static void saturn_instruction(saturn_state *cpustate)
{
int reg, adr;
switch(READ_OP(cpustate)) {
case 0:
switch(READ_OP(cpustate)) {
case 0: saturn_return_xm_set(cpustate);break;
case 1: saturn_return(cpustate, 1);break;
case 2: saturn_return_carry_set(cpustate);break;
case 3: saturn_return_carry_clear(cpustate);break;
case 4: saturn_sethex(cpustate);break;
case 5: saturn_setdec(cpustate);break;
case 6: saturn_push_c(cpustate);break;
case 7: saturn_pop_c(cpustate);break;
case 8: saturn_clear_st(cpustate);break;
case 9: saturn_st_to_c(cpustate);break;
case 0xa: saturn_c_to_st(cpustate);break;
case 0xb: saturn_exchange_c_st(cpustate);break;
case 0xc: saturn_inc_p(cpustate);break;
case 0xd: saturn_dec_p(cpustate);break;
case 0xe: saturn_instruction_0e(cpustate);break;
case 0xf: saturn_return_interrupt(cpustate);break;
}
break;
case 1:
saturn_instruction_1(cpustate);
break;
case 2:
saturn_load_p(cpustate);
break;
case 3:
saturn_load_reg(cpustate, C);
break; // lc
case 4:
adr=READ_OP_DIS8(cpustate);
if (adr==0) {
saturn_return(cpustate, cpustate->carry);
}
else {
saturn_jump(cpustate, (cpustate->pc+adr-2)&0xfffff, cpustate->carry);
}
break;
case 5:
adr=READ_OP_DIS8(cpustate);
if (adr==0) {
saturn_return(cpustate, !cpustate->carry);
}
else {
saturn_jump(cpustate, (cpustate->pc+adr-2)&0xfffff,!cpustate->carry);
}
break;
case 6:
adr=READ_OP_DIS12(cpustate);
saturn_jump(cpustate, (cpustate->pc+adr-3)&0xfffff,1); break;
case 7:
adr=READ_OP_DIS12(cpustate);
saturn_call(cpustate, (adr+cpustate->pc)&0xfffff); break;
case 8:
saturn_instruction_8(cpustate);
break;
case 9:
saturn_instruction_9(cpustate);
break;
case 0xa:
saturn_instruction_a(cpustate);
break;
case 0xb:
saturn_instruction_b(cpustate);
break;
case 0xc:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(cpustate, add_left[reg], BEGIN_A, COUNT_A, add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_add(cpustate, A+(reg&3), BEGIN_A, COUNT_A, A+(reg&3));
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(cpustate, A+(reg&3), BEGIN_A, COUNT_A);
break;
}
break;
case 0xd:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
saturn_clear(cpustate, A+reg, BEGIN_A, COUNT_A);
break; // a=0 a
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(cpustate, reg_right[reg&7], BEGIN_A, COUNT_A, reg_left[reg&7]);
break; // a=b a
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(cpustate, reg_left[reg&3], BEGIN_A, COUNT_A, reg_right[reg&3]);
break; // abex a
}
break;
case 0xe:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_sub(cpustate, sub_left[reg], BEGIN_A, COUNT_A, sub_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_increment(cpustate, A+(reg&3), BEGIN_A, COUNT_A);
break; // a=a+1 a
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_sub2(cpustate, sub_left[reg], BEGIN_A, COUNT_A, sub_right[reg]);
break;
}
break;
case 0xf:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
saturn_shift_nibble_left(cpustate, A+reg,BEGIN_A, COUNT_A);
break; // asl a
case 4: case 5: case 6: case 7:
saturn_shift_nibble_right(cpustate, A+(reg&3),BEGIN_A, COUNT_A);
break; // asr a
case 8: case 9: case 0xa: case 0xb:
saturn_negate(cpustate, A+(reg&3),BEGIN_A, COUNT_A);
break; // A=-A a
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_invert(cpustate, A+(reg&3),BEGIN_A, COUNT_A);
break; // A=-A-1 a
}
break;
}
}
static void saturn_instruction_81a(saturn_state *cpustate)
{
int reg, adr,op;
switch(adr=READ_OP(cpustate)) {
case 0:
switch(op=READ_OP(cpustate)) {
case 0:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, R0+reg,cpustate->p,1,A);
break; //r0=a p
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, R0+(reg&7),cpustate->p,1,C);
break; //r0=c p
