From 3f317e4c9f2831607eab520f97b356829b06d0d7 Mon Sep 17 00:00:00 2001
From: Forest Belton <forest@homolo.gy>
Date: Fri, 23 Jul 2021 00:56:24 -0400
Subject: [PATCH] Finish CPU implementation

---
 gbso/cpu.py  | 31 +++++++++++++++++++++----------
 gbso/regs.py | 13 +++++++++++++
 2 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/gbso/cpu.py b/gbso/cpu.py
index ab071f5..d5e0948 100644
--- a/gbso/cpu.py
+++ b/gbso/cpu.py
@@ -1,35 +1,46 @@
-from gbso.regs import R8, R16
+from collections import defaultdict
+from typing import Dict
+
+from gbso.regs import R16_HI, R16_LO, R8, R16
 
 
 class CPU:
     carry: int
+    cycles: int
+    reg8: Dict[R8, int]
+    memory: bytearray
 
     def __init__(self) -> None:
         self.carry = 0
+        self.cycles = 0
+        self.reg8 = defaultdict(lambda: 0)
+        self.memory = bytearray(0xFFFF + 1)
 
     def get_reg8(self, r: R8) -> int:
-        pass
+        return self.reg8[r]
 
     def get_reg16(self, rr: R16) -> int:
-        pass
+        return (self.reg8[R16_HI[rr]] << 8) | self.reg8[R16_LO[rr]]
 
     def set_reg8(self, r: R8, n: int) -> None:
-        pass
+        self.reg8[r] = n & 0xFF
 
-    def set_reg16(self, r: R16, nn: int) -> None:
-        pass
+    def set_reg16(self, rr: R16, nn: int) -> None:
+        self.reg8[R16_HI[rr]] = (nn >> 8) & 0xFF
+        self.reg8[R16_LO[rr]] = nn & 0xFF
 
     def get_mem8(self, nn: int) -> int:
-        pass
+        return self.memory[nn & 0xFFFF]
 
     def get_mem16(self, nn: int) -> int:
-        pass
+        return (self.memory[(nn + 1) & 0xFF] << 8) | self.memory[nn & 0xFFFF]
 
     def set_mem8(self, nn: int, n: int) -> None:
-        pass
+        self.memory[nn & 0xFFFF] = n & 0xFF
 
     def set_mem16(self, nn: int, nn1: int) -> None:
-        pass
+        self.memory[nn & 0xFFFF] = nn1 & 0xFF
+        self.memory[(nn + 1) & 0xFFFF] = (nn1 >> 8) & 0xFF
 
     def deref_hl(self) -> int:
         return self.get_mem8(self.get_reg16(R16.HL))
diff --git a/gbso/regs.py b/gbso/regs.py
index 2537b79..c518c0f 100644
--- a/gbso/regs.py
+++ b/gbso/regs.py
@@ -17,3 +17,16 @@ class R16(Enum):
     DE = "DE"
     HL = "HL"
     SP = "SP"
+
+
+R16_HI = {
+    R16.BC: R8.B,
+    R16.DE: R8.D,
+    R16.HL: R8.H,
+}
+
+R16_LO = {
+    R16.BC: R8.C,
+    R16.DE: R8.E,
+    R16.HL: R8.L,
+}