Esidplay: 6510_.cpp Source File

00001 //
00002 // 1997/09/27 21:31:51
00003 // 
00004 // --------------------------------------------------------------------------
00005 // Copyright (c) 1994-1997 Michael Schwendt. All rights reserved.
00006 //
00007 // Redistribution and use  in source and  binary forms, either  unchanged or
00008 // modified, are permitted provided that the following conditions are met:
00009 //
00010 // (1)  Redistributions  of  source  code  must  retain  the above copyright
00011 // notice, this list of conditions and the following disclaimer.
00012 //
00013 // (2) Redistributions  in binary  form must  reproduce the  above copyright
00014 // notice,  this  list  of  conditions  and  the following disclaimer in the
00015 // documentation and/or other materials provided with the distribution.
00016 //
00017 // THIS SOFTWARE  IS PROVIDED  BY THE  AUTHOR ``AS  IS'' AND  ANY EXPRESS OR
00018 // IMPLIED  WARRANTIES,  INCLUDING,   BUT  NOT  LIMITED   TO,  THE   IMPLIED
00019 // WARRANTIES OF MERCHANTABILITY  AND FITNESS FOR  A PARTICULAR PURPOSE  ARE
00020 // DISCLAIMED.  IN NO EVENT SHALL  THE AUTHOR OR CONTRIBUTORS BE LIABLE  FOR
00021 // ANY DIRECT,  INDIRECT, INCIDENTAL,  SPECIAL, EXEMPLARY,  OR CONSEQUENTIAL
00022 // DAMAGES (INCLUDING, BUT NOT  LIMITED TO, PROCUREMENT OF  SUBSTITUTE GOODS
00023 // OR SERVICES;  LOSS OF  USE, DATA,  OR PROFITS;  OR BUSINESS INTERRUPTION)
00024 // HOWEVER  CAUSED  AND  ON  ANY  THEORY  OF LIABILITY, WHETHER IN CONTRACT,
00025 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING  IN
00026 // ANY  WAY  OUT  OF  THE  USE  OF  THIS  SOFTWARE,  EVEN  IF ADVISED OF THE
00027 // POSSIBILITY OF SUCH DAMAGE.
00028 // --------------------------------------------------------------------------
00029 //
00030 // MOS-6510 Interpreter. Known bugs, missing features, incompatibilities:
00031 //
00032 //  - No support for code execution in Basic-ROM/Kernal-ROM.
00033 //    Only execution of code in RAM is allowed.
00034 //  - Probably inconsistent emulation of illegal instructions part 3.
00035 //  - No detection of deadlocks.
00036 //  - Faked RTI (= RTS).
00037 //  - Anybody knows, whether it is ``Kernel'' instead of ``Kernal'' ?
00038 //    Perhaps it is a proper name invented by CBM ?
00039 //    It is spelled ``Kernal'' in nearly every C64 documentation !
00040 //
00041 
00042 #include "6510_.h"
00043 #include "emucfg.h"
00044 
00045 #ifdef __SYMBIAN32__
00046 #include <e32base.h>
00047 #else
00048 #include <stdlib.h>
00049 #endif
00050 
00051 //inline void RTS_();               // proto
00052 
00053 
00054 
00055 
00056 
00057 C6510::C6510()
00061         :stackIsOkay(true)
00062         ,memoryMode(MPU_TRANSPARENT_ROM)
00063         ,iFakeRndSeed(0)
00064         {
00065         CTOR(C6510);
00066 
00067         // no need for initialising member data to zero here.
00068         // that is done by the CBase class
00069 
00070         // Use pointers to allow plain-memory modifications.
