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crater
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mmu_write_double, stack_push; LD (HL), n; JR; CALL

master
Ben Kurtovic 8 years ago
parent
c2a52194a8
commit
8de5117a49
5 changed files with 99 additions and 27 deletions
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  1. +10
    -0
      src/mmu.c
  2. +1
    -0
      src/mmu.h
  3. +9
    -0
      src/z80.c
  4. +64
    -12
      src/z80_ops.inc.c
  5. +15
    -15
      src/z80_tables.inc.c

+ 10
- 0
src/mmu.c View File

@@ -181,3 +181,13 @@ bool mmu_write_byte(MMU *mmu, uint16_t addr, uint8_t value)
return true; return true;
} }
} }

/*
Write two bytes of memory to the given address.
*/
bool mmu_write_double(MMU *mmu, uint16_t addr, uint16_t value)
{
bool b1 = mmu_write_byte(mmu, addr, value & 0xFF);
bool b2 = mmu_write_byte(mmu, addr + 1, value >> 8);
return b1 && b2;
}

+ 1
- 0
src/mmu.h View File

@@ -30,3 +30,4 @@ uint8_t mmu_read_byte(const MMU*, uint16_t);
uint16_t mmu_read_double(const MMU*, uint16_t); uint16_t mmu_read_double(const MMU*, uint16_t);
uint32_t mmu_read_quad(const MMU*, uint16_t); uint32_t mmu_read_quad(const MMU*, uint16_t);
bool mmu_write_byte(MMU*, uint16_t, uint8_t); bool mmu_write_byte(MMU*, uint16_t, uint8_t);
bool mmu_write_double(MMU*, uint16_t, uint16_t);

+ 9
- 0
src/z80.c View File

@@ -161,6 +161,15 @@ static inline void update_flags(Z80 *z80, bool c, bool n, bool pv, bool f3,
} }


/* /*
Push a two-byte value onto the stack.
*/
static inline void stack_push(Z80 *z80, uint16_t value)
{
z80->regfile.sp -= 2;
mmu_write_double(z80->mmu, z80->regfile.sp, value);
}

/*
Read and return a byte from the given port. Read and return a byte from the given port.
*/ */
static uint8_t read_port(Z80 *z80, uint8_t port) static uint8_t read_port(Z80 *z80, uint8_t port)


+ 64
- 12
src/z80_ops.inc.c View File

@@ -99,9 +99,18 @@ static uint8_t z80_inst_ld_r_hl(Z80 *z80, uint8_t opcode)
// static uint8_t z80_inst_ld_iy_r(Z80 *z80, uint8_t opcode) // static uint8_t z80_inst_ld_iy_r(Z80 *z80, uint8_t opcode)


/* /*
LD (HL), n
LD (HL), n (0x36):
Load n (8-bit immediate) into the memory address pointed to by HL.
*/ */
// static uint8_t z80_inst_ld_hl_n(Z80 *z80, uint8_t opcode)
static uint8_t z80_inst_ld_hl_n(Z80 *z80, uint8_t opcode)
{
(void) opcode;
uint16_t addr = get_pair(z80, REG_HL);
uint8_t byte = mmu_read_byte(z80->mmu, ++z80->regfile.pc);
mmu_write_byte(z80->mmu, addr, byte);
z80->regfile.pc++;
return 10;
}


/* /*
LD (IX+d), n LD (IX+d), n
@@ -564,19 +573,38 @@ static uint8_t z80_inst_jp_cc_nn(Z80 *z80, uint8_t opcode)
if (extract_cond(z80, opcode)) if (extract_cond(z80, opcode))
z80->regfile.pc = mmu_read_double(z80->mmu, ++z80->regfile.pc); z80->regfile.pc = mmu_read_double(z80->mmu, ++z80->regfile.pc);
else else
z80->regfile.pc += 2;
z80->regfile.pc += 3;
return 10; return 10;
} }


// JR e

// JR C, e

// JR NC, e
/*
JR e (0x18):
Relative jump e (signed 8-bit immediate) bytes.
*/
static uint8_t z80_inst_jr_e(Z80 *z80, uint8_t opcode)
{
(void) opcode;
int8_t jump = mmu_read_byte(z80->mmu, ++z80->regfile.pc);
z80->regfile.pc += jump + 2;
return 12;
}