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 1:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, A,cpustate->p,1,R0+reg);
break; //a=r0 p
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, C,cpustate->p,1,R0+(reg&7));
break; //c=r0 p
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 2:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(cpustate, A, cpustate->p,1,R0+reg);
break; // ar0ex p
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(cpustate, C, cpustate->p,1,R0+(reg&7));
break; // cr0ex p
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
default:
saturn_invalid5( cpustate, 8, 1, 0xa, adr, op );
break;
}
break;
case 1:
switch(op=READ_OP(cpustate)) {
case 0:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, R0+reg,0,cpustate->p+1,A);
break; //r0=a wp
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, R0+(reg&7),0,cpustate->p+1,C);
break; //r0=c wp
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 1:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, A,0,cpustate->p+1,R0+reg);
break; //a=r0 wp
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, C,0,cpustate->p+1,R0+(reg&7));
break; //c=r0 wp
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 2:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(cpustate, A, 0, cpustate->p+1, R0+reg);
break; // ar0ex wp
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(cpustate, C, 0, cpustate->p+1, R0+(reg&7));
break; // cr0ex wp
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
default:
saturn_invalid5( cpustate, 8, 1, 0xa, adr, op );
break;
}
break;
case 2: case 3: case 4: case 5: case 6: case 7: case 0xf:
switch(op=READ_OP(cpustate)) {
case 0:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, R0+reg,adr_af_begin[adr],adr_af_count[adr],A);
break; //r0=a xs
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, R0+(reg&7),adr_af_begin[adr], adr_af_count[adr],C);
break; //r0=c xs
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 1:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, A,adr_af_begin[adr],adr_af_count[adr],R0+reg);
break; //a=r0 xs
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, C,adr_af_begin[adr],adr_af_count[adr],R0+(reg&7));
break; //c=r0 xs
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
case 2:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(cpustate, A, adr_af_begin[adr], adr_af_count[adr], R0+reg);
break; // ar0ex xs
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(cpustate, C, adr_af_begin[adr], adr_af_count[adr], R0+(reg&7));
break; // cr0ex xs
default:
saturn_invalid6( cpustate, 8, 1, 0xa, adr, op, reg);
break;
}
break;
default:
saturn_invalid5( cpustate, 8, 1, 0xa, adr, op );
break;
}
break;
default:
saturn_invalid4( cpustate, 8, 1, 0xa, adr );
break;
}
}
static void saturn_instruction_a(saturn_state *cpustate)
{
int reg, adr;
switch(adr=READ_OP(cpustate)) {
case 0:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(cpustate, add_left[reg], cpustate->p, 1, add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_add(cpustate, A+(reg&3), cpustate->p, 1, A+(reg&3));
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(cpustate, A+(reg&3), cpustate->p, 1);
break;
}
break;
case 1:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(cpustate, add_left[reg], 0, cpustate->p+1, add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_add(cpustate, A+(reg&3), 0, cpustate->p+1, A+(reg&3));
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(cpustate, A+(reg&3), 0, cpustate->p+1);
break;
}
break;
case 2: case 3: case 4: case 5: case 6: case 7:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(cpustate, add_left[reg], adr_a_begin[adr], adr_a_count[adr], add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_add(cpustate, A+(reg&3), adr_a_begin[adr], adr_a_count[adr], A+(reg&3));