00071         readData = &C6510::readData_bs;
00072         writeData = &C6510::writeData_bs;
00073 
00074 // --------------------------------------------------------------------------
00075 
00076 
00077         //
00078         // initialise 6510 instructions array
00079         //
00080         int i=0;
00081          
00082         instrList[i++] = &C6510::BRK_;
00083         instrList[i++] = &C6510::ORA_indx;
00084         instrList[i++] = &C6510::ILL_TILT;
00085         instrList[i++] = &C6510::ASLORA_indx;
00086         instrList[i++] = &C6510::ILL_2NOP;
00087         instrList[i++] = &C6510::ORA_zp;
00088         instrList[i++] = &C6510::ASL_zp;
00089         instrList[i++] = &C6510::ASLORA_zp;
00090         instrList[i++] = &C6510::PHP_;
00091         instrList[i++] = &C6510::ORA_imm;
00092         instrList[i++] = &C6510::ASL_AC;
00093         instrList[i++] = &C6510::ILL_0B;
00094         instrList[i++] = &C6510::ILL_3NOP;
00095         instrList[i++] = &C6510::ORA_abso;
00096         instrList[i++] = &C6510::ASL_abso;
00097         instrList[i++] = &C6510::ASLORA_abso;
00098         instrList[i++] = &C6510::BPL_;
00099         instrList[i++] = &C6510::ORA_indy;
00100         instrList[i++] = &C6510::ILL_TILT;
00101         instrList[i++] = &C6510::ASLORA_indy;
00102         instrList[i++] = &C6510::ILL_2NOP;
00103         instrList[i++] = &C6510::ORA_zpx;
00104         instrList[i++] = &C6510::ASL_zpx;
00105         instrList[i++] = &C6510::ASLORA_zpx;
00106         instrList[i++] = &C6510::CLC_;
00107         instrList[i++] = &C6510::ORA_absy;
00108         instrList[i++] = &C6510::ILL_1NOP;
00109         instrList[i++] = &C6510::ASLORA_absy;
00110         instrList[i++] = &C6510::ILL_3NOP;
00111         instrList[i++] = &C6510::ORA_absx;
00112         instrList[i++] = &C6510::ASL_absx;
00113         instrList[i++] = &C6510::ASLORA_absx;
00114         instrList[i++] = &C6510::JSR_;
00115         instrList[i++] = &C6510::AND_indx;
00116         instrList[i++] = &C6510::ILL_TILT;
00117         instrList[i++] = &C6510::ROLAND_indx;
00118         instrList[i++] = &C6510::BIT_zp;
00119         instrList[i++] = &C6510::AND_zp;
00120         instrList[i++] = &C6510::ROL_zp;
00121         instrList[i++] = &C6510::ROLAND_zp;
00122         instrList[i++] = &C6510::PLP_;
00123         instrList[i++] = &C6510::AND_imm;
00124         instrList[i++] = &C6510::ROL_AC;
00125         instrList[i++] = &C6510::ILL_0B;
00126         instrList[i++] = &C6510::BIT_abso;
00127         instrList[i++] = &C6510::AND_abso;
00128         instrList[i++] = &C6510::ROL_abso;
00129         instrList[i++] = &C6510::ROLAND_abso;
00130         instrList[i++] = &C6510::BMI_;
00131         instrList[i++] = &C6510::AND_indy;
00132         instrList[i++] = &C6510::ILL_TILT;
00133         instrList[i++] = &C6510::ROLAND_indy;
00134         instrList[i++] = &C6510::ILL_2NOP;
00135         instrList[i++] = &C6510::AND_zpx;
00136         instrList[i++] = &C6510::ROL_zpx;
00137         instrList[i++] = &C6510::ROLAND_zpx;
00138         instrList[i++] = &C6510::SEC_;
00139         instrList[i++] = &C6510::AND_absy;
00140         instrList[i++] = &C6510::ILL_1NOP;
00141         instrList[i++] = &C6510::ROLAND_absy;
00142         instrList[i++] = &C6510::ILL_3NOP;
00143         instrList[i++] = &C6510::AND_absx;
00144         instrList[i++] = &C6510::ROL_absx;
00145         instrList[i++] = &C6510::ROLAND_absx,
00146         // 0x40
00147         instrList[i++] = &C6510::RTI_;
00148         instrList[i++] = &C6510::EOR_indx;
00149         instrList[i++] = &C6510::ILL_TILT;
00150         instrList[i++] = &C6510::LSREOR_indx;
00151         instrList[i++] = &C6510::ILL_2NOP;