// JR Z, e


// JR NZ, e
/*
JR cc, e (0x20, 0x28, 0x30, 0x38):
Relative jump e (signed 8-bit immediate) bytes if cc (condition) is true.
*/
static uint8_t z80_inst_jr_cc_e(Z80 *z80, uint8_t opcode)
{
if (extract_cond(z80, opcode - 0x20)) {
int8_t jump = mmu_read_byte(z80->mmu, ++z80->regfile.pc);
z80->regfile.pc += jump + 2;
return 12;
} else {
z80->regfile.pc += 2;
return 7;
}
}


// JP (HL) // JP (HL)


@@ -586,9 +614,33 @@ static uint8_t z80_inst_jp_cc_nn(Z80 *z80, uint8_t opcode)


// DJNZ, e // DJNZ, e


// CALL nn
/*
CALL nn (0xCD):
Push PC+3 onto the stack and jump to nn (16-bit immediate).
*/
static uint8_t z80_inst_call_nn(Z80 *z80, uint8_t opcode)
{
(void) opcode;
stack_push(z80, z80->regfile.pc + 3);
z80->regfile.pc = mmu_read_double(z80->mmu, ++z80->regfile.pc);
return 17;
}


// CALL cc, nn
/*
CALL cc, nn (0xC4, 0xCC, 0xD4, 0xDC, 0xE4, 0xEC, 0xF4, 0xFC):
Push PC+3 onto the stack and jump to nn (16-bit immediate) if cc is true.
*/
static uint8_t z80_inst_call_cc_nn(Z80 *z80, uint8_t opcode)
{
if (extract_cond(z80, opcode)) {
stack_push(z80, z80->regfile.pc + 3);
z80->regfile.pc = mmu_read_double(z80->mmu, ++z80->regfile.pc);
return 17;
} else {
z80->regfile.pc += 3;
return 10;
}
}