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(cpustate, A+(reg&3), adr_a_begin[adr], adr_a_count[adr]);
break;
}
break;
case 8:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
saturn_clear(cpustate, A+reg, cpustate->p,1);
break; // a=0 p
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(cpustate, reg_right[reg&7], cpustate->p,1,reg_left[reg&7]);
break; // a=b p
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(cpustate, reg_left[reg&3], cpustate->p,1,reg_right[reg&3]);
break; // abex p
}
break;
case 9:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
saturn_clear(cpustate, A+reg,0,cpustate->p+1);
break; // a=0 wp
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(cpustate, reg_right[reg&7], 0, cpustate->p+1, reg_left[reg&7]);
break; // a=b wp
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(cpustate, reg_left[reg&3], 0, cpustate->p+1, reg_right[reg&3]);
break; // abex wp
}
break;
case 0xa: case 0xb: case 0xc: case 0xd: case 0xe: case 0xf:
switch(reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3:
saturn_clear(cpustate, A+reg, adr_b_begin[adr], adr_b_count[adr]);
break; // a=0 xs
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(cpustate, reg_right[reg&7], adr_b_begin[adr], adr_b_count[adr], reg_left[reg&7]);
break; // a=b xs
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(cpustate, reg_left[reg&3], adr_b_begin[adr], adr_b_count[adr], reg_right[reg&3]);
break; // abex xs
}
break;
}
}
static void saturn_instruction_1(saturn_state *cpustate)
{
int reg, adr, oper;
switch (adr=READ_OP(cpustate)) {
case 0:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, R0+reg, BEGIN_W, COUNT_W, A);
break; // r0=a w
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, R0+(reg&7), BEGIN_W, COUNT_W, C);
break; // r0=c w
default:
saturn_invalid3( cpustate, 1, adr, reg );
break;
}
break;
case 1:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(cpustate, A, BEGIN_W, COUNT_W, R0+reg);
break; // a=r0 w
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(cpustate, C, BEGIN_W, COUNT_W, R0+(reg&7));
break; // c=r0 w
default:
saturn_invalid3( cpustate, 1, adr, reg );
break;
}
break;
case 2:
switch (reg=READ_OP(cpustate)) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(cpustate, A, BEGIN_W, COUNT_W, R0+reg);
break; // ar0ex w
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(cpustate, C, BEGIN_W, COUNT_W, R0+(reg&7));
break; // cr0ex w
default:
saturn_invalid3( cpustate, 2, adr, reg );
break;
}
break;
case 3:
switch (READ_OP(cpustate)) {
case 0: saturn_reg_to_adr(cpustate, A,0);break;
case 1: saturn_reg_to_adr(cpustate, A,1);break;
case 2: saturn_exchange_adr_reg(cpustate, 0,A);break;
case 3: saturn_exchange_adr_reg(cpustate, 1,A);break;
case 4: saturn_reg_to_adr(cpustate, C,0);break;
case 5: saturn_reg_to_adr(cpustate, C,1);break;
case 6: saturn_exchange_adr_reg(cpustate, 0,C);break;
case 7: saturn_exchange_adr_reg(cpustate, 1,C);break;
case 8: saturn_reg_to_adr_word(cpustate, A,0);break;
case 9: saturn_reg_to_adr_word(cpustate, A,1);break;
case 0xa: saturn_exchange_adr_reg_word(cpustate, 0,A);break;
case 0xb: saturn_exchange_adr_reg_word(cpustate, 1,A);break;
case 0xc: saturn_reg_to_adr_word(cpustate, C,0);break;
case 0xd: saturn_reg_to_adr_word(cpustate, C,1);break;
case 0xe: saturn_exchange_adr_reg_word(cpustate, 0,C);break;
case 0xf: saturn_exchange_adr_reg_word(cpustate, 1,C);break;
}
break;
case 4:
switch (READ_OP(cpustate)) {
case 0: saturn_store_nibbles(cpustate, A, BEGIN_A, COUNT_A, 0); break;
case 1: saturn_store_nibbles(cpustate, A, BEGIN_A, COUNT_A, 1); break;