00152         instrList[i++] = &C6510::EOR_zp;
00153         instrList[i++] = &C6510::LSR_zp;
00154         instrList[i++] = &C6510::LSREOR_zp;
00155         instrList[i++] = &C6510::PHA_;
00156         instrList[i++] = &C6510::EOR_imm;
00157         instrList[i++] = &C6510::LSR_AC;
00158         instrList[i++] = &C6510::ILL_4B;
00159         instrList[i++] = &C6510::JMP_;
00160         instrList[i++] = &C6510::EOR_abso;
00161         instrList[i++] = &C6510::LSR_abso;
00162         instrList[i++] = &C6510::LSREOR_abso;
00163         instrList[i++] = &C6510::BVC_;
00164         instrList[i++] = &C6510::EOR_indy;
00165         instrList[i++] = &C6510::ILL_TILT;
00166         instrList[i++] = &C6510::LSREOR_indy;
00167         instrList[i++] = &C6510::ILL_2NOP;
00168         instrList[i++] = &C6510::EOR_zpx;
00169         instrList[i++] = &C6510::LSR_zpx;
00170         instrList[i++] = &C6510::LSREOR_zpx;
00171         instrList[i++] = &C6510::CLI_;
00172         instrList[i++] = &C6510::EOR_absy;
00173         instrList[i++] = &C6510::ILL_1NOP;
00174         instrList[i++] = &C6510::LSREOR_absy;
00175         instrList[i++] = &C6510::ILL_3NOP;
00176         instrList[i++] = &C6510::EOR_absx;
00177         instrList[i++] = &C6510::LSR_absx;
00178         instrList[i++] = &C6510::LSREOR_absx;
00179         instrList[i++] = &C6510::RTS_;
00180         instrList[i++] = &C6510::ADC_indx;
00181         instrList[i++] = &C6510::ILL_TILT;
00182         instrList[i++] = &C6510::RORADC_indx;
00183         instrList[i++] = &C6510::ILL_2NOP;
00184         instrList[i++] = &C6510::ADC_zp;
00185         instrList[i++] = &C6510::ROR_zp;
00186         instrList[i++] = &C6510::RORADC_zp;
00187         instrList[i++] = &C6510::PLA_;
00188         instrList[i++] = &C6510::ADC_imm;
00189         instrList[i++] = &C6510::ROR_AC;
00190         instrList[i++] = &C6510::ILL_6B;
00191         instrList[i++] = &C6510::JMP_vec;
00192         instrList[i++] = &C6510::ADC_abso;
00193         instrList[i++] = &C6510::ROR_abso;
00194         instrList[i++] = &C6510::RORADC_abso;
00195         instrList[i++] = &C6510::BVS_;
00196         instrList[i++] = &C6510::ADC_indy;
00197         instrList[i++] = &C6510::ILL_TILT;
00198         instrList[i++] = &C6510::RORADC_indy;
00199         instrList[i++] = &C6510::ILL_2NOP;
00200         instrList[i++] = &C6510::ADC_zpx;
00201         instrList[i++] = &C6510::ROR_zpx;
00202         instrList[i++] = &C6510::RORADC_zpx;
00203         instrList[i++] = &C6510::SEI_;
00204         instrList[i++] = &C6510::ADC_absy;
00205         instrList[i++] = &C6510::ILL_1NOP;
00206         instrList[i++] = &C6510::RORADC_absy;
00207         instrList[i++] = &C6510::ILL_3NOP;
00208         instrList[i++] = &C6510::ADC_absx;
00209         instrList[i++] = &C6510::ROR_absx;
00210         instrList[i++] = &C6510::RORADC_absx;
00211         // 0x80
00212         instrList[i++] = &C6510::ILL_2NOP;
00213         instrList[i++] = &C6510::STA_indx;
00214         instrList[i++] = &C6510::ILL_2NOP;
00215         instrList[i++] = &C6510::ILL_83;
00216         instrList[i++] = &C6510::STY_zp;
00217         instrList[i++] = &C6510::STA_zp;
00218         instrList[i++] = &C6510::STX_zp;
00219         instrList[i++] = &C6510::ILL_87;
00220         instrList[i++] = &C6510::DEY_;
00221         instrList[i++] = &C6510::ILL_2NOP;
00222         instrList[i++] = &C6510::TXA_;
00223         instrList[i++] = &C6510::ILL_8B;
00224         instrList[i++] = &C6510::STY_abso;
00225         instrList[i++] = &C6510::STA_abso;
00226         instrList[i++] = &C6510::STX_abso;
00227         instrList[i++] = &C6510::ILL_8F;
