Stub out MMU functions, opcodes; const fixes.

src/config.c

@@ -364,7 +364,7 @@ void config_destroy(Config *config)
 /*
     DEBUG FUNCTION: Print out all config arguments to stdout.
 */
-void config_dump_args(Config* config)
+void config_dump_args(const Config* config)
 {
     DEBUG("Dumping arguments:")
     DEBUG("- fullscreen:  %s", config->fullscreen ? "true" : "false")

src/config.h

@@ -38,5 +38,5 @@ int config_create(Config**, int, char*[]);
 void config_destroy(Config*);
 
 #ifdef DEBUG_MODE
-void config_dump_args(Config*);
+void config_dump_args(const Config*);
 #endif

src/gamegear.c

@@ -21,7 +21,8 @@ GameGear* gamegear_create()
     if (!gg)
         OUT_OF_MEMORY()
 
-    // mmu_init(&gg->mmu, ...);
+    if (!mmu_init(&gg->mmu))
+        OUT_OF_MEMORY()
     z80_init(&gg->cpu, &gg->mmu);
     gg->powered = false;
     gg->exc_buffer[0] = '\0';
@@ -35,22 +36,23 @@ GameGear* gamegear_create()
 */
 void gamegear_destroy(GameGear *gg)
 {
-    // mmu_free(&gg->mmu);
+    mmu_free(&gg->mmu);
     free(gg);
 }
 
 /*
     Load a ROM image into the GameGear object.
 
-    Does *not* steal a reference to the ROM object. Calling this function while
-    the GameGear is powered on has no effect.
+    Does *not* steal a reference to the ROM object, so it must be kept alive
+    until another ROM is loaded or the GameGear is destroyed. Calling this
+    function while the GameGear is powered on has no effect.
 */
-void gamegear_load(GameGear *gg, ROM *rom)
+void gamegear_load(GameGear *gg, const ROM *rom)
 {
     if (gg->powered)
         return;
 
-    // mmu_hard_map(&gg->mmu, rom->data, ..., ...);
+    mmu_load_rom(&gg->mmu, rom->data, rom->size);
 }
 
 /*
@@ -68,7 +70,7 @@ void gamegear_power(GameGear *gg, bool state)
         return;
 
     if (state) {
-        // mmu_power(&gg->mmu);
+        mmu_power(&gg->mmu);
         z80_power(&gg->cpu);
         gg->last_tick = get_time_ns();
     } else {

src/gamegear.h

@@ -26,7 +26,7 @@ typedef struct {
 
 GameGear* gamegear_create();
 void gamegear_destroy(GameGear*);
-void gamegear_load(GameGear*, ROM*);
+void gamegear_load(GameGear*, const ROM*);
 void gamegear_power(GameGear*, bool);
 bool gamegear_simulate(GameGear*);
 const char* gamegear_get_exception(GameGear*);

src/mmu.c

@@ -5,8 +5,55 @@
 
 /*
     Initialize a MMU object.
+
+    Return true if initialization was successful, or false if the required
+    amount of memory could not be allocated.
+*/
+bool mmu_init(MMU *mmu)
+{
+    // TODO
+    return true;
+}
+
+/*
+    Free memory previously allocated by the MMU.
+*/
+void mmu_free(MMU *mmu)
+{
+    // TODO
+}
+
+/*
+    Load a block ROM into the MMU.
+
+    size should be a power of two.
+*/
+void mmu_load_rom(MMU *mmu, const uint8_t *data, size_t size)
+{
+    // TODO
+}
+
+/*
+    Power on the MMU, setting initial memory values.
+*/
+void mmu_power(MMU *mmu)
+{
+    // TODO
+}
+
+/*
+    Read a byte of memory.
+*/
+uint8_t mmu_read_byte(MMU *mmu, uint16_t addr)
+{
+    // TODO
+    return 0x00;
+}
+
+/*
+    ...
 */
-// void mmu_init(MMU *mmu, ...)
-// {
-//     //
-// }
+void mmu_write_byte(MMU *mmu, uint16_t addr, uint8_t value)
+{
+    // TODO
+}