case 2: saturn_load_nibbles(cpustate, A, BEGIN_A, COUNT_A, 0); break;
case 3: saturn_load_nibbles(cpustate, A, BEGIN_A, COUNT_A, 1); break;
case 4: saturn_store_nibbles(cpustate, C, BEGIN_A, COUNT_A, 0); break;
case 5: saturn_store_nibbles(cpustate, C, BEGIN_A, COUNT_A, 1); break;
case 6: saturn_load_nibbles(cpustate, C, BEGIN_A, COUNT_A, 0); break;
case 7: saturn_load_nibbles(cpustate, C, BEGIN_A, COUNT_A, 1); break;
case 8: saturn_store_nibbles(cpustate, A, BEGIN_B, COUNT_B, 0); break;
case 9: saturn_store_nibbles(cpustate, A, BEGIN_B, COUNT_B, 1); break;
case 0xa: saturn_load_nibbles(cpustate, A, BEGIN_B, COUNT_B, 0); break;
case 0xb: saturn_load_nibbles(cpustate, A, BEGIN_B, COUNT_B, 1); break;
case 0xc: saturn_store_nibbles(cpustate, C, BEGIN_B, COUNT_B, 0); break;
case 0xd: saturn_store_nibbles(cpustate, C, BEGIN_B, COUNT_B, 1); break;
case 0xe: saturn_load_nibbles(cpustate, C, BEGIN_B, COUNT_B, 0); break;
case 0xf: saturn_load_nibbles(cpustate, C, BEGIN_B, COUNT_B, 1); break;
}
break;
case 5:
switch (oper=READ_OP(cpustate)) {
case 0: case 1: case 4: case 5:
switch (adr=READ_OP(cpustate)) {
case 0:
saturn_store_nibbles(cpustate, oper&4?C:A,cpustate->p,1,oper&1);
break;
case 1:
saturn_store_nibbles(cpustate, oper&4?C:A,0,cpustate->p+1,oper&1);
break;
case 2: case 3: case 4: case 5: case 6: case 7:
saturn_store_nibbles(cpustate, oper&4?C:A,adr_a_begin[adr],adr_a_count[adr],oper&1);
break;
default:
saturn_invalid4( cpustate, 1, 5, oper, adr );
break;
}
break;
case 2: case 3: case 6: case 7:
switch (adr=READ_OP(cpustate)) {
case 0:
saturn_load_nibbles(cpustate, oper&4?C:A,cpustate->p,1,oper&1);
break;
case 1:
saturn_load_nibbles(cpustate, oper&4?C:A,0,cpustate->p+1,oper&1);
break;
case 2: case 3: case 4: case 5: case 6: case 7:
saturn_load_nibbles(cpustate, oper&4?C:A,adr_a_begin[adr],adr_a_count[adr],oper&1);
break;
default:
saturn_invalid4( cpustate, 1, 5, oper, adr );
break;
}
break;
case 8: saturn_store_nibbles(cpustate, A, 0, READ_OP(cpustate)+1, 0); break;
case 9: saturn_store_nibbles(cpustate, A, 0, READ_OP(cpustate)+1, 1); break;
case 0xa: saturn_load_nibbles(cpustate, A, 0, READ_OP(cpustate)+1, 0); break;
case 0xb: saturn_load_nibbles(cpustate, A, 0, READ_OP(cpustate)+1, 1); break;
case 0xc: saturn_store_nibbles(cpustate, C, 0, READ_OP(cpustate)+1, 0); break;
case 0xd: saturn_store_nibbles(cpustate, C, 0, READ_OP(cpustate)+1, 1); break;
case 0xe: saturn_load_nibbles(cpustate, C, 0, READ_OP(cpustate)+1, 0); break;
case 0xf: saturn_load_nibbles(cpustate, C, 0, READ_OP(cpustate)+1, 1); break;
}
break;
case 6: saturn_add_adr(cpustate, 0);break;
case 7: saturn_add_adr(cpustate, 1);break;
case 8: saturn_sub_adr(cpustate, 0);break;
case 9: saturn_load_adr(cpustate, 0,2);break;
case 0xa: saturn_load_adr(cpustate, 0,4);break;
case 0xb: saturn_load_adr(cpustate, 0,5);break;
case 0xc: saturn_sub_adr(cpustate, 1);break;
case 0xd: saturn_load_adr(cpustate, 1,2);break;
case 0xe: saturn_load_adr(cpustate, 1,4);break;
case 0xf: saturn_load_adr(cpustate, 1,5);break;
}
}
static void saturn_instruction(void)
{
int reg, adr;
switch(READ_OP()) {
case 0:
switch(READ_OP()) {
case 0: saturn_return_xm_set();break;
case 1: saturn_return(1);break;
case 2: saturn_return_carry_set();break;
case 3: saturn_return_carry_clear();break;
case 4: saturn_sethex();break;
case 5: saturn_setdec();break;
case 6: saturn_push_c();break;
case 7: saturn_pop_c();break;
case 8: saturn_clear_st();break;
case 9: saturn_st_to_c();break;
case 0xa: saturn_c_to_st();break;
case 0xb: saturn_exchange_c_st();break;
case 0xc:
saturn_inc_p();
break;
case 0xd:
saturn_dec_p();
break;
case 0xf: saturn_return_interrupt();break;
case 0xe:
saturn_instruction_0e();
break;
}
break;
case 1:
saturn_instruction_1();