// RET // RET




+ 15
- 15
src/z80_tables.inc.c View File

@@ -26,7 +26,7 @@ static DispatchTable instruction_table = {
[0x15] = z80_inst_unimplemented, // TODO [0x15] = z80_inst_unimplemented, // TODO
[0x16] = z80_inst_ld_r_n, [0x16] = z80_inst_ld_r_n,
[0x17] = z80_inst_unimplemented, // TODO [0x17] = z80_inst_unimplemented, // TODO
[0x18] = z80_inst_unimplemented, // TODO
[0x18] = z80_inst_jr_e,
[0x19] = z80_inst_unimplemented, // TODO [0x19] = z80_inst_unimplemented, // TODO
[0x1A] = z80_inst_unimplemented, // TODO [0x1A] = z80_inst_unimplemented, // TODO
[0x1B] = z80_inst_unimplemented, // TODO [0x1B] = z80_inst_unimplemented, // TODO
@@ -34,7 +34,7 @@ static DispatchTable instruction_table = {
[0x1D] = z80_inst_unimplemented, // TODO [0x1D] = z80_inst_unimplemented, // TODO
[0x1E] = z80_inst_ld_r_n, [0x1E] = z80_inst_ld_r_n,
[0x1F] = z80_inst_unimplemented, // TODO [0x1F] = z80_inst_unimplemented, // TODO
[0x20] = z80_inst_unimplemented, // TODO
[0x20] = z80_inst_jr_cc_e,
[0x21] = z80_inst_ld_dd_nn, [0x21] = z80_inst_ld_dd_nn,
[0x22] = z80_inst_unimplemented, // TODO [0x22] = z80_inst_unimplemented, // TODO
[0x23] = z80_inst_inc_ss, [0x23] = z80_inst_inc_ss,
@@ -42,7 +42,7 @@ static DispatchTable instruction_table = {
[0x25] = z80_inst_unimplemented, // TODO [0x25] = z80_inst_unimplemented, // TODO
[0x26] = z80_inst_ld_r_n, [0x26] = z80_inst_ld_r_n,
[0x27] = z80_inst_unimplemented, // TODO [0x27] = z80_inst_unimplemented, // TODO
[0x28] = z80_inst_unimplemented, // TODO
[0x28] = z80_inst_jr_cc_e,
[0x29] = z80_inst_unimplemented, // TODO [0x29] = z80_inst_unimplemented, // TODO
[0x2A] = z80_inst_unimplemented, // TODO [0x2A] = z80_inst_unimplemented, // TODO
[0x2B] = z80_inst_unimplemented, // TODO [0x2B] = z80_inst_unimplemented, // TODO
@@ -50,15 +50,15 @@ static DispatchTable instruction_table = {
[0x2D] = z80_inst_unimplemented, // TODO [0x2D] = z80_inst_unimplemented, // TODO
[0x2E] = z80_inst_ld_r_n, [0x2E] = z80_inst_ld_r_n,
[0x2F] = z80_inst_unimplemented, // TODO [0x2F] = z80_inst_unimplemented, // TODO
[0x30] = z80_inst_unimplemented, // TODO
[0x30] = z80_inst_jr_cc_e,
[0x31] = z80_inst_ld_dd_nn, [0x31] = z80_inst_ld_dd_nn,
[0x32] = z80_inst_ld_nn_a, [0x32] = z80_inst_ld_nn_a,
[0x33] = z80_inst_inc_ss, [0x33] = z80_inst_inc_ss,
[0x34] = z80_inst_unimplemented, // TODO [0x34] = z80_inst_unimplemented, // TODO
[0x35] = z80_inst_unimplemented, // TODO [0x35] = z80_inst_unimplemented, // TODO
[0x36] = z80_inst_unimplemented, // TODO
[0x36] = z80_inst_ld_hl_n,
[0x37] = z80_inst_unimplemented, // TODO [0x37] = z80_inst_unimplemented, // TODO
[0x38] = z80_inst_unimplemented, // TODO
[0x38] = z80_inst_jr_cc_e,
[0x39] = z80_inst_unimplemented, // TODO [0x39] = z80_inst_unimplemented, // TODO
[0x3A] = z80_inst_unimplemented, // TODO [0x3A] = z80_inst_unimplemented, // TODO
[0x3B] = z80_inst_unimplemented, // TODO [0x3B] = z80_inst_unimplemented, // TODO
@@ -198,7 +198,7 @@ static DispatchTable instruction_table = {
[0xC1] = z80_inst_unimplemented, // TODO [0xC1] = z80_inst_unimplemented, // TODO
[0xC2] = z80_inst_jp_cc_nn, [0xC2] = z80_inst_jp_cc_nn,
[0xC3] = z80_inst_jp_nn, [0xC3] = z80_inst_jp_nn,
[0xC4] = z80_inst_unimplemented, // TODO
[0xC4] = z80_inst_call_cc_nn,
[0xC5] = z80_inst_unimplemented, // TODO [0xC5] = z80_inst_unimplemented, // TODO
[0xC6] = z80_inst_unimplemented, // TODO [0xC6] = z80_inst_unimplemented, // TODO
[0xC7] = z80_inst_unimplemented, // TODO [0xC7] = z80_inst_unimplemented, // TODO
@@ -206,15 +206,15 @@ static DispatchTable instruction_table = {
[0xC9] = z80_inst_unimplemented, // TODO [0xC9] = z80_inst_unimplemented, // TODO
[0xCA] = z80_inst_jp_cc_nn, [0xCA] = z80_inst_jp_cc_nn,
[0xCB] = z80_prefix_bits, [0xCB] = z80_prefix_bits,
