 else if (event.key.keysym.sym == SDLK_EQUALS)
 701                                 {
 702                                         lastKeyPressed = '+';
 703                                         keyDown = true;
 704                                         break;
 705                                 }
 706                                 else if (event.key.keysym.sym == SDLK_LEFTBRACKET)
 707                                 {
 708                                         lastKeyPressed = '{';
 709                                         keyDown = true;
 710                                         break;
 711                                 }
 712                                 else if (event.key.keysym.sym == SDLK_RIGHTBRACKET)
 713                                 {
 714                                         lastKeyPressed = '}';
 715                                         keyDown = true;
 716                                         break;
 717                                 }
 718                                 else if (event.key.keysym.sym == SDLK_BACKSLASH)
 719                                 {
 720                                         lastKeyPressed = '|';
 721                                         keyDown = true;
 722                                         break;
 723                                 }
 724                                 else if (event.key.keysym.sym == SDLK_SEMICOLON)
 725                                 {
 726                                         lastKeyPressed = ':';
 727                                         keyDown = true;
 728                                         break;
 729                                 }
 730                                 else if (event.key.keysym.sym == SDLK_QUOTE)
 731                                 {
 732                                         lastKeyPressed = '"';
 733                                         keyDown = true;
 734                                         break;
 735                                 }
 736                                 else if (event.key.keysym.sym == SDLK_COMMA)
 737                                 {
 738                                         lastKeyPressed = '<';
 739                                         keyDown = true;
 740                                         break;
 741                                 }
 742                                 else if (event.key.keysym.sym == SDLK_PERIOD)
 743                                 {
 744                                         lastKeyPressed = '>';
 745                                         keyDown = true;
 746                                         break;
 747                                 }
 748                                 else if (event.key.keysym.sym == SDLK_SLASH)
 749                                 {
 750                                         lastKeyPressed = '?';
 751                                         keyDown = true;
 752                                         break;
 753                                 }
 754                                 else if (event.key.keysym.sym == SDLK_BACKQUOTE)
 755                                 {
 756                                         lastKeyPressed = '~';
 757                                         keyDown = true;
 758                                         break;
 759                                 }
 760                         }
 761 #endif
 762
 763                         // General keys...
 764                         if (event.key.keysym.sym >= SDLK_SPACE && event.key.keysym.sym <= SDLK_z)
 765                         {
 766                                 lastKeyPressed = event.key.keysym.sym;
 767                                 keyDown = true;
 768
 769                                 // Check for Caps Lock key...
 770                                 if (event.key.keysym.sym >= SDLK_a && event.key.keysym.sym <= SDLK_z && capsLock)
 771                                         lastKeyPressed -= 0x20;
 772
 773                                 break;
 774                         }
 775
 776                         if (event.key.keysym.sym == SDLK_PAUSE)
 777                         {
 778                                 pauseMode = !pauseMode;
 779
 780                                 if (pauseMode)
 781                                 {
 782                                         SoundPause();
 783                                         SpawnMessage("*** PAUSED ***");
 784                                 }
 785                                 else
 786                                 {
 787                                         SoundResume();
 788                                         SpawnMessage("*** RESUME ***");
 789                                 }
 790                         }
 791
 792                         // Paddle buttons 0 & 1
 793                         if (event.key.keysym.sym == SDLK_LALT)
 794                                 openAppleDown = true;
 795                         if (event.key.keysym.sym == SDLK_RALT)
 796                                 closedAppleDown = true;
 797
 798                         if (event.key.keysym.sym == SDLK_F11)
 799                                 dumpDis = !dumpDis;                             // Toggle the disassembly process
 800
 801 /*else if (event.key.keysym.sym == SDLK_F9)
 802 {
 803         floppyDrive.CreateBlankImage(0);
 804 //      SpawnMessage("Image cleared...");
 805 }//*/
 806 /*else if (event.key.keysym.sym == SDLK_F10)
 807 {
 808         floppyDrive.SwapImages();
 809 //      SpawnMessage("Image swapped...");
 810 }//*/
 811
 812                         if (event.key.keysym.sym == SDLK_F2)
 813                                 TogglePalette();
 814                         else if (event.key.keysym.sym == SDLK_F3)
 815                                 CycleScreenTypes();
 816                         else if (event.key.keysym.sym == SDLK_F5)
 817                         {
 818                                 VolumeDown();
 819                                 char volStr[19] = "[****************]";
 820
 821                                 for(int i=GetVolume(); i<16; i++)
 822                                         volStr[1 + i] = '-';
 823
 824                                 SpawnMessage("Volume: %s", volStr);
 825                         }
 826                         else if (event.key.keysym.sym == SDLK_F6)
