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r19303 Tuesday 4th December, 2012 at 02:55:17 UTC by David Haywood
neocd, code reduction (nw)
[src/mame/machine]megacdcd.c megacdcd.h megadriv.c

trunk/src/mame/machine/megadriv.c
r19302r19303
1010
1111Cleanup / Rewrite notes:
1212
13On SegaC2 the VDP never turns on the IRQ6 enable register
14  This is because on the real PCB that line of the VDP isn't
15  connected.  Instead the IRQ6 interrupt is triggered by the
16  line that is used to generate the Z80 interrupt on a standard
17  genesis.  (Once, every frame, on screenline 224)
1813
19  I should provide interrupt callback functions for each
20  vdp line state change, which can be configured in the init
21  rather than hardcoding them.
2214
23
2415Known Non-Issues (confirmed on Real Genesis)
2516    Castlevania - Bloodlines (U) [!] - Pause text is missing on upside down level
2617    Blood Shot (E) (M4) [!] - corrupt texture in level 1 is correct...
trunk/src/mame/machine/megacdcd.c
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2424      CDD_RX[i] = 0;
2525   NeoCDCommsWordCount = 0;
2626   NeoCDAssyStatus = 0;
27   NeoCDTrack = 0;
28   NeoCDSectorMin = 0;
29   NeoCDSectorSec = 0;
30   NeoCDSectorFrm = 0;
3127   SCD_CURLBA = 0;
3228   for (int i=0;i<2352;i++)
3329      NeoCDSectorData[i] = 0;
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116112   CDD_RX[9] = checksum;
117113}
118114
115// converts our 16-bit working regs to 8-bit regs and checksums them
119116void lc89510_temp_device::CDD_Export(void)
120117{
121118   CDD_RX[0] = (CDD_STATUS  & 0xff00)>>8;
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277274      CDD_FRAME |= 0x0800;
278275}
279276
277// verify what this is.. the NeoCd emu code only checked the track type but
278// checked it where we put CDD_EXT, not CDD_FRAME (RX[7] vs RX[8] in Export)
279void lc89510_temp_device::CDD_GetTrackType(void)
280{
281   CLEAR_CDD_RESULT
282
283   int track = (CDD_TX[5] & 0xF) + (CDD_TX[4] & 0xF) * 10;
284   int last_track = cdrom_get_last_track(segacd.cd);
285
286   CDD_STATUS &= 0xFF;
287   if(segacd.cd == NULL) // no cd is there, bail out
288      return;
289   CDD_STATUS |= SCD_STATUS;
290
291   if (track > last_track)
292      track = last_track;
293
294   if (track < 1)
295      track = 1;
296
297   if (segacd.toc->tracks[track - 1].trktype != CD_TRACK_AUDIO)
298   {
299      CDD_EXT = 0x08;
300      CDD_FRAME |= 0x0800;
301   }
302
303
304
305}
306
280307UINT32 lc89510_temp_device::getmsf_from_regs(void)
281308{
282309   UINT32 msf = 0;
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631658      case TOCCMD_LENGTH:    CDD_Length();      break;
632659      case TOCCMD_FIRSTLAST: CDD_FirstLast();   break;
633660      case TOCCMD_TRACKADDR: CDD_GetTrackAdr(); break;
661      case 6:                CDD_GetTrackType(); break; // NGCD, might be wrong, make sure Sega CD doesn't hate it
634662      default:               CDD_GetStatus();   break;
635663   }
636664}
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958986   return CDEmuStatus;
959987}
960988
961UINT8* lc89510_temp_device::CDEmuReadQChannel(int SCD_CURLBA)
962{
963//   printf("CDEmuReadQChannel\n");
964   static unsigned char QChannelData[8];
965989
966   if(segacd.cd == NULL) // no cd is there, bail out
967      return QChannelData;
968