00228         instrList[i++] = &C6510::BCC_;
00229         instrList[i++] = &C6510::STA_indy;
00230         instrList[i++] = &C6510::ILL_TILT;
00231         instrList[i++] = &C6510::ILL_93;
00232         instrList[i++] = &C6510::STY_zpx;
00233         instrList[i++] = &C6510::STA_zpx;
00234         instrList[i++] = &C6510::STX_zpy;
00235         instrList[i++] = &C6510::ILL_97;
00236         instrList[i++] = &C6510::TYA_;
00237         instrList[i++] = &C6510::STA_absy;
00238         instrList[i++] = &C6510::TXS_;
00239         instrList[i++] = &C6510::ILL_9B;
00240         instrList[i++] = &C6510::ILL_9C;
00241         instrList[i++] = &C6510::STA_absx;
00242         instrList[i++] = &C6510::ILL_9E;
00243         instrList[i++] = &C6510::ILL_9F;
00244         instrList[i++] = &C6510::LDY_imm;
00245         instrList[i++] = &C6510::LDA_indx;
00246         instrList[i++] = &C6510::LDX_imm;
00247         instrList[i++] = &C6510::ILL_A3;
00248         instrList[i++] = &C6510::LDY_zp;
00249         instrList[i++] = &C6510::LDA_zp;
00250         instrList[i++] = &C6510::LDX_zp;
00251         instrList[i++] = &C6510::ILL_A7;
00252         instrList[i++] = &C6510::TAY_;
00253         instrList[i++] = &C6510::LDA_imm;
00254         instrList[i++] = &C6510::TAX_;
00255         instrList[i++] = &C6510::ILL_1NOP;
00256         instrList[i++] = &C6510::LDY_abso;
00257         instrList[i++] = &C6510::LDA_abso;
00258         instrList[i++] = &C6510::LDX_abso;
00259         instrList[i++] = &C6510::ILL_AF;
00260         instrList[i++] = &C6510::BCS_;
00261         instrList[i++] = &C6510::LDA_indy;
00262         instrList[i++] = &C6510::ILL_TILT;
00263         instrList[i++] = &C6510::ILL_B3;
00264         instrList[i++] = &C6510::LDY_zpx;
00265         instrList[i++] = &C6510::LDA_zpx;
00266         instrList[i++] = &C6510::LDX_zpy;
00267         instrList[i++] = &C6510::ILL_B7;
00268         instrList[i++] = &C6510::CLV_;
00269         instrList[i++] = &C6510::LDA_absy;
00270         instrList[i++] = &C6510::TSX_;
00271         instrList[i++] = &C6510::ILL_BB;
00272         instrList[i++] = &C6510::LDY_absx;
00273         instrList[i++] = &C6510::LDA_absx;
00274         instrList[i++] = &C6510::LDX_absy;
00275         instrList[i++] = &C6510::ILL_BF;
00276         // 0xC0
00277         instrList[i++] = &C6510::CPY_imm;
00278         instrList[i++] = &C6510::CMP_indx;
00279         instrList[i++] = &C6510::ILL_2NOP;
00280         instrList[i++] = &C6510::DECCMP_indx;
00281         instrList[i++] = &C6510::CPY_zp;
00282         instrList[i++] = &C6510::CMP_zp;
00283         instrList[i++] = &C6510::DEC_zp;
00284         instrList[i++] = &C6510::DECCMP_zp;
00285         instrList[i++] = &C6510::INY_;
00286         instrList[i++] = &C6510::CMP_imm;
00287         instrList[i++] = &C6510::DEX_;
00288         instrList[i++] = &C6510::ILL_CB;
00289         instrList[i++] = &C6510::CPY_abso;
00290         instrList[i++] = &C6510::CMP_abso;
00291         instrList[i++] = &C6510::DEC_abso;
00292         instrList[i++] = &C6510::DECCMP_abso;
00293         instrList[i++] = &C6510::BNE_;
00294         instrList[i++] = &C6510::CMP_indy;
00295         instrList[i++] = &C6510::ILL_TILT;
00296         instrList[i++] = &C6510::DECCMP_indy;
00297         instrList[i++] = &C6510::ILL_2NOP;
00298         instrList[i++] = &C6510::CMP_zpx;
00299         instrList[i++] = &C6510::DEC_zpx;
00300         instrList[i++] = &C6510::DECCMP_zpx;
00301         instrList[i++] = &C6510::CLD_;
00302         instrList[i++] = &C6510::CMP_absy;
00303         instrList[i++] = &C6510::ILL_1NOP;
00304         instrList[i++] = &C6510::DECCMP_absy;
00305         instrList[i++] = &C6510::ILL_3NOP;
