offs_t cop420_disassembler::disassemble(std::ostream &stream, offs_t pc, const data_buffer &opcodes, const data_buffer ¶ms)
{
uint8_t opcode = opcodes.r8(pc);
uint8_t next_opcode = opcodes.r8(pc+1);
uint16_t address;
uint32_t flags = 0;
int bytes = 1;
if ((opcode >= 0x80 && opcode <= 0xBE) || (opcode >= 0xC0 && opcode <= 0xFE))
{
int page = pc >> 6;
if (page == 2 || page == 3) //JP pages 2,3
{
address = (uint16_t)((pc & 0x380) | (opcode & 0x7F));
util::stream_format(stream, "JP %03X", address);
}
else
{
if ((opcode & 0xC0) == 0xC0) //JP other pages
{
address = (uint16_t)((pc & 0x3C0) | (opcode & 0x3F));
util::stream_format(stream, "JP %03X", address);
}
else //JSRP
{
address = (uint16_t)(0x80 | (opcode & 0x3F));
util::stream_format(stream, "JSRP %03X", address);
flags = STEP_OVER;
}
}
}
offs_t capricorn_disassembler::param_dr_lit(std::ostream &stream, offs_t pc, const data_buffer &opcodes)
{
stream << "DR,=";
// Here we assume that multi-byte instructions operate on 2 bytes because we
// have no way of knowing how many they are (the actual number of bytes is
// dynamically determined by the value of DRP register at run-time)
unsigned bytes = BIT(opcodes.r8(pc), 0) ? 2 : 1;
for (unsigned i = 1; i <= bytes; i++) {
util::stream_format(stream, "$%02x ", opcodes.r8(pc+i));
}
return bytes;
}
offs_t capricorn_disassembler::disassemble(std::ostream &stream, offs_t pc, const data_buffer &opcodes, const data_buffer ¶ms)
{
const dis_entry_t *p;
uint8_t opcode = opcodes.r8(pc);
for (p = dis_table; p->m_op_mask; p++) {
if ((opcode & p->m_op_mask) == p->m_opcode) {
offs_t res = 1 | p->m_dasm_flags | SUPPORTED;
stream << p->m_mnemonic;
if (p->m_has_mb) {
stream << (BIT(opcode, 0) ? 'M' : 'B');
}
if (p->m_addr_mode != '\0') {
stream << p->m_addr_mode;
}
if (p->m_param_fn != nullptr) {
stream << " ";
res += (this->*(p->m_param_fn))(stream, pc, opcodes);
}
return res;
}
}
// Unknown opcode
stream << "???";
return 1 | SUPPORTED;
}
offs_t capricorn_disassembler::param_jmp_off(std::ostream &stream, offs_t pc, const data_buffer &opcodes)
{
uint16_t off = opcodes.r8(pc+1);
if (BIT(off, 7)) {
off -= 0x100;
}
util::stream_format(stream, "$%04x", (pc + 2 + off) & 0xffff);
return 1;
}
offs_t capricorn_disassembler::param_dr_id_ar(std::ostream &stream, offs_t pc, const data_buffer &opcodes)
{
stream << "DR," << (BIT(opcodes.r8(pc), 1) ? '-' : '+') << "AR";
return 0;
}
offs_t capricorn_disassembler::param_arp_drp(std::ostream &stream, offs_t pc, const data_buffer &opcodes)
{
stream << "R";
util::stream_format(stream, "%02o", opcodes.r8(pc) & 0x3f);
return 0;
}
offs_t saturn_disassembler::disassemble(std::ostream &stream, offs_t pc, const data_buffer &opcodes, const data_buffer ¶ms)
{
int adr=0;
int cont=1; // operation still not complete disassembled
char bin[10]; int binsize=0; // protocollizing fetched nibbles
char number[17];
const OPCODE *level=opcs[0]; //pointer to current digit
int op; // currently fetched nibble
offs_t pos = pc;
int i,c,v;
int mnemonics_bank = m_config->get_nonstandard_mnemonics_mode() ? 1 : 0;
while (cont)
{
op = opcodes.r8(pos++) & 0xf;
level+=op;
switch (level->sel) {
case Illegal:
cont=0;
bin[binsize++]=number_2_hex[op];
bin[binsize]=0;
util::stream_format(stream, "???%s",bin);
break;
default:
bin[binsize++]=number_2_hex[op];
switch (level->adr) {
case AdrNone: break;
case AdrA:
adr=field_adr_a[op];
break;
case AdrAF:
adr=field_adr_af[op];
break;
case AdrB:
adr=field_adr_b[op&7];
break;
default:
cont = 0;
bin[binsize++]=number_2_hex[op];
bin[binsize]=0;
util::stream_format(stream, "???%s",bin);
break;
}
break;
case Complete:
cont=0;
switch (level->adr==AdrNone?adr:level->adr) {
case AdrNone:
stream << mnemonics[level->mnemonic][mnemonics_bank];
break;
case Imm:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], opcodes.r8(pos++));
break;