969//  SCD_CURLBA
970   switch (CDEmuStatus) {
971      case reading:
972      case playing: {
973
974         UINT32 msf;
975         msf = lba_to_msf_alt(SCD_CURLBA+150);
976
977
978
979         QChannelData[0] = cdrom_get_track(segacd.cd, SCD_CURLBA);
980
981         QChannelData[1] = (msf >> 16)&0xff;
982         QChannelData[2] = (msf >> 8)&0xff;
983         QChannelData[3] = (msf >> 0)&0xff;
984
985         int elapsedlba;
986         elapsedlba = SCD_CURLBA - segacd.toc->tracks[ cdrom_get_track(segacd.cd, SCD_CURLBA) ].physframeofs;
987         msf = lba_to_msf_alt (elapsedlba);
988
989         QChannelData[4] = (msf >> 16)&0xff;
990         QChannelData[5] = (msf >> 8)&0xff;
991         QChannelData[6] = (msf >> 0)&0xff;
992
993         if (QChannelData[0]==1)
994            QChannelData[7] = 0x4;
995         else
996            QChannelData[7] = 0x0;
997
998         break;
999      }
1000      case paused: {
1001         break;
1002      }
1003      default: {
1004         memset(QChannelData, 0, sizeof(QChannelData));
1005      }
1006   }
1007
1008   return QChannelData;
1009}
1010
1011UINT8* lc89510_temp_device::CDEmuReadTOC(INT32 track)
1012{
1013//   printf("CDEmuReadTOC\n");
1014
1015   static unsigned char TOCEntry[4];
1016
1017   if(segacd.cd == NULL)
1018      return TOCEntry;
1019
1020
1021   if (track == -1) {
1022      printf("get first/last track nums\n");
1023      TOCEntry[0] = 1;
1024      TOCEntry[1] = cdrom_get_last_track(segacd.cd);
1025      TOCEntry[2] = 0;
1026      TOCEntry[3] = 0;
1027
1028      return TOCEntry;
1029   }
1030   else if (track == -2) {
1031      printf("get disc length\n");
1032
1033      UINT32 startlba = (segacd.toc->tracks[cdrom_get_last_track(segacd.cd)].physframeofs);
1034      UINT32 startmsf = lba_to_msf_alt( startlba );
1035
1036
1037      TOCEntry[0] = (startmsf >> 16)&0xff;
1038      TOCEntry[1] = (startmsf >> 8)&0xff;
1039      TOCEntry[2] = (startmsf >> 0)&0xff;
1040
1041      TOCEntry[3] = 0;
1042
1043      return TOCEntry;
1044   }
1045   else
1046   {
1047      printf("get track address\n");
1048
1049      int last_track = cdrom_get_last_track(segacd.cd);
1050
1051      if (track > last_track)
1052         track = last_track;
1053
1054      if (track < 1)
1055         track = 1;
1056
1057      UINT32 startlba = (segacd.toc->tracks[track-1].physframeofs);
1058      UINT32 startmsf = lba_to_msf_alt( startlba+150 );
1059
1060      TOCEntry[0] = (startmsf >> 16)&0xff;
1061      TOCEntry[1] = (startmsf >> 8)&0xff;
1062      TOCEntry[2] = (startmsf >> 0)&0xff;
1063      TOCEntry[3] =  track % 10;;
1064   }
1065
1066   return TOCEntry;
1067
1068}
1069
1070990static void CDEmuStartRead()
1071991{
1072992   printf("CDEmuStartRead\n");
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11031023
11041024
11051025
1106void lc89510_temp_device::NeoCDLBAToMSF(const INT32 LBA)
1107{
1108   NeoCDSectorMin = (LBA + CD_FRAMES_PREGAP)                    / CD_FRAMES_MINUTE;
1109   NeoCDSectorSec = (LBA + CD_FRAMES_PREGAP) % CD_FRAMES_MINUTE / CD_FRAMES_SECOND;
1110   NeoCDSectorFrm = (LBA + CD_FRAMES_PREGAP) % CD_FRAMES_SECOND;
1111}
11121026
11131027
11141028void lc89510_temp_device::NeoCDCommsReset()
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13971311         break;
13981312      case CMD_GETTOC: // CDD_Handle_TOC_Commands();
