src/ZXEmuT/tapeaccel.c

   1 /***************************************************************************
   2  *
   3  *  ZXEmuT -- ZX Spectrum Emulator with Tcl scripting
   4  *
   5  *  Copyright (C) 2012-2020 Ketmar Dark <ketmar@ketmar.no-ip.org>
   6  *
   7  *  This program is free software: you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation, version 3 of the License ONLY.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  *
  19  **************************************************************************/
  20 static int tapDetectInCount = 0;
  21 static int tapDetectLastInTS = -666;
  22 static int tapDetectLastInB = 0x00;
  23
  24
  25 void emuTapeAcceleratorEdgeAdvance (int flags) {}
  26 void emuTapeAcceleratorStop (void) {}
  27 void emuTapeAcceleratorStart (void) {}
  28
  29
  30 void emuTapeAcceleratorAdvanceFrame (void) {
  31   if (tapDetectLastInTS > -100666) tapDetectLastInTS -= machineInfo.tsperframe;
  32 }
  33
  34
  35 void emuTapeLoaderDetector (void) {
  36   int tdelta = z80.tstates-tapDetectLastInTS;
  37   uint8_t bdelta = ((int)z80.bc.b-tapDetectLastInB)&0xff;
  38   //
  39   tapDetectLastInTS = z80.tstates;
  40   tapDetectLastInB = z80.bc.b;
  41   //
  42   if (optTapeDetector) {
  43     // detector is on
  44     if (optTapePlaying) {
  45       // tape is playing
  46       if (tdelta > 1000 || (bdelta != 1 && bdelta != 0 && bdelta != 0xff)) {
  47         if (++tapDetectInCount >= 2) {
  48           // seems that this is not a loader anymore
  49           emuStopTape();
  50         }
  51       } else {
  52         tapDetectInCount = 0;
  53       }
  54     } else {
  55       // tape is not playing
  56       if (tdelta <= 500 && (bdelta == 1 || bdelta == 0xff)) {
  57         if (zxCurTape != NULL && !tapNeedRewind) {
  58           if (++tapDetectInCount >= 10) {
  59             // seems that this is LD-EDGE
  60             emuStartTapeAuto();
  61           }
  62         } else {
  63           tapDetectInCount = 0;
  64         }
  65       } else {
  66         tapDetectInCount = 0;
  67       }
  68     }
  69   } else {
  70     // detector is off
  71     tapDetectInCount = 0;
  72   }
  73 }