cdrom: 75/150 sectors per second speed

JaCzekanski · Oct 19, 2021 · e33cbf5 · e33cbf5
1 parent 4ef44fb
commit e33cbf5
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Showing 2 changed files with 5 additions and 8 deletions.
diff --git a/src/device/cdrom/cdrom.cpp b/src/device/cdrom/cdrom.cpp
@@ -12,8 +12,6 @@
 namespace device {
 namespace cdrom {
 
-const int CPU_FREQ = 38'868'800;
-
 CDROM::CDROM(System* sys) : sys(sys) {
     verbose = config.debug.log.cdrom;
     disc = std::make_unique<disc::Empty>();
@@ -151,9 +149,8 @@ void CDROM::step(int cycles) {
         }
     }
 
-    const int CD_SECTOR_SIZE = 2048;
-    const int sectorsPerSecond = (44100 * 2 * 2) / CD_SECTOR_SIZE;
-    const int cyclesPerSector = (CPU_FREQ / sectorsPerSecond) / (mode.speed ? 2 : 1);  // not perfect division
+    const int sectorsPerSecond = mode.speed ? 150 : 75;
+    const int cyclesPerSector = timing::CPU_CLOCK / sectorsPerSecond;
     for (int i = 0; i < readcnt / cyclesPerSector; i++) {
         handleSector();
     }

diff --git a/src/utils/timing.h b/src/utils/timing.h
@@ -13,14 +13,14 @@ const float CYCLES_PER_LINE_PAL = 3406.1f;
 const int LINES_TOTAL_NTSC = 263;
 const int LINES_TOTAL_PAL = 314;
 #else
-const float CYCLES_PER_LINE_NTSC = 3372;
+const float CYCLES_PER_LINE_NTSC = 3372.7f;
 const float CYCLES_PER_LINE_PAL = 3389;
 const int LINES_TOTAL_NTSC = 263;
 const int LINES_TOTAL_PAL = 314;
 #endif
 
-const float NTSC_FRAMERATE = (float)GPU_CLOCK / (CYCLES_PER_LINE_NTSC * LINES_TOTAL_NTSC);
-const float PAL_FRAMERATE = (float)GPU_CLOCK / (CYCLES_PER_LINE_PAL * LINES_TOTAL_PAL);
+const double NTSC_FRAMERATE = (double)GPU_CLOCK / (CYCLES_PER_LINE_NTSC * LINES_TOTAL_NTSC);
+const double PAL_FRAMERATE = (double)GPU_CLOCK / (CYCLES_PER_LINE_PAL * LINES_TOTAL_PAL);
 
 constexpr uint64_t usToCpuCycles(uint64_t us) { return us * CPU_CLOCK / US_IN_SECOND; }
 }  // namespace timing