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e8135fea5a
Plain import of the library parts first. Adaptions to Rockbox will follow. A *lot* of kudos go to Mihaly Horvath for creating this library from his already lightweight cSID-light, mainly for Rockbox. Besides a lot of other things, he made his algorithms integer-only and significantly improved the C64 emulation, so finally RSIDs could be played as well as PSIDs. TinySID was nice for what it is, but this is a quantum leap in SID playback quality for Rockbox. Check for example: https://hvsc.csdb.dk/MUSICIANS/P/Page_Jason/Eighth.sid https://hvsc.csdb.dk/MUSICIANS/J/Jeff/Blowing.sid Change-Id: I353e12fbfd7cd8696b834616e55743e7b844a73e
60 lines
1.9 KiB
C
60 lines
1.9 KiB
C
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#ifdef CRSID_PLATFORM_PC
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int cRSID_loadSIDfile (unsigned char* SIDfileData, char* filename, int maxlen) {
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static signed short Data;
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static signed int SizeCnt;
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static FILE *SIDfile;
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if ( (SIDfile=fopen(filename,"rb")) == NULL ) return CRSID_ERROR_LOAD;
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SizeCnt=0;
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while ( (Data=fgetc(SIDfile)) != EOF ) {
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if (SizeCnt >= maxlen) return CRSID_ERROR_LOAD;
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SIDfileData[SizeCnt] = Data; SizeCnt++;
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}
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fclose(SIDfile);
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return SizeCnt;
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}
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#endif
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cRSID_SIDheader* cRSID_processSIDfile(cRSID_C64instance* C64, unsigned char* filedata, int filesize) {
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int i;
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unsigned short SIDdataOffset;
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cRSID_SIDheader* SIDheader;
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static const char MagicStringPSID[]="PSID";
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//static const char MagicStringRSID[]="RSID";
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C64->SIDheader = SIDheader = (cRSID_SIDheader*) filedata;
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for (i=0x0000; i < 0xA000; ++i) C64->RAMbank[i]=0; //fresh start (maybe some bugged SIDs want 0 at certain RAM-locations)
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for (i=0xC000; i < 0xD000; ++i) C64->RAMbank[i]=0;
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if ( SIDheader->MagicString[0] != 'P' && SIDheader->MagicString[0] != 'R' ) return NULL;
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for (i=1; i < (int)(sizeof(MagicStringPSID)-1); ++i) { if (SIDheader->MagicString[i] != MagicStringPSID[i]) return NULL; }
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C64->RealSIDmode = ( SIDheader->MagicString[0] == 'R' );
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if (SIDheader->LoadAddressH==0 && SIDheader->LoadAddressH==0) { //load-address taken from first 2 bytes of the C64 PRG
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C64->LoadAddress = (filedata[SIDheader->HeaderSize+1]<<8) + (filedata[SIDheader->HeaderSize+0]);
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SIDdataOffset = SIDheader->HeaderSize+2;
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}
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else { //load-adress taken from SID-header
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C64->LoadAddress = (SIDheader->LoadAddressH<<8) + (SIDheader->LoadAddressL);
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SIDdataOffset = SIDheader->HeaderSize;
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}
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for (i=SIDdataOffset; i<filesize; ++i) C64->RAMbank [ C64->LoadAddress + (i-SIDdataOffset) ] = filedata[i];
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i = C64->LoadAddress + (filesize-SIDdataOffset);
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C64->EndAddress = (i<0x10000) ? i : 0xFFFF;
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C64->PSIDdigiMode = ( !C64->RealSIDmode && (SIDheader->ModelFormatStandard & 2) );
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return C64->SIDheader;
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}
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