case ImmCount:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], opcodes.r8(pos++)+1);
break;
case AdrImmCount:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], field_2_string(adr), opcodes.r8(pos++)+1);
break;
case AdrCount: // mnemonics have string %s for address field
snprintf(number,sizeof(number),"%x",opcodes.r8(pos++)+1);
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], number);
break;
case Imm2:
v=opcodes.r8(pos++);
v|=opcodes.r8(pos++)<<4;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], v);
break;
case Imm4:
v=opcodes.r8(pos++);
v|=opcodes.r8(pos++)<<4;
v|=opcodes.r8(pos++)<<8;
v|=opcodes.r8(pos++)<<12;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], v);
break;
case Imm5:
v=opcodes.r8(pos++);
v|=opcodes.r8(pos++)<<4;
v|=opcodes.r8(pos++)<<8;
v|=opcodes.r8(pos++)<<12;
v|=opcodes.r8(pos++)<<16;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], v);
break;
case ImmCload:
c=i=opcodes.r8(pos++) & 0xf;
number[i+1]=0;
for (;i>=0; i--) number[i]=number_2_hex[opcodes.r8(pos++) & 0xf];
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c+1, number);
break;
case Dis3:
SATURN_PEEKOP_DIS12(v);
c=(pc+pos-3+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c );
break;
case Dis3Call:
SATURN_PEEKOP_DIS12(v);
c=(pc+pos+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c );
break;
case Dis4:
SATURN_PEEKOP_DIS16(v);
c=(pc+pos-4+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c );
break;
case Dis4Call:
SATURN_PEEKOP_DIS16(v);
c=(pc+pos+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c );
break;
case Abs:
SATURN_PEEKOP_ADR(v);
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], v );
break;
case BranchReturn:
SATURN_PEEKOP_DIS8(v);
if (v==0) {
stream << mnemonics[level->mnemonic+1][mnemonics_bank];
} else {
c=(pc+pos-2+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], c);
}
break;
case ABranchReturn:
SATURN_PEEKOP_DIS8(v);
if (v==0) {
util::stream_format(stream, mnemonics[level->mnemonic+1][mnemonics_bank], A);
} else {
c=(pc+pos-2+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], A, c);
}
break;
case xBranchReturn:
SATURN_PEEKOP_DIS8(v);
if (v==0) {
util::stream_format(stream, mnemonics[level->mnemonic+1][mnemonics_bank], field_2_string(adr));
} else {
c=(pc+pos-2+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], field_2_string(adr), c);
}
break;
case TestBranchRet:
i=opcodes.r8(pos++);
SATURN_PEEKOP_DIS8(v);
if (v==0) {
util::stream_format(stream, mnemonics[level->mnemonic+1][mnemonics_bank], i);
} else {
c=(pc+pos-2+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], i, c);
}
break;
case ImmBranch:
i=opcodes.r8(pos++);
SATURN_PEEKOP_DIS8(v);
c=(pc+pos-2+v)&0xfffff;
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], i, c);
break;
case FieldP:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], P );
break;
case FieldWP:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], WP );
break;
case FieldXS:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], XS );
break;
case FieldX:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], X );
break;
case FieldS:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], S );
break;
case FieldM:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], M );
break;
case FieldB:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], B );
break;
case FieldA:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], A );
break;
case FieldW:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], W );
break;
case AdrA:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], adr_a[opcodes.r8(pos++) & 0x7] );
break;
case AdrAF:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], adr_af[opcodes.r8(pos++) & 0xf] );
break;
case AdrB:
util::stream_format(stream, mnemonics[level->mnemonic][mnemonics_bank], adr_b[opcodes.r8(pos++) & 0x7] );
break;
}
break;
}
level = opcs[level->sel];
}
return pos - pc;
}