src/mmu.h

@@ -3,7 +3,9 @@
 
 #pragma once
 
-// #include <>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
 
 /* Structs */
 
@@ -13,4 +15,9 @@ typedef struct {
 
 /* Functions */
 
-// void mmu_init(MMU*, ...);
+bool mmu_init(MMU*);
+void mmu_free(MMU*);
+void mmu_load_rom(MMU*, const uint8_t*, size_t);
+void mmu_power(MMU*);
+uint8_t mmu_read_byte(MMU*, uint16_t);
+void mmu_write_byte(MMU*, uint16_t, uint8_t);

src/z80.c

@@ -63,7 +63,7 @@ void z80_power(Z80 *z80)
 /*
     Return whether a particular flag is set in the F register.
 */
-static inline bool get_flag(Z80 *z80, uint8_t flag)
+static inline bool get_flag(const Z80 *z80, uint8_t flag)
 {
     return z80->regfile.f & (1 << flag);
 }
@@ -71,7 +71,7 @@ static inline bool get_flag(Z80 *z80, uint8_t flag)
 /*
     Return whether a particular flag is set in the F' register.
 */
-static inline bool get_shadow_flag(Z80 *z80, uint8_t flag)
+static inline bool get_shadow_flag(const Z80 *z80, uint8_t flag)
 {
     return z80->regfile.f_ & (1 << flag);
 }
@@ -79,7 +79,7 @@ static inline bool get_shadow_flag(Z80 *z80, uint8_t flag)
 /*
     Return the CPU's current interrupt mode.
 */
-static inline uint8_t get_interrupt_mode(Z80 *z80)
+static inline uint8_t get_interrupt_mode(const Z80 *z80)
 {
     if (!z80->regfile.im_a)
         return 0;
@@ -101,8 +101,7 @@ bool z80_do_cycles(Z80 *z80, double cycles)
 {
     cycles -= z80->pending_cycles;
     while (cycles > 0 && !z80->except) {
-        // uint8_t opcode = mmu_read_byte(&z80->mmu, z80->regfile.pc);
-        uint8_t opcode = 0x00;
+        uint8_t opcode = mmu_read_byte(z80->mmu, z80->regfile.pc);
         cycles -= (*instruction_lookup_table[opcode])(z80, opcode) - 2;
     }
 
@@ -114,9 +113,9 @@ bool z80_do_cycles(Z80 *z80, double cycles)
 /*
     DEBUG FUNCTION: Print out all register values to stdout.
 */
-void z80_dump_registers(Z80 *z80)
+void z80_dump_registers(const Z80 *z80)
 {
-    Z80RegFile *regfile = &z80->regfile;
+    const Z80RegFile *regfile = &z80->regfile;
     DEBUG("Dumping Z80 register values:")
 
     DEBUG("- AF:   0x%02X%02X (C: %u, N: %u, P/V: %u, H: %u, Z: %u, S: %u)",

src/z80.h

@@ -37,5 +37,5 @@ void z80_power(Z80*);
 bool z80_do_cycles(Z80*, double);
 
 #ifdef DEBUG_MODE
-void z80_dump_registers(Z80*);
+void z80_dump_registers(const Z80*);
 #endif

src/z80_instructions.inc

@@ -20,7 +20,7 @@ static uint8_t z80_inst_nop(Z80 *z80, uint8_t opcode)
 /*
     Unimplemented opcode handler.
 */
-static uint8_t z80_inst_ERR(Z80 *z80, uint8_t opcode)
+static uint8_t z80_inst_unimplemented(Z80 *z80, uint8_t opcode)
 {
     z80->except = true;
     z80->exc_code = Z80_EXC_UNIMPLEMENTED_OPCODE;
@@ -29,6 +29,260 @@ static uint8_t z80_inst_ERR(Z80 *z80, uint8_t opcode)
 }
 