break;
case 2:
saturn_load_p();
break;
case 3: saturn_load_reg(C);break; /* lc */
case 4:
adr=READ_OP_DIS8();
if (adr==0) {
saturn_return(saturn.carry);
} else {
saturn_jump((saturn.pc+adr-2)&0xfffff, saturn.carry);
}
break;
case 5:
adr=READ_OP_DIS8();
if (adr==0) {
saturn_return(!saturn.carry);
} else {
saturn_jump((saturn.pc+adr-2)&0xfffff,!saturn.carry);
}
break;
case 6:
adr=READ_OP_DIS12();
saturn_jump((saturn.pc+adr-3)&0xfffff,1); break;
case 7:
adr=READ_OP_DIS12();
saturn_call((adr+saturn.pc)&0xfffff); break;
case 8:
saturn_instruction_8();
break;
case 9:
saturn_instruction_9();
break;
case 0xa:
saturn_instruction_a();
break;
case 0xb:
saturn_instruction_b();
break;
case 0xc:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(add_left[reg], BEGIN_A, COUNT_A, add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_shift_left(A+(reg&3), BEGIN_A, COUNT_A);
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(A+(reg&3), BEGIN_A, COUNT_A);
break;
}
break;
case 0xd:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
saturn_clear(A+reg, BEGIN_A, COUNT_A);
break; /* a=0 a */
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(reg_right[reg&7], BEGIN_A, COUNT_A, reg_left[reg&7]); /*correct */
break; /* a=b a */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(reg_left[reg&3], BEGIN_A, COUNT_A, reg_right[reg&3]);
break; /* abex a */
}
break;
case 0xe:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_sub(sub_left[reg], BEGIN_A, COUNT_A, S64_READ_A(sub_right[reg]));
break;
case 4: case 5: case 6: case 7:
saturn_increment(A+(reg&3), BEGIN_A, COUNT_A);
break; /* a=a+1 a */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_sub2(sub_left[reg], BEGIN_A, COUNT_A, S64_READ_A(sub_right[reg]));
break;
}
break;
case 0xf:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
saturn_shift_nibble_left(A+reg,BEGIN_A, COUNT_A);
break; /* asl a */
case 4: case 5: case 6: case 7:
saturn_shift_nibble_right(A+(reg&3),BEGIN_A, COUNT_A);
break; /* asr a */
case 8: case 9: case 0xa: case 0xb:
saturn_invert(A+(reg&3),BEGIN_A, COUNT_A);
break; /* A=-A a */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_negate(A+(reg&3),BEGIN_A, COUNT_A);
break; /* A=-A-1 a */
}
break;
}
}
static void saturn_instruction_1(void)
{
int reg, adr, oper;
switch (adr=READ_OP()) {
case 0:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(R0+reg, BEGIN_W, COUNT_W, A);
break; /* r0=a w */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(R0+(reg&7), BEGIN_W, COUNT_W, C);
break; /* r0=c w */
}
break;
case 1:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(A, BEGIN_W, COUNT_W, R0+reg);
break; /* a=r0 w */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(C, BEGIN_W, COUNT_W, R0+(reg&7));
break; /* c=r0 w */
}
break;
case 2:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(A, BEGIN_W, COUNT_W, R0+reg);
break; /* ar0ex w */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(C, BEGIN_W, COUNT_W, R0+(reg&7));
break; /* cr0ex w */
}
break;
case 3:
switch (READ_OP()) {
case 0: saturn_reg_to_adr(A,0);break;
case 1: saturn_reg_to_adr(A,1);break;
case 2: saturn_exchange_adr_reg(0,A);break;
case 3: saturn_exchange_adr_reg(1,A);break;
case 4: saturn_reg_to_adr(C,0);break;
case 5: saturn_reg_to_adr(C,1);break;
case 6: saturn_exchange_adr_reg(0,C);break;
case 7: saturn_exchange_adr_reg(1,C);break;
case 8: saturn_reg_to_adr_word(A,0);break;
case 9: saturn_reg_to_adr_word(A,1);break;
case 0xa: saturn_exchange_adr_reg_word(0,A);break;
case 0xb: saturn_exchange_adr_reg_word(1,A);break;
case 0xc: saturn_reg_to_adr_word(C,0);break;
case 0xd: saturn_reg_to_adr_word(C,1);break;
case 0xe: saturn_exchange_adr_reg_word(0,C);break;
case 0xf: saturn_exchange_adr_reg_word(1,C);break;