00306         instrList[i++] = &C6510::CMP_absx;
00307         instrList[i++] = &C6510::DEC_absx;
00308         instrList[i++] = &C6510::DECCMP_absx;
00309         instrList[i++] = &C6510::CPX_imm;
00310         instrList[i++] = &C6510::SBC_indx;
00311         instrList[i++] = &C6510::ILL_2NOP;
00312         instrList[i++] = &C6510::INCSBC_indx;
00313         instrList[i++] = &C6510::CPX_zp;
00314         instrList[i++] = &C6510::SBC_zp;
00315         instrList[i++] = &C6510::INC_zp;
00316         instrList[i++] = &C6510::INCSBC_zp;
00317         instrList[i++] = &C6510::INX_;
00318         instrList[i++] = &C6510::SBC_imm;
00319         instrList[i++] = &C6510::NOP_;
00320         instrList[i++] = &C6510::ILL_EB;
00321         instrList[i++] = &C6510::CPX_abso;
00322         instrList[i++] = &C6510::SBC_abso;
00323         instrList[i++] = &C6510::INC_abso;
00324         instrList[i++] = &C6510::INCSBC_abso;
00325         instrList[i++] = &C6510::BEQ_;
00326         instrList[i++] = &C6510::SBC_indy;
00327         instrList[i++] = &C6510::ILL_TILT;
00328         instrList[i++] = &C6510::INCSBC_indy;
00329         instrList[i++] = &C6510::ILL_2NOP;
00330         instrList[i++] = &C6510::SBC_zpx;
00331         instrList[i++] = &C6510::INC_zpx;
00332         instrList[i++] = &C6510::INCSBC_zpx;
00333         instrList[i++] = &C6510::SED_;
00334         instrList[i++] = &C6510::SBC_absy;
00335         instrList[i++] = &C6510::ILL_1NOP;
00336         instrList[i++] = &C6510::INCSBC_absy;
00337         instrList[i++] = &C6510::ILL_3NOP;
00338         instrList[i++] = &C6510::SBC_absx;
00339         instrList[i++] = &C6510::INC_absx;
00340         instrList[i++] = &C6510::INCSBC_absx;
00341         
00342         if(i!=256)
00343                 {
00344 //              printf("C6510 init error\n"); /// @todo remove
00345 #if defined(__SYMBIAN32__)
00346                 User::Leave(-1);
00347 #else
00348                 exit(-1);
00349 #endif
00350                 }
00351                 
00352           
00353         }
00354 
00355 
00356 C6510::~C6510()
00360         {
00361         DTOR(C6510);
00362         }
00363 
00364 // --------------------------------------------------------------------------
00365 
00366 
00367 bool C6510::c64memAlloc()
00368 {
00370 
00371         c64mem1 = c64ramBuf;
00372         c64mem2 = c64romBuf;
00373         return true;
00374 }
00375 
00376 
00377 void C6510::initInterpreter(int inMemoryMode)
00378 {
00379         memoryMode = inMemoryMode;
00380         if (memoryMode == MPU_TRANSPARENT_ROM)
00381         {
00382                 readData = &C6510::readData_transp;
00383                 writeData = &C6510::writeData_bs;
00384                 instrList[0x20] = &C6510::JSR_transp;
00385                 instrList[0x4C] = &C6510::JMP_transp;
00386                 instrList[0x6C] = &C6510::JMP_vec_transp;
00387                 // Make the memory buffers accessible to the whole emulator engine.
00388                 // Use two distinct 64KB memory areas.
00389                 c64mem1 = c64ramBuf;
00390                 c64mem2 = c64romBuf;
00391         }
00392         else if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00393         {
00394                 readData = &C6510::readData_plain;
00395                 writeData = &C6510::writeData_plain;
00396                 instrList[0x20] = &C6510::JSR_plain;
00397                 instrList[0x4C] = &C6510::JMP_plain;
00398                 instrList[0x6C] = &C6510::JMP_vec_plain;
00399                 // Make the memory buffers accessible to the whole emulator engine.
00400                 // Use a single 64KB memory area.