 static uint8_t (*instruction_lookup_table[256])(Z80*, uint8_t) = {
-    z80_inst_nop,
-    z80_inst_ERR
+    /* 0x00 */ z80_inst_nop,
+    /* 0x01 */ z80_inst_unimplemented,
+    /* 0x02 */ z80_inst_unimplemented,
+    /* 0x03 */ z80_inst_unimplemented,
+    /* 0x04 */ z80_inst_unimplemented,
+    /* 0x05 */ z80_inst_unimplemented,
+    /* 0x06 */ z80_inst_unimplemented,
+    /* 0x07 */ z80_inst_unimplemented,
+    /* 0x08 */ z80_inst_unimplemented,
+    /* 0x09 */ z80_inst_unimplemented,
+    /* 0x0A */ z80_inst_unimplemented,
+    /* 0x0B */ z80_inst_unimplemented,
+    /* 0x0C */ z80_inst_unimplemented,
+    /* 0x0D */ z80_inst_unimplemented,
+    /* 0x0E */ z80_inst_unimplemented,
+    /* 0x0F */ z80_inst_unimplemented,
+    /* 0x10 */ z80_inst_unimplemented,
+    /* 0x11 */ z80_inst_unimplemented,
+    /* 0x12 */ z80_inst_unimplemented,
+    /* 0x13 */ z80_inst_unimplemented,
+    /* 0x14 */ z80_inst_unimplemented,
+    /* 0x15 */ z80_inst_unimplemented,
+    /* 0x16 */ z80_inst_unimplemented,
+    /* 0x17 */ z80_inst_unimplemented,
+    /* 0x18 */ z80_inst_unimplemented,
+    /* 0x19 */ z80_inst_unimplemented,
+    /* 0x1A */ z80_inst_unimplemented,
+    /* 0x1B */ z80_inst_unimplemented,
+    /* 0x1C */ z80_inst_unimplemented,
+    /* 0x1D */ z80_inst_unimplemented,
+    /* 0x1E */ z80_inst_unimplemented,
+    /* 0x1F */ z80_inst_unimplemented,
+    /* 0x20 */ z80_inst_unimplemented,
+    /* 0x21 */ z80_inst_unimplemented,
+    /* 0x22 */ z80_inst_unimplemented,
+    /* 0x23 */ z80_inst_unimplemented,
+    /* 0x24 */ z80_inst_unimplemented,
+    /* 0x25 */ z80_inst_unimplemented,
+    /* 0x26 */ z80_inst_unimplemented,
+    /* 0x27 */ z80_inst_unimplemented,
+    /* 0x28 */ z80_inst_unimplemented,
+    /* 0x29 */ z80_inst_unimplemented,
+    /* 0x2A */ z80_inst_unimplemented,
+    /* 0x2B */ z80_inst_unimplemented,
+    /* 0x2C */ z80_inst_unimplemented,
+    /* 0x2D */ z80_inst_unimplemented,
+    /* 0x2E */ z80_inst_unimplemented,
+    /* 0x2F */ z80_inst_unimplemented,
+    /* 0x30 */ z80_inst_unimplemented,
+    /* 0x31 */ z80_inst_unimplemented,
+    /* 0x32 */ z80_inst_unimplemented,
+    /* 0x33 */ z80_inst_unimplemented,
+    /* 0x34 */ z80_inst_unimplemented,
+    /* 0x35 */ z80_inst_unimplemented,
+    /* 0x36 */ z80_inst_unimplemented,
+    /* 0x37 */ z80_inst_unimplemented,
+    /* 0x38 */ z80_inst_unimplemented,
+    /* 0x39 */ z80_inst_unimplemented,
+    /* 0x3A */ z80_inst_unimplemented,
+    /* 0x3B */ z80_inst_unimplemented,
+    /* 0x3C */ z80_inst_unimplemented,
+    /* 0x3D */ z80_inst_unimplemented,