}
break;
case 4:
switch (READ_OP()) {
case 0: saturn_store_nibbles(A, BEGIN_A, COUNT_A, 0); break;
case 1: saturn_store_nibbles(A, BEGIN_A, COUNT_A, 1); break;
case 2: saturn_load_nibbles(A, BEGIN_A, COUNT_A, 0); break;
case 3: saturn_load_nibbles(A, BEGIN_A, COUNT_A, 1); break;
case 4: saturn_store_nibbles(C, BEGIN_A, COUNT_A, 0); break;
case 5: saturn_store_nibbles(C, BEGIN_A, COUNT_A, 1); break;
case 6: saturn_load_nibbles(C, BEGIN_A, COUNT_A, 0); break;
case 7: saturn_load_nibbles(C, BEGIN_A, COUNT_A, 1); break;
case 8: saturn_store_nibbles(A, BEGIN_B, COUNT_B, 0); break;
case 9: saturn_store_nibbles(A, BEGIN_B, COUNT_B, 1); break;
case 0xa: saturn_load_nibbles(A, BEGIN_B, COUNT_B, 0); break;
case 0xb: saturn_load_nibbles(A, BEGIN_B, COUNT_B, 1); break;
case 0xc: saturn_store_nibbles(C, BEGIN_B, COUNT_B, 0); break;
case 0xd: saturn_store_nibbles(C, BEGIN_B, COUNT_B, 1); break;
case 0xe: saturn_load_nibbles(C, BEGIN_B, COUNT_B, 0); break;
case 0xf: saturn_load_nibbles(C, BEGIN_B, COUNT_B, 1); break;
}
break;
case 5:
switch (oper=READ_OP()) {
case 0: case 1: case 4: case 5:
switch (adr=READ_OP()) {
case 0:
saturn_store_nibbles(oper&4?C:A,saturn.p,1,oper&1);
break;
case 1:
saturn_store_nibbles(oper&4?C:A,0,saturn.p+1,oper&1);
break;
case 2: case 3: case 4: case 5: case 6: case 7:
saturn_store_nibbles(oper&4?C:A,adr_a_begin[adr],adr_a_count[adr],oper&1);
break;
}
break;
case 2: case 3: case 6: case 7:
switch (adr=READ_OP()) {
case 0:
saturn_load_nibbles(oper&4?C:A,saturn.p,1,oper&1);
break;
case 1:
saturn_load_nibbles(oper&4?C:A,0,saturn.p+1,oper&1);
break;
case 2: case 3: case 4: case 5: case 6: case 7:
saturn_load_nibbles(oper&4?C:A,adr_a_begin[adr],adr_a_count[adr],oper&1);
break;
}
break;
case 8: saturn_store_nibbles(A, 0, READ_OP()+1, 0); break;
case 9: saturn_store_nibbles(A, 0, READ_OP()+1, 1); break;
case 0xa: saturn_load_nibbles(A, 0, READ_OP()+1, 0); break;
case 0xb: saturn_load_nibbles(A, 0, READ_OP()+1, 1); break;
case 0xc: saturn_store_nibbles(C, 0, READ_OP()+1, 0); break;
case 0xd: saturn_store_nibbles(C, 0, READ_OP()+1, 1); break;
case 0xe: saturn_load_nibbles(C, 0, READ_OP()+1, 0); break;
case 0xf: saturn_load_nibbles(C, 0, READ_OP()+1, 1); break;
}
break;
case 9: saturn_load_adr(0,2);break;
case 0xa: saturn_load_adr(0,4);break;
case 0xb: saturn_load_adr(0,5);break;
case 0xd: saturn_load_adr(1,2);break;
case 0xe: saturn_load_adr(1,4);break;
case 0xf: saturn_load_adr(1,5);break;
case 6: saturn_add_adr(0);break;
case 7: saturn_add_adr(1);break;
case 8: saturn_sub_adr(0);break;
case 0xc: saturn_sub_adr(1);break;
}
}
static void saturn_instruction_a(void)
{
int reg, adr;
switch(adr=READ_OP()) {
case 0:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(add_left[reg], saturn.p, 1, add_right[reg]);
break;
break;
case 4: case 5: case 6: case 7:
saturn_shift_left(A+(reg&3), saturn.p, 1);
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(A+(reg&3), saturn.p, 1);
break;
}
break;
case 1:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(add_left[reg], 1, saturn.p+1, add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_shift_left(A+(reg&3), 1, saturn.p+1);
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(A+(reg&3), 1, saturn.p+1);
break;
}
break;
case 2: case 3: case 4: case 5: case 6: case 7:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3:
case 8: case 9: case 0xa: case 0xb:
saturn_add(add_left[reg], adr_a_begin[adr], adr_a_count[adr], add_right[reg]);
break;
case 4: case 5: case 6: case 7:
saturn_shift_left(A+(reg&3), adr_a_begin[adr], adr_a_count[adr]);
break;
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_decrement(A+(reg&3), adr_a_begin[adr], adr_a_count[adr]);
break;
}
