test_cpu_simple - Add DAA example as a test

tests/test_cpu_simple.cpp

@@ -217,3 +217,35 @@ TEST_CASE("RST op leads to correct call")
 
   CHECK(cpu.state.PC == expected_pc);
 }
+
+TEST_CASE("DAA")
+{
+  u8 test_ram[] = {
+    0x80, // ADD A,B
+    0x27, // DAA
+    0x90, // SUB A,B
+    0x27, // DAA
+  };
+
+  RAM r(test_ram, 0x4, true);
+  Cpu cpu(&r);
+
+  cpu.state.A = 0x45;
+  cpu.state.B = 0x38;
+
+  cpu.step();
+
+  CHECK(cpu.state.A == 0x7D);
+
+  cpu.step();
+
+  CHECK(cpu.state.A == 0x83);
+
+  cpu.step();
+
+  CHECK(cpu.state.A == 0x4B);
+
+  cpu.step();
+
+  CHECK(cpu.state.A == 0x45);
+}