+    /* 0x3E */ z80_inst_unimplemented,
+    /* 0x3F */ z80_inst_unimplemented,
+    /* 0x40 */ z80_inst_unimplemented,
+    /* 0x41 */ z80_inst_unimplemented,
+    /* 0x42 */ z80_inst_unimplemented,
+    /* 0x43 */ z80_inst_unimplemented,
+    /* 0x44 */ z80_inst_unimplemented,
+    /* 0x45 */ z80_inst_unimplemented,
+    /* 0x46 */ z80_inst_unimplemented,
+    /* 0x47 */ z80_inst_unimplemented,
+    /* 0x48 */ z80_inst_unimplemented,
+    /* 0x49 */ z80_inst_unimplemented,
+    /* 0x4A */ z80_inst_unimplemented,
+    /* 0x4B */ z80_inst_unimplemented,
+    /* 0x4C */ z80_inst_unimplemented,
+    /* 0x4D */ z80_inst_unimplemented,
+    /* 0x4E */ z80_inst_unimplemented,
+    /* 0x4F */ z80_inst_unimplemented,
+    /* 0x50 */ z80_inst_unimplemented,
+    /* 0x51 */ z80_inst_unimplemented,
+    /* 0x52 */ z80_inst_unimplemented,
+    /* 0x53 */ z80_inst_unimplemented,
+    /* 0x54 */ z80_inst_unimplemented,
+    /* 0x55 */ z80_inst_unimplemented,
+    /* 0x56 */ z80_inst_unimplemented,
+    /* 0x57 */ z80_inst_unimplemented,
+    /* 0x58 */ z80_inst_unimplemented,
+    /* 0x59 */ z80_inst_unimplemented,
+    /* 0x5A */ z80_inst_unimplemented,
+    /* 0x5B */ z80_inst_unimplemented,
+    /* 0x5C */ z80_inst_unimplemented,
+    /* 0x5D */ z80_inst_unimplemented,
+    /* 0x5E */ z80_inst_unimplemented,
+    /* 0x5F */ z80_inst_unimplemented,
+    /* 0x60 */ z80_inst_unimplemented,
+    /* 0x61 */ z80_inst_unimplemented,
+    /* 0x62 */ z80_inst_unimplemented,
+    /* 0x63 */ z80_inst_unimplemented,
+    /* 0x64 */ z80_inst_unimplemented,
+    /* 0x65 */ z80_inst_unimplemented,
+    /* 0x66 */ z80_inst_unimplemented,
+    /* 0x67 */ z80_inst_unimplemented,
+    /* 0x68 */ z80_inst_unimplemented,
+    /* 0x69 */ z80_inst_unimplemented,
+    /* 0x6A */ z80_inst_unimplemented,
+    /* 0x6B */ z80_inst_unimplemented,
+    /* 0x6C */ z80_inst_unimplemented,
+    /* 0x6D */ z80_inst_unimplemented,
+    /* 0x6E */ z80_inst_unimplemented,
+    /* 0x6F */ z80_inst_unimplemented,
+    /* 0x70 */ z80_inst_unimplemented,
+    /* 0x71 */ z80_inst_unimplemented,
+    /* 0x72 */ z80_inst_unimplemented,
+    /* 0x73 */ z80_inst_unimplemented,
+    /* 0x74 */ z80_inst_unimplemented,
+    /* 0x75 */ z80_inst_unimplemented,
+    /* 0x76 */ z80_inst_unimplemented,
+    /* 0x77 */ z80_inst_unimplemented,
+    /* 0x78 */ z80_inst_unimplemented,
+    /* 0x79 */ z80_inst_unimplemented,
+    /* 0x7A */ z80_inst_unimplemented,
+    /* 0x7B */ z80_inst_unimplemented,
+    /* 0x7C */ z80_inst_unimplemented,
+    /* 0x7D */ z80_inst_unimplemented,
+    /* 0x7E */ z80_inst_unimplemented,