00401                 c64mem2 = (c64mem1 = c64ramBuf);
00402         }
00403         else  // if (memoryMode == MPU_BANK_SWITCHING)
00404         {
00405                 readData = &C6510::readData_bs;
00406                 writeData = &C6510::writeData_bs;
00407                 instrList[0x20] = &C6510::JSR_;
00408                 instrList[0x4C] = &C6510::JMP_;
00409                 instrList[0x6C] = &C6510::JMP_vec;
00410                 // Make the memory buffers accessible to the whole emulator engine.
00411                 // Use two distinct 64KB memory areas.
00412                 c64mem1 = c64ramBuf;
00413                 c64mem2 = c64romBuf;
00414         }
00415         bankSelReg = c64ramBuf+1;  // extra pointer
00416         // Set code execution segment to RAM.
00417         pPCbase = c64ramBuf;
00418         pPCend = c64ramBuf+65536;
00419 }
00420 
00421 
00422 void C6510::c64memReset(int clockSpeed, ubyte randomSeed)
00423         {
00424         iFakeRndSeed = (ubyte)(iFakeRndSeed*13+randomSeed);
00425         fakeReadTimer = iFakeRndSeed;
00426         
00427         if ((c64mem1 != 0) && (c64mem2 != 0))
00428         {
00429                 c64mem1[0] = 0x2F;
00430                 // defaults: Basic-ROM on, Kernal-ROM on, I/O on
00431                 c64mem1[1] = 0x07;
00432                 evalBankSelect();
00433                 
00434                 // CIA-Timer A $DC04/5 = $4025 PAL, $4295 NTSC
00435                 if (clockSpeed == SIDTUNE_CLOCK_NTSC)
00436                 {
00437                         c64mem1[0x02a6] = 0;     // NTSC
00438                         c64mem2[0xdc04] = 0x95;
00439                         c64mem2[0xdc05] = 0x42;
00440                 }
00441                 else  // if (clockSpeed == SIDTUNE_CLOCK_PAL)
00442                 {
00443                         c64mem1[0x02a6] = 1;     // PAL
00444                         c64mem2[0xdc04] = 0x25;
00445                         c64mem2[0xdc05] = 0x40;
00446                 }
00447                 
00448                 // fake VBI-interrupts that do $D019, BMI ...
00449                 c64mem2[0xd019] = 0xff;
00450                 
00451                 // software vectors
00452                 // IRQ to $EA31
00453                 c64mem1[0x0314] = 0x31;
00454                 c64mem1[0x0315] = 0xea;
00455                 // BRK to $FE66
00456                 c64mem1[0x0316] = 0x66;
00457                 c64mem1[0x0317] = 0xfe;
00458                 // NMI to $FE47
00459                 c64mem1[0x0318] = 0x47;
00460                 c64mem1[0x0319] = 0xfe;
00461                 
00462                 // hardware vectors 
00463                 if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00464                 {
00465                         c64mem1[0xff48] = 0x6c;
00466                         c64mem1[0xff49] = 0x14;
00467                         c64mem1[0xff4a] = 0x03;
00468                         c64mem1[0xfffa] = 0xf8;
00469                         c64mem1[0xfffb] = 0xff;
00470                         c64mem1[0xfffe] = 0x48;
00471                         c64mem1[0xffff] = 0xff;
00472                 }
00473                 else
00474                 {
00475                         // NMI to $FE43
00476                         c64mem1[0xfffa] = 0x43;
00477                         c64mem1[0xfffb] = 0xfe;
00478                         // RESET to $FCE2
00479                         c64mem1[0xfffc] = 0xe2;
00480                         c64mem1[0xfffd] = 0xfc;
00481                         // IRQ to $FF48
00482                         c64mem1[0xfffe] = 0x48;
00483                         c64mem1[0xffff] = 0xff;
00484                 }
00485                 
00486                 // clear SID
00487                 for ( int i = 0; i < 0x1d; i++ )
00488                 {
00489                         c64mem2[0xd400 +i] = 0;
00490                 }
00491                 // default Mastervolume, no filter
00492                 c64mem2[0xd418] = (sidLastValue = 0x0f);
00493         }
00494 }
00495 
00496 
00497 void C6510::c64memClear()
00498 {
00499         // Clear entire RAM and ROM.
00500 #if defined(__SYMBIAN32__)
00501 // 
00502 // use built in Mem functions for Epoc.
