瀏覽代碼

EXX, DI, EI, HALT

master
Ben Kurtovic 8 年之前
父節點
當前提交
560eceeedf
共有 1 個文件被更改,包括 61 次插入8 次删除
  1. +61
    -8
      src/z80_ops.inc.c

+ 61
- 8
src/z80_ops.inc.c 查看文件

@@ -149,7 +149,28 @@ static uint8_t z80_inst_ld_dd_nn(Z80 *z80, uint8_t opcode)

// EX AF, AF′

// EXX
/*
EXX (0xD9):
Exchange the 2-byte registers with their shadows
(BC <=> BC', DE <=> DE', HL <=> HL').
*/
static uint8_t z80_inst_exx(Z80 *z80, uint8_t opcode)
{
(void) opcode;
uint16_t bc = get_pair(z80, REG_BC),
de = get_pair(z80, REG_DE),
hl = get_pair(z80, REG_HL);

set_pair(z80, REG_BC, get_pair(z80, REG_BC_));
set_pair(z80, REG_DE, get_pair(z80, REG_DE_));
set_pair(z80, REG_HL, get_pair(z80, REG_HL_));

set_pair(z80, REG_BC_, bc);
set_pair(z80, REG_DE_, de);
set_pair(z80, REG_HL_, hl);
z80->regfile.pc++;
return 4;
}

// EX (SP), HL

@@ -253,11 +274,43 @@ static uint8_t z80_inst_nop(Z80 *z80, uint8_t opcode)
return 4;
}

// HALT
/*
HALT (0x76):
Suspend CPU operation by repeatedly executing NOPs until an interrupt or
reset.
*/
static uint8_t z80_inst_halt(Z80 *z80, uint8_t opcode)
{
(void) z80;
(void) opcode;
return 4;
}

// DI
/*
DI (0xF3):
Disable maskable interrupts by resetting both flip-flops.
*/
static uint8_t z80_inst_di(Z80 *z80, uint8_t opcode)
{
(void) opcode;
z80->regfile.iff1 = false;
z80->regfile.iff2 = false;
z80->regfile.pc++;
return 4;
}

// EI
/*
EI (0xFB):
Enable maskable interrupts by setting both flip-flops.
*/
static uint8_t z80_inst_ei(Z80 *z80, uint8_t opcode)
{
(void) opcode;
z80->regfile.iff1 = true;
z80->regfile.iff2 = true;
z80->regfile.pc++;
return 4;
}

// IM 0

@@ -534,7 +587,7 @@ static uint8_t (*instruction_lookup_table[256])(Z80*, uint8_t) = {
[0x73] = z80_inst_unimplemented, // TODO
[0x74] = z80_inst_unimplemented, // TODO
[0x75] = z80_inst_unimplemented, // TODO
[0x76] = z80_inst_unimplemented, // TODO
[0x76] = z80_inst_halt,
[0x77] = z80_inst_unimplemented, // TODO
[0x78] = z80_inst_unimplemented, // TODO
[0x79] = z80_inst_unimplemented, // TODO
@@ -633,7 +686,7 @@ static uint8_t (*instruction_lookup_table[256])(Z80*, uint8_t) = {
[0xD6] = z80_inst_unimplemented, // TODO
[0xD7] = z80_inst_unimplemented, // TODO
[0xD8] = z80_inst_unimplemented, // TODO
[0xD9] = z80_inst_unimplemented, // TODO
[0xD9] = z80_inst_exx,
[0xDA] = z80_inst_unimplemented, // TODO
[0xDB] = z80_inst_unimplemented, // TODO
[0xDC] = z80_inst_unimplemented, // TODO
@@ -659,7 +712,7 @@ static uint8_t (*instruction_lookup_table[256])(Z80*, uint8_t) = {
[0xF0] = z80_inst_unimplemented, // TODO
[0xF1] = z80_inst_unimplemented, // TODO
[0xF2] = z80_inst_unimplemented, // TODO
[0xF3] = z80_inst_unimplemented, // TODO
[0xF3] = z80_inst_di,
[0xF4] = z80_inst_unimplemented, // TODO
[0xF5] = z80_inst_unimplemented, // TODO
[0xF6] = z80_inst_unimplemented, // TODO
@@ -667,7 +720,7 @@ static uint8_t (*instruction_lookup_table[256])(Z80*, uint8_t) = {
[0xF8] = z80_inst_unimplemented, // TODO
[0xF9] = z80_inst_unimplemented, // TODO
[0xFA] = z80_inst_unimplemented, // TODO
[0xFB] = z80_inst_unimplemented, // TODO
[0xFB] = z80_inst_ei,
[0xFC] = z80_inst_unimplemented, // TODO
[0xFD] = z80_inst_unimplemented, // TODO
[0xFE] = z80_inst_unimplemented, // TODO


Loading…
取消
儲存