6502: Lua bindings for testing

1 files changed, 34 insertions, 5 deletions

diff --git a/6502/include/lcq/6502.h b/6502/include/lcq/6502.h
index cb3b1fa..4d20e26 100644
--- a/6502/include/lcq/6502.h
+++ b/6502/include/lcq/6502.h
@@ -13,10 +13,14 @@ typedef enum {
     L6502_FLAG_NEGATIVE = 1 << 7,
 } l6502_flag;
 
-typedef struct {
-    u16 pc;
-    u8 sp, a, x, y, flags;
-} l6502_regs;
+typedef enum {
+    L6502_REG_SP = 0,
+    L6502_REG_A,
+    L6502_REG_X,
+    L6502_REG_Y,
+    L6502_REG_FLAGS,
+    L6502_REG__MARKER,
+} l6502_reg;
 
 typedef u8 (*l6502_mem_read_handler)(void *data, u16 addr);
 typedef void (*l6502_mem_write_handler)(void *data, u16 addr, u8 val);
@@ -28,10 +32,35 @@ typedef struct {
 void l6502_mem_basic_new(l6502_mem *m);
 
 typedef struct {
-    l6502_regs regs;
+    u16 pc;
+    l6502_reg regs[L6502_REG__MARKER];
     l6502_mem mem;
 } l6502_emu;
 
+static inline u8 l6502_flag_get(l6502_emu *e, l6502_flag f) { return (e->regs[L6502_REG_FLAGS] & (u8) f) != 0; }
+static inline void l6502_flag_set(l6502_emu *e, l6502_flag f, u8 v) {
+    if (v) e->regs[L6502_REG_FLAGS] |= (u8) f;
+    else e->regs[L6502_REG_FLAGS] &= ~((u8) f);
+}
+static inline u8 l6502_read(l6502_emu *e, u16 addr) { return e->mem.rh(e->mem.data, addr); }
+static inline void l6502_write(l6502_emu *e, u16 addr, u8 val) { e->mem.wh(e->mem.data, addr, val); }
+static inline u16 l6502_read_addr(l6502_emu *e, u16 addr) {
+    u8 alo = l6502_read(e, addr);
+    u8 ahi = l6502_read(e, addr + 1);
+    return ahi << 8 | alo;
+}
+static inline u8 l6502_pop(l6502_emu *e) { return l6502_read(e, 0x0100 + (u16) ++e->regs[L6502_REG_SP]); }
+static inline void l6502_push(l6502_emu *e, u8 val) { l6502_write(e, 0x0100 + (u16) e->regs[L6502_REG_SP]--, val); }
+static inline u16 l6502_pop_addr(l6502_emu *e) {
+    u8 ahi = l6502_pop(e);
+    u8 alo = l6502_pop(e);
+    return ahi << 8 | alo;
+}
+static inline void l6502_push_addr(l6502_emu *e, u16 addr) {
+    l6502_push(e, (u8) (addr & 0xff));
+    l6502_push(e, (u8) (addr >> 8));
+}
+
 void l6502_emulate(l6502_emu *e);
 
 #endif