[0xCC] = z80_inst_unimplemented, // TODO
[0xCD] = z80_inst_unimplemented, // TODO
[0xCC] = z80_inst_call_cc_nn,
[0xCD] = z80_inst_call_nn,
[0xCE] = z80_inst_unimplemented, // TODO [0xCE] = z80_inst_unimplemented, // TODO
[0xCF] = z80_inst_unimplemented, // TODO [0xCF] = z80_inst_unimplemented, // TODO
[0xD0] = z80_inst_unimplemented, // TODO [0xD0] = z80_inst_unimplemented, // TODO
[0xD1] = z80_inst_unimplemented, // TODO [0xD1] = z80_inst_unimplemented, // TODO
[0xD2] = z80_inst_jp_cc_nn, [0xD2] = z80_inst_jp_cc_nn,
[0xD3] = z80_inst_out_n_a, [0xD3] = z80_inst_out_n_a,
[0xD4] = z80_inst_unimplemented, // TODO
[0xD4] = z80_inst_call_cc_nn,
[0xD5] = z80_inst_unimplemented, // TODO [0xD5] = z80_inst_unimplemented, // TODO
[0xD6] = z80_inst_unimplemented, // TODO [0xD6] = z80_inst_unimplemented, // TODO
[0xD7] = z80_inst_unimplemented, // TODO [0xD7] = z80_inst_unimplemented, // TODO
@@ -222,7 +222,7 @@ static DispatchTable instruction_table = {
[0xD9] = z80_inst_exx, [0xD9] = z80_inst_exx,
[0xDA] = z80_inst_jp_cc_nn, [0xDA] = z80_inst_jp_cc_nn,
[0xDB] = z80_inst_in_a_n, [0xDB] = z80_inst_in_a_n,
[0xDC] = z80_inst_unimplemented, // TODO
[0xDC] = z80_inst_call_cc_nn,
[0xDD] = z80_prefix_index, [0xDD] = z80_prefix_index,
[0xDE] = z80_inst_unimplemented, // TODO [0xDE] = z80_inst_unimplemented, // TODO
[0xDF] = z80_inst_unimplemented, // TODO [0xDF] = z80_inst_unimplemented, // TODO
@@ -230,7 +230,7 @@ static DispatchTable instruction_table = {
[0xE1] = z80_inst_unimplemented, // TODO [0xE1] = z80_inst_unimplemented, // TODO
[0xE2] = z80_inst_jp_cc_nn, [0xE2] = z80_inst_jp_cc_nn,
[0xE3] = z80_inst_unimplemented, // TODO [0xE3] = z80_inst_unimplemented, // TODO
[0xE4] = z80_inst_unimplemented, // TODO
[0xE4] = z80_inst_call_cc_nn,
[0xE5] = z80_inst_unimplemented, // TODO [0xE5] = z80_inst_unimplemented, // TODO
[0xE6] = z80_inst_unimplemented, // TODO [0xE6] = z80_inst_unimplemented, // TODO
[0xE7] = z80_inst_unimplemented, // TODO [0xE7] = z80_inst_unimplemented, // TODO
@@ -238,7 +238,7 @@ static DispatchTable instruction_table = {
[0xE9] = z80_inst_unimplemented, // TODO [0xE9] = z80_inst_unimplemented, // TODO
[0xEA] = z80_inst_jp_cc_nn, [0xEA] = z80_inst_jp_cc_nn,
[0xEB] = z80_inst_unimplemented, // TODO [0xEB] = z80_inst_unimplemented, // TODO
[0xEC] = z80_inst_unimplemented, // TODO
[0xEC] = z80_inst_call_cc_nn,
[0xED] = z80_prefix_extended, [0xED] = z80_prefix_extended,
[0xEE] = z80_inst_unimplemented, // TODO [0xEE] = z80_inst_unimplemented, // TODO
[0xEF] = z80_inst_unimplemented, // TODO [0xEF] = z80_inst_unimplemented, // TODO
@@ -246,7 +246,7 @@ static DispatchTable instruction_table = {
[0xF1] = z80_inst_unimplemented, // TODO [0xF1] = z80_inst_unimplemented, // TODO
[0xF2] = z80_inst_jp_cc_nn, [0xF2] = z80_inst_jp_cc_nn,
[0xF3] = z80_inst_di, [0xF3] = z80_inst_di,
[0xF4] = z80_inst_unimplemented, // TODO
[0xF4] = z80_inst_call_cc_nn,
[0xF5] = z80_inst_unimplemented, // TODO [0xF5] = z80_inst_unimplemented, // TODO
[0xF6] = z80_inst_unimplemented, // TODO [0xF6] = z80_inst_unimplemented, // TODO
[0xF7] = z80_inst_unimplemented, // TODO [0xF7] = z80_inst_unimplemented, // TODO
@@ -254,7 +254,7 @@ static DispatchTable instruction_table = {
[0xF9] = z80_inst_unimplemented, // TODO [0xF9] = z80_inst_unimplemented, // TODO
[0xFA] = z80_inst_jp_cc_nn, [0xFA] = z80_inst_jp_cc_nn,
[0xFB] = z80_inst_ei, [0xFB] = z80_inst_ei,
[0xFC] = z80_inst_unimplemented, // TODO
[0xFC] = z80_inst_call_cc_nn,
[0xFD] = z80_prefix_index, [0xFD] = z80_prefix_index,
[0xFE] = z80_inst_cp_n, [0xFE] = z80_inst_cp_n,
[0xFF] = z80_inst_unimplemented // TODO [0xFF] = z80_inst_unimplemented // TODO


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