13991313//                              //bprintf(PRINT_ERROR, _T("    CD comms received command %i\n"), CDD_TX[0]);
1400         CDD_RX[1] = CDD_TX[3];
1401          switch (CDD_TX[3]) {
1402
1403
1404
1405            case TOCCMD_CURPOS: { //  CDD_GetPos();
1406               UINT8* ChannelData = CDEmuReadQChannel(SCD_CURLBA);
1407
1408               CDD_RX[2] = ChannelData[1] / 10;
1409               CDD_RX[3] = ChannelData[1] % 10;
1410
1411               CDD_RX[4] = ChannelData[2] / 10;
1412               CDD_RX[5] = ChannelData[2] % 10;
1413
1414               CDD_RX[6] = ChannelData[3] / 10;
1415               CDD_RX[7] = ChannelData[3] % 10;
1416
1417               CDD_RX[8] = ChannelData[7];
1418
1419// //bprintf(PRINT_ERROR, _T("    %02i %02i:%02i:%02i %02i:%02i:%02i %02i\n"), ChannelData[0], ChannelData[1], ChannelData[2], ChannelData[3], ChannelData[4], ChannelData[5], ChannelData[6], ChannelData[7]);
1420
1421               break;
1422            }
1423            case TOCCMD_TRKPOS: { //  CDD_GetTrackPos();
1424               UINT8* ChannelData = CDEmuReadQChannel(SCD_CURLBA);
1425
1426               CDD_RX[2] = ChannelData[4] / 10;
1427               CDD_RX[3] = ChannelData[4] % 10;
1428
1429               CDD_RX[4] = ChannelData[5] / 10;
1430               CDD_RX[5] = ChannelData[5] % 10;
1431
1432               CDD_RX[6] = ChannelData[6] / 10;
1433               CDD_RX[7] = ChannelData[6] % 10;
1434
1435               CDD_RX[8] = ChannelData[7];
1436
1437               break;
1438            }
1439            case TOCCMD_CURTRK: { //  CDD_GetTrack();
1440
1441               UINT8* ChannelData = CDEmuReadQChannel(SCD_CURLBA);
1442
1443               CDD_RX[2] = ChannelData[0] / 10;
1444               CDD_RX[3] = ChannelData[0] % 10;
1445
1446
1447               CDD_RX[8] = ChannelData[7];
1448
1449               break;
1450            }
1451            case TOCCMD_LENGTH: { //  CDD_Length();
1452               UINT8* TOCEntry = CDEmuReadTOC(-2);
1453
1454               CDD_RX[2] = TOCEntry[0] / 10;
1455               CDD_RX[3] = TOCEntry[0] % 10;
1456
1457               CDD_RX[4] = TOCEntry[1] / 10;
1458               CDD_RX[5] = TOCEntry[1] % 10;
1459
1460               CDD_RX[6] = TOCEntry[2] / 10;
1461               CDD_RX[7] = TOCEntry[2] % 10;
1462
1463               break;
1464            }
1465            case TOCCMD_FIRSTLAST: { //  CDD_FirstLast();
1466               UINT8* TOCEntry = CDEmuReadTOC(-1);
1467
1468               CDD_RX[2] = TOCEntry[0] / 10;
1469               CDD_RX[3] = TOCEntry[0] % 10;
1470
1471               CDD_RX[4] = TOCEntry[1] / 10;
1472               CDD_RX[5] = TOCEntry[1] % 10;
1473
1474               break;
1475            }
1476            case TOCCMD_TRACKADDR:   { //  CDD_GetTrackAdr();
1477               NeoCDTrack = CDD_TX[4] * 10 + CDD_TX[5];
1478
1479               UINT8* TOCEntry = CDEmuReadTOC(NeoCDTrack);
1480
1481               CDD_RX[2] = TOCEntry[0] / 10;
1482               CDD_RX[3] = TOCEntry[0] % 10;
1483
1484               CDD_RX[4] = TOCEntry[1] / 10;
1485               CDD_RX[5] = TOCEntry[1] % 10;
1486
1487               CDD_RX[6] = TOCEntry[2] / 10;
1488               CDD_RX[7] = TOCEntry[2] % 10;
1489
1490               // bit 3 of the 1st minutes digit indicates a data track
1491               if (TOCEntry[3] & 4) {