00503 // They are much faster than looping 65536 times
00504 // on byte-by-byte basis.
00505 // 
00506         Mem::FillZ((TAny*)c64mem1, 0x10000);
00507         if (memoryMode != MPU_PLAYSID_ENVIRONMENT)
00508                 {
00509                 Mem::FillZ((TAny*)c64mem2, 0x10000);
00510                 }
00511         sidLastValue = 0;
00512 
00513         if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00514         {
00515                 Mem::Fill((TAny*)&c64mem1[0xE000], (0x10000-0xE000), 0x40);
00516         }
00517         else
00518         {
00519                 // Fill Basic-ROM address space with RTS instructions.
00520                 Mem::Fill((TAny*)&c64mem2[0xA000], (0xC000-0xA000), 0x60);
00521 
00522                 // Fill Kernal-ROM address space with RTI instructions.
00523                 Mem::Fill((TAny*)&c64mem2[0xE000], (0x10000-0xE000), 0x40);
00524 
00525         }
00526 #else
00527         for ( udword i = 0; i < 0x10000; i++ )
00528         {
00529                 c64mem1[i] = 0; 
00530                 if (memoryMode != MPU_PLAYSID_ENVIRONMENT)
00531                 {
00532                         c64mem2[i] = 0; 
00533                 }
00534                 sidLastValue = 0;
00535         }
00536         if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00537         {
00538                 // Fill Kernal-ROM address space with RTI instructions.
00539                 for ( udword j = 0xE000; j < 0x10000; j++ )
00540                 {
00541                         c64mem1[j] = 0x40;
00542                 }
00543         }
00544         else
00545         {
00546                 // Fill Basic-ROM address space with RTS instructions.
00547                 for ( udword j1 = 0xA000; j1 < 0xC000; j1++ )
00548                 {
00549                         c64mem2[j1] = 0x60;
00550                 }
00551                 // Fill Kernal-ROM address space with RTI instructions.
00552                 for ( udword j2 = 0xE000; j2 < 0x10000; j2++ )
00553                 {
00554                         c64mem2[j2] = 0x40;
00555                 }
00556         }
00557 #endif
00558 }
00559 
00560 
00561 bool C6510::interpreter(uword p, ubyte ramrom, ubyte a, ubyte x, ubyte y)
00562 {
00563         if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00564         {
00565                 AC = a;
00566                 XR = 0;
00567                 YR = 0;
00568         }
00569         else
00570         {
00571                 *bankSelReg = ramrom;
00572                 evalBankSelect();
00573                 AC = a;
00574                 XR = x;
00575                 YR = y;
00576         }
00577 
00578         // Set program-counter (pointer instead of raw PC).
00579         pPC = pPCbase+p;
00580         
00581         resetSP();
00582         clearSR();
00583         sidKeysOff[4] = (sidKeysOff[4+7] = (sidKeysOff[4+14] = false));
00584         sidKeysOn[4] = (sidKeysOn[4+7] = (sidKeysOn[4+14] = false));
00585         
00586         do
00587         { 
00588         // AlfredH 23. Aug 2001:
00589         //
00590         // Nasty bug fixed here where pPC was not updated
00591         // until *after* the instruction method was called !
00592         //
00593                 const ubyte instr = *(pPC++);
00594                 (this->*instrList[instr])();
00595         }
00596         while (stackIsOkay&&(pPC<pPCend));
00597 
00598         return true;
00599 }
00600 
00601 
00602 //  Input: A 16-bit effective address
00603 // Output: A default bank-select value for $01.
00604 ubyte C6510::c64memRamRom( uword address )
00605 { 
00606         if (memoryMode == MPU_PLAYSID_ENVIRONMENT)
00607         {
00608                 return 4;  // RAM only, but special I/O mode
00609         }
00610         else
00611         {
00612                 if ( address < 0xa000 )
00613                 {
00614                         return 7;  // Basic-ROM, Kernal-ROM, I/O
00615                 }
00616                 else if ( address < 0xd000 )
00617                 {
00618                         return 6;  // Kernal-ROM, I/O
00619                 }
00620                 else if ( address >= 0xe000 )
00621                 {
00622                         return 5;  // I/O only
00623                 }
00624                 else
00625                 {
00626                         return 4;  // RAM only
00627                 }
00628         }
00629 }