sms: do psg like md does

[picodrive.git] / pico / sms.c

diff --git a/pico/sms.c b/pico/sms.c
index 9e80c98..6955a7d 100644 (file)
--- a/pico/sms.c
+++ b/pico/sms.c
@@ -8,10 +8,8 @@
 /*
  * TODO:
  * - start in a state as if BIOS ran
- * - remaining status flags (OVR/COL)
  * - RAM support in mapper
  * - region support
- * - SN76496 DAC-like usage
  * - H counter
  */
 #include "pico_int.h"
@@ -108,12 +106,12 @@ static unsigned char z80_sms_in(unsigned short a)
       break;
 
     case 0xc0: /* I/O port A and B */
-      d = ~((PicoPad[0] & 0x3f) | (PicoPad[1] << 6));
+      d = ~((PicoIn.pad[0] & 0x3f) | (PicoIn.pad[1] << 6));
       break;
 
     case 0xc1: /* I/O port B and miscellaneous */
       d = (Pico.ms.io_ctl & 0x80) | ((Pico.ms.io_ctl << 1) & 0x40) | 0x30;
-      d |= ~(PicoPad[1] >> 2) & 0x0f;
+      d |= ~(PicoIn.pad[1] >> 2) & 0x0f;
       break;
   }
 
@@ -133,8 +131,9 @@ static void z80_sms_out(unsigned short a, unsigned char d)
 
     case 0x40:
     case 0x41:
-      if (PicoOpt & POPT_EN_PSG)
-        SN76496Write(d);
+      if ((d & 0x90) == 0x90 && PsndPsgLine < Pico.m.scanline)
+        PsndDoPSG(Pico.m.scanline);
+      SN76496Write(d);
       break;
 
     case 0x80:
@@ -255,7 +254,7 @@ void PicoFrameMS(void)
   int lines = is_pal ? 313 : 262;
   int cycles_line = is_pal ? 58020 : 58293; /* (226.6 : 227.7) * 256 */
   int cycles_done = 0, cycles_aim = 0;
-  int skip = PicoSkipFrame;
+  int skip = PicoIn.skipFrame;
   int lines_vis = 192;
   int hint; // Hint counter
   int nmi;
@@ -263,7 +262,7 @@ void PicoFrameMS(void)
 
   PsndStartFrame();
 
-  nmi = (PicoPad[0] >> 7) & 1;
+  nmi = (PicoIn.pad[0] >> 7) & 1;
   if (!Pico.ms.nmi_state && nmi)
     z80_nmi();
   Pico.ms.nmi_state = nmi;
@@ -300,12 +299,16 @@ void PicoFrameMS(void)
       }
     }
 
+    // 224 because of how it's done for MD...
+    if (y == 224 && PsndOut)
+      PsndGetSamplesMS();
+
     cycles_aim += cycles_line;
     cycles_done += z80_run((cycles_aim - cycles_done) >> 8) << 8;
   }
 
-  if (PsndOut)
-    PsndGetSamplesMS();
+  if (PsndOut && PsndPsgLine < lines)
+    PsndDoPSG(lines - 1);
 }
 
 void PicoFrameDrawOnlyMS(void)
@@ -319,3 +322,4 @@ void PicoFrameDrawOnlyMS(void)
     PicoLineMode4(y);
 }
 
+// vim:ts=2:sw=2:expandtab