break;
case 8:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
saturn_clear(A+reg, saturn.p,1);
break; /* a=0 p */
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(reg_right[reg&7], saturn.p,1,reg_left[reg&7]); /*!correct */
break; /* a=b p */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(reg_left[reg&3], saturn.p,1,reg_right[reg&3]);
break; /* abex p */
}
break;
case 9:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
saturn_clear(A+reg,0,saturn.p+1);
break; /* a=0 wp */
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(reg_right[reg&7], 0, saturn.p+1, reg_left[reg&7]); /*!correct */
break; /* a=b wp */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(reg_left[reg&3], 0, saturn.p+1, reg_right[reg&3]);
break; /* abex wp */
}
break;
case 0xa: case 0xb: case 0xc: case 0xd: case 0xe: case 0xf:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3:
saturn_clear(A+reg, adr_b_begin[adr], adr_b_count[adr]);
break; /* a=0 xs */
case 4: case 5: case 6: case 7:
case 8: case 9: case 0xa: case 0xb:
saturn_copy(reg_right[reg&7], adr_b_begin[adr], adr_b_count[adr],
reg_left[reg&7]); /*correct */
break; /* a=b xs */
case 0xc: case 0xd: case 0xe: case 0xf:
saturn_exchange(reg_left[reg&3], adr_b_begin[adr], adr_b_count[adr],
reg_right[reg&3]);
break; /* abex xs */
}
break;
}
}
static void saturn_instruction_81a(void)
{
int reg, adr;
switch(adr=READ_OP()) {
case 0:
switch(READ_OP()) {
case 0:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(R0+reg,saturn.p,1,A);
break; /*r0=a p */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(R0+(reg&7),saturn.p,1,C);
break; /*r0=c p */
}
break;
case 1:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(A,saturn.p,1,R0+reg);
break; /*a=r0 p */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(C,saturn.p,1,R0+(reg&7));
break; /*c=r0 p */
}
break;
case 2:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(A, saturn.p,1,R0+reg);
break; /* ar0ex p */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(C, saturn.p,1,R0+(reg&7));
break; /* cr0ex p */
}
break;
}
break;
case 1:
switch(READ_OP()) {
case 0:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(R0+reg,0,saturn.p+1,A);
break; /*r0=a wp */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(R0+(reg&7),0,saturn.p+1,C);
break; /*r0=c wp */
}
break;
case 1:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(A,0,saturn.p+1,R0+reg);
break; /*a=r0 wp */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(C,0,saturn.p+1,R0+(reg&7));
break; /*c=r0 wp */
}
break;
case 2:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(A, 0, saturn.p+1, R0+reg);
break; /* ar0ex wp */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(C, 0, saturn.p+1, R0+(reg&7));
break; /* cr0ex wp */
}
break;
}
break;
case 2: case 3: case 4: case 5: case 6: case 7: case 0xf:
switch(READ_OP()) {
case 0:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(R0+reg,adr_af_begin[adr],adr_af_count[adr],A);
break; /*r0=a xs */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(R0+(reg&7),adr_af_begin[adr], adr_af_count[adr],C);
break; /*r0=c xs */
}
break;
case 1:
switch(reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_copy(A,adr_af_begin[adr],adr_af_count[adr],R0+reg);
break; /*a=r0 xs */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_copy(C,adr_af_begin[adr],adr_af_count[adr],R0+(reg&7));
break; /*c=r0 xs */
}
break;
case 2:
switch (reg=READ_OP()) {
case 0: case 1: case 2: case 3: case 4:
saturn_exchange(A, adr_af_begin[adr], adr_af_count[adr], R0+reg);
break; /* ar0ex xs */
case 8: case 9: case 0xa: case 0xb: case 0xc:
saturn_exchange(C, adr_af_begin[adr], adr_af_count[adr], R0+(reg&7));
break; /* cr0ex xs */
}
break;
}
break;
}
}