+    /* 0x7F */ z80_inst_unimplemented,
+    /* 0x80 */ z80_inst_unimplemented,
+    /* 0x81 */ z80_inst_unimplemented,
+    /* 0x82 */ z80_inst_unimplemented,
+    /* 0x83 */ z80_inst_unimplemented,
+    /* 0x84 */ z80_inst_unimplemented,
+    /* 0x85 */ z80_inst_unimplemented,
+    /* 0x86 */ z80_inst_unimplemented,
+    /* 0x87 */ z80_inst_unimplemented,
+    /* 0x88 */ z80_inst_unimplemented,
+    /* 0x89 */ z80_inst_unimplemented,
+    /* 0x8A */ z80_inst_unimplemented,
+    /* 0x8B */ z80_inst_unimplemented,
+    /* 0x8C */ z80_inst_unimplemented,
+    /* 0x8D */ z80_inst_unimplemented,
+    /* 0x8E */ z80_inst_unimplemented,
+    /* 0x8F */ z80_inst_unimplemented,
+    /* 0x90 */ z80_inst_unimplemented,
+    /* 0x91 */ z80_inst_unimplemented,
+    /* 0x92 */ z80_inst_unimplemented,
+    /* 0x93 */ z80_inst_unimplemented,
+    /* 0x94 */ z80_inst_unimplemented,
+    /* 0x95 */ z80_inst_unimplemented,
+    /* 0x96 */ z80_inst_unimplemented,
+    /* 0x97 */ z80_inst_unimplemented,
+    /* 0x98 */ z80_inst_unimplemented,
+    /* 0x99 */ z80_inst_unimplemented,
+    /* 0x9A */ z80_inst_unimplemented,
+    /* 0x9B */ z80_inst_unimplemented,
+    /* 0x9C */ z80_inst_unimplemented,
+    /* 0x9D */ z80_inst_unimplemented,
+    /* 0x9E */ z80_inst_unimplemented,
+    /* 0x9F */ z80_inst_unimplemented,
+    /* 0xA0 */ z80_inst_unimplemented,
+    /* 0xA1 */ z80_inst_unimplemented,
+    /* 0xA2 */ z80_inst_unimplemented,
+    /* 0xA3 */ z80_inst_unimplemented,
+    /* 0xA4 */ z80_inst_unimplemented,
+    /* 0xA5 */ z80_inst_unimplemented,
+    /* 0xA6 */ z80_inst_unimplemented,
+    /* 0xA7 */ z80_inst_unimplemented,
+    /* 0xA8 */ z80_inst_unimplemented,
+    /* 0xA9 */ z80_inst_unimplemented,
+    /* 0xAA */ z80_inst_unimplemented,
+    /* 0xAB */ z80_inst_unimplemented,
+    /* 0xAC */ z80_inst_unimplemented,
+    /* 0xAD */ z80_inst_unimplemented,
+    /* 0xAE */ z80_inst_unimplemented,
+    /* 0xAF */ z80_inst_unimplemented,
+    /* 0xB0 */ z80_inst_unimplemented,
+    /* 0xB1 */ z80_inst_unimplemented,
+    /* 0xB2 */ z80_inst_unimplemented,
+    /* 0xB3 */ z80_inst_unimplemented,
+    /* 0xB4 */ z80_inst_unimplemented,
+    /* 0xB5 */ z80_inst_unimplemented,
+    /* 0xB6 */ z80_inst_unimplemented,
+    /* 0xB7 */ z80_inst_unimplemented,
+    /* 0xB8 */ z80_inst_unimplemented,
+    /* 0xB9 */ z80_inst_unimplemented,
+    /* 0xBA */ z80_inst_unimplemented,
+    /* 0xBB */ z80_inst_unimplemented,
+    /* 0xBC */ z80_inst_unimplemented,
+    /* 0xBD */ z80_inst_unimplemented,
+    /* 0xBE */ z80_inst_unimplemented,