 827                         {
 828                                 VolumeUp();
 829                                 char volStr[19] = "[****************]";
 830
 831                                 for(int i=GetVolume(); i<16; i++)
 832                                         volStr[1 + i] = '-';
 833
 834                                 SpawnMessage("Volume: %s", volStr);
 835                         }
 836                         else if (event.key.keysym.sym == SDLK_F12)
 837                         {
 838                                 if (!fullscreenDebounce)
 839                                 {
 840                                         ToggleFullScreen();
 841                                         fullscreenDebounce = true;
 842                                 }
 843                         }
 844
 845                         if (event.key.keysym.sym == SDLK_CAPSLOCK)
 846                         {
 847                                 if (!capsLockDebounce)
 848                                 {
 849                                         capsLock = !capsLock;
 850                                         capsLockDebounce = true;
 851                                 }
 852                         }
 853
 854                         break;
 855                 case SDL_KEYUP:
 856                         if (event.key.keysym.sym == SDLK_F12)
 857                                 fullscreenDebounce = false;
 858                         if (event.key.keysym.sym == SDLK_CAPSLOCK)
 859                                 capsLockDebounce = false;
 860
 861                         // Paddle buttons 0 & 1
 862                         if (event.key.keysym.sym == SDLK_LALT)
 863                                 openAppleDown = false;
 864                         if (event.key.keysym.sym == SDLK_RALT)
 865                                 closedAppleDown = false;
 866
 867                         break;
 868                 case SDL_MOUSEBUTTONDOWN:
 869                         GUI::MouseDown(event.motion.x, event.motion.y, event.motion.state);
 870                         break;
 871                 case SDL_MOUSEBUTTONUP:
 872                         GUI::MouseUp(event.motion.x, event.motion.y, event.motion.state);
 873                         break;
 874                 case SDL_MOUSEMOTION:
 875                         GUI::MouseMove(event.motion.x, event.motion.y, event.motion.state);
 876                         break;
 877                 case SDL_WINDOWEVENT:
 878                         if (event.window.event == SDL_WINDOWEVENT_LEAVE)
 879                                 GUI::MouseMove(0, 0, 0);
 880
 881                         break;
 882                 case SDL_QUIT:
 883                         running = false;
 884                 }
 885         }
 886
 887         // Handle power request from the GUI
 888         if (powerStateChangeRequested)
 889         {
 890                 if (GUI::powerOnState)
 891                 {
 892                         pauseMode = false;
 893                         // Unlock the CPU thread...
 894                         SDL_SemPost(mainSem);
 895                 }
 896                 else
 897                 {
 898                         pauseMode = true;
 899                         // Should lock until CPU thread is waiting...
 900                         SDL_SemWait(mainSem);
 901                         ResetApple2State();
 902                 }
 903
 904                 powerStateChangeRequested = false;
 905         }
 906
 907         RenderVideoFrame();                             // Render Apple screen to buffer
 908         RenderScreenBuffer();                   // Render buffer to host screen
 909         GUI::Render(sdlRenderer);
 910         SDL_RenderPresent(sdlRenderer);
 911         SetCallbackTime(FrameCallback, 16666.66666667);
 912
 913 #ifdef CPU_CLOCK_CHECKING
 914 //We know it's stopped, so we can get away with this...
 915 counter++;
 916 if (counter == 60)
 917 {
 918         uint64_t clock = GetCurrentV65C02Clock();
 919 //totalCPU += (uint32_t)(clock - lastClock);
 920
 921         printf("Executed %u cycles...\n", (uint32_t)(clock - lastClock));
 922         lastClock = clock;
 923 //      totalCPU = 0;
 924         counter = 0;
 925 }
 926 #endif
 927
 928 // This is the problem: If you set the interval to 16, it runs faster than
 929 // 1/60s per frame. If you set it to 17, it runs slower. What we need is to
 930 // have it do 16 for one frame, then 17 for two others. Then it should average
 931 // out to 1/60s per frame every 3 frames.
 932         frameCount = (frameCount + 1) % 3;
 933         uint32_t waitFrameTime = 17 - (frameCount == 0 ? 1 : 0);
 934
 935         // Wait for next frame...
 936         while (SDL_GetTicks() - startTicks < waitFrameTime)
 937                 SDL_Delay(1);
 938
 939         startTicks = SDL_GetTicks();
 940 #if 0
 941         uint64_t cpuCycles = GetCurrentV65C02Clock();
 942         uint32_t cyclesBurned = (uint32_t)(cpuCycles - lastCPUCycles);
 943         WriteLog("FrameCallback: used %i cycles\n", cyclesBurned);
 944         lastCPUCycles = cpuCycles
 945 #endif
 946
 947 //let's wait, then signal...
 948 //works longer, but then still falls behind... [FIXED, see above]
 949 #ifdef THREADED_65C02
 950         if (!pauseMode)
 951                 SDL_CondSignal(cpuCond);//OK, let the CPU go another frame...
 952 #endif
 953 }
 954
 955
 956 static void BlinkTimer(void)
 957 {
 958         // Set up blinking at 1/4 sec intervals
 959         flash = !flash;
 960         SetCallbackTime(BlinkTimer, 250000);
 961 }
 962
 963
 964 /*
 965 Next problem is this: How to have events occur and synchronize with the rest
 966 of the threads?
 967
 968   o Have the CPU thread manage the timer mechanism? (need to have a method of carrying
 969     remainder CPU cycles over...)
 970
 971 One way would be to use a fractional accumulator, then subtract 1 every
 972 time it overflows. Like so:
 973
 974 double overflow = 0;
 975 uint32_t time = 20;
 976 while (!done)
 977 {
 978         Execute6808(&soundCPU, time);
 979         overflow += 0.289115646;
 980         if (overflow > 1.0)
 981         {
 982                 overflow -= 1.0;
 983                 time = 21;
 984         }
 985         else
 986                 time = 20;
 987 }
 988 */
 989