1492                  CDD_RX[6] |= 8;
1493               }
1494
1495               CDD_RX[8] = NeoCDTrack % 10;
1496
1497               break;
1498            }
1499
1500            case 6: {
1501
1502               UINT8* ChannelData = CDEmuReadQChannel(SCD_CURLBA);
1503
1504               CDD_RX[8] = ChannelData[7];
1505
1506               break;
1507            }
1508
1509            case 7: {
1510
1511               // must be 02, 0E, 0F, or 05
1512               CDD_RX[2] = 0;
1513               CDD_RX[3] = 5;
1514
1515               CDD_RX[4] = 0;
1516               CDD_RX[5] = 0;
1517
1518               CDD_RX[6] = 0;
1519               CDD_RX[7] = 0;
1520               break;
1521            }
1522          }
1314   
1315         CDD_Handle_TOC_Commands();
1316         CDD_Export();
15231317         break;
15241318
15251319
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16891483
16901484void lc89510_temp_device::LC8951UpdateHeader() // neocd
16911485{
1692   NeoCDLBAToMSF(SCD_CURLBA);
16931486
16941487   if (LC8951RegistersW[REG_W_CTRL1] & 1) {
16951488
r19302r19303
17031496   } else {
17041497
17051498      // HEAD registers have header
1499      UINT32 msf = lba_to_msf_alt(SCD_CURLBA+150);
17061500
1707      LC8951RegistersR[REG_R_HEAD0] = ((NeoCDSectorMin / 10) << 4) | (NeoCDSectorMin % 10);   // HEAD0
1708      LC8951RegistersR[REG_R_HEAD1] = ((NeoCDSectorSec / 10) << 4) | (NeoCDSectorSec % 10);   // HEAD1
1709      LC8951RegistersR[REG_R_HEAD2] = ((NeoCDSectorFrm / 10) << 4) | (NeoCDSectorFrm % 10);   // HEAD2
1710      LC8951RegistersR[REG_R_HEAD3] = 1;                                       // HEAD3
1501      LC8951RegistersR[REG_R_HEAD0] = to_bcd (((msf & 0x00ff0000)>>16), true);   // HEAD0
1502      LC8951RegistersR[REG_R_HEAD1] = to_bcd (((msf & 0x0000ff00)>>8), true);      // HEAD1
1503      LC8951RegistersR[REG_R_HEAD2] = to_bcd (((msf & 0x000000ff)>>0), true);      // HEAD2
1504      LC8951RegistersR[REG_R_HEAD3] = 0x1;                              // HEAD3
17111505   }
17121506}
17131507
trunk/src/mame/machine/megacdcd.h
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231231   void CDD_Length(void);
232232   void CDD_FirstLast(void);
233233   void CDD_GetTrackAdr(void);
234   void CDD_GetTrackType(void);
234235   UINT32 getmsf_from_regs(void);
235236   void CDD_Play(running_machine &machine);
236237   void CDD_Seek(void);
r19302r19303
296297
297298   INT32 NeoCDAssyStatus;
298299
299   INT32 NeoCDTrack;
300300
301   INT32 NeoCDSectorMin;
302   INT32 NeoCDSectorSec;
303   INT32 NeoCDSectorFrm;
304
305301   bool bNeoCDLoadSector;
306302
307303   INT32 NeoCDDMAAddress1;
r19302r19303
325321   char* LC8915InitTransfer();
326322   void LC8915EndTransfer();
327323   void LC8951Reset();
328   void NeoCDLBAToMSF(const INT32 LBA);
329324   void neocd_cdd_tx_w(UINT8 data);
330325   UINT8 neocd_cdd_rx_r();
331326   void NeoCDCommsReset();
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335330   UINT32 SekReadByte(UINT32 a);
336331   UINT32 SekReadWord(UINT32 a);
337332
338   UINT8* CDEmuReadQChannel(int SCD_CURLBA);
339   UINT8* CDEmuReadTOC(INT32 track);
340333   INT32 CDEmuLoadSector(INT32 LBA, char* pBuffer);
341334   void set_DMA_regs(int offset, UINT16 wordValue);
342335   void reset_NeoCd(void);

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