+    /* 0xBF */ z80_inst_unimplemented,
+    /* 0xC0 */ z80_inst_unimplemented,
+    /* 0xC1 */ z80_inst_unimplemented,
+    /* 0xC2 */ z80_inst_unimplemented,
+    /* 0xC3 */ z80_inst_unimplemented,
+    /* 0xC4 */ z80_inst_unimplemented,
+    /* 0xC5 */ z80_inst_unimplemented,
+    /* 0xC6 */ z80_inst_unimplemented,
+    /* 0xC7 */ z80_inst_unimplemented,
+    /* 0xC8 */ z80_inst_unimplemented,
+    /* 0xC9 */ z80_inst_unimplemented,
+    /* 0xCA */ z80_inst_unimplemented,
+    /* 0xCB */ z80_inst_unimplemented,
+    /* 0xCC */ z80_inst_unimplemented,
+    /* 0xCD */ z80_inst_unimplemented,
+    /* 0xCE */ z80_inst_unimplemented,
+    /* 0xCF */ z80_inst_unimplemented,
+    /* 0xD0 */ z80_inst_unimplemented,
+    /* 0xD1 */ z80_inst_unimplemented,
+    /* 0xD2 */ z80_inst_unimplemented,
+    /* 0xD3 */ z80_inst_unimplemented,
+    /* 0xD4 */ z80_inst_unimplemented,
+    /* 0xD5 */ z80_inst_unimplemented,
+    /* 0xD6 */ z80_inst_unimplemented,
+    /* 0xD7 */ z80_inst_unimplemented,
+    /* 0xD8 */ z80_inst_unimplemented,
+    /* 0xD9 */ z80_inst_unimplemented,
+    /* 0xDA */ z80_inst_unimplemented,
+    /* 0xDB */ z80_inst_unimplemented,
+    /* 0xDC */ z80_inst_unimplemented,
+    /* 0xDD */ z80_inst_unimplemented,
+    /* 0xDE */ z80_inst_unimplemented,
+    /* 0xDF */ z80_inst_unimplemented,
+    /* 0xE0 */ z80_inst_unimplemented,
+    /* 0xE1 */ z80_inst_unimplemented,
+    /* 0xE2 */ z80_inst_unimplemented,
+    /* 0xE3 */ z80_inst_unimplemented,
+    /* 0xE4 */ z80_inst_unimplemented,
+    /* 0xE5 */ z80_inst_unimplemented,
+    /* 0xE6 */ z80_inst_unimplemented,
+    /* 0xE7 */ z80_inst_unimplemented,
+    /* 0xE8 */ z80_inst_unimplemented,
+    /* 0xE9 */ z80_inst_unimplemented,
+    /* 0xEA */ z80_inst_unimplemented,
+    /* 0xEB */ z80_inst_unimplemented,
+    /* 0xEC */ z80_inst_unimplemented,
+    /* 0xED */ z80_inst_unimplemented,
+    /* 0xEE */ z80_inst_unimplemented,
+    /* 0xEF */ z80_inst_unimplemented,
+    /* 0xF0 */ z80_inst_unimplemented,
+    /* 0xF1 */ z80_inst_unimplemented,
+    /* 0xF2 */ z80_inst_unimplemented,
+    /* 0xF3 */ z80_inst_unimplemented,
+    /* 0xF4 */ z80_inst_unimplemented,
+    /* 0xF5 */ z80_inst_unimplemented,
+    /* 0xF6 */ z80_inst_unimplemented,
+    /* 0xF7 */ z80_inst_unimplemented,
+    /* 0xF8 */ z80_inst_unimplemented,
+    /* 0xF9 */ z80_inst_unimplemented,
+    /* 0xFA */ z80_inst_unimplemented,
+    /* 0xFB */ z80_inst_unimplemented,
+    /* 0xFC */ z80_inst_unimplemented,
+    /* 0xFD */ z80_inst_unimplemented,
+    /* 0xFE */ z80_inst_unimplemented,
+    /* 0xFF */ z80_inst_unimplemented
 };