started op table

cpu/operations/add.go

@@ -0,0 +1,11 @@
+package operations
+
+import "radu.macocian.me/goboy/memory"
+
+func ADD(r1 *byte, r2 *byte) {
+	*r1 += *r2
+}
+
+func ADDFromMem(r1 *byte, r2 uint) {
+	*r1 += memory.Read8(r2)
+}

cpu/operations/add_test.go

@@ -0,0 +1,33 @@
+package operations
+
+import (
+	"radu.macocian.me/goboy/memory"
+	"testing"
+)
+
+func TestADD(t *testing.T) {
+	r1 := byte(3)
+	r2 := byte(4)
+	ADD(&r1, &r2)
+
+	expected := byte(7)
+	actual := r1
+
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}
+
+func TestADDFromMem(t *testing.T) {
+	r1 := byte(3)
+	addr := uint(1000)
+	memory.Write8(addr, byte(6))
+	ADDFromMem(&r1, addr)
+
+	expected := byte(9)
+	actual := r1
+
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}

cpu/operations/dec.go

@@ -0,0 +1,14 @@
+package operations
+
+func DEC(r1 *byte) {
+	*r1--
+}
+
+func DEC16(r1 *byte, r2 *byte) {
+	if *r2 == 0x00 {
+		*r2 = 0xFF
+		*r1--
+		return
+	}
+	*r2--
+}

cpu/operations/dec_test.go

@@ -0,0 +1,37 @@
+package operations
+
+import "testing"
+
+func TestDEC(t *testing.T) {
+	r1 := byte(3)
+	DEC(&r1)
+
+	expected := byte(2)
+	actual := r1
+
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}
+
+func TestDEC16(t *testing.T) {
+	r1 := byte(0xAB)
+	r2 := byte(0x11)
+	DEC16(&r1, &r2)
+
+	expected := uint16(0xAB10)
+	actual := (uint16(r1) << 8) | uint16(r2)
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+
+	r1 = byte(0x11)
+	r2 = byte(0x00)
+	DEC16(&r1, &r2)
+
+	expected = uint16(0x1000)
+	actual = (uint16(r1) << 8) | uint16(r2)
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}

cpu/operations/inc.go

@@ -0,0 +1,14 @@
+package operations
+
+func INC(r1 *byte) {
+	*r1++
+}
+
+func INC16(r1 *byte, r2 *byte) {
+	if *r2 == 0xFF {
+		*r2 = 0
+		*r1++
+		return
+	}
+	*r2++
+}

cpu/operations/inc_test.go

@@ -0,0 +1,39 @@
+package operations
+
+import (
+	"testing"
+)
+
+func TestINC(t *testing.T) {
+	r1 := byte(3)
+	INC(&r1)
+
+	expected := byte(4)
+	actual := r1
+
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}
+
+func TestINC16(t *testing.T) {
+	r1 := byte(0xAB)
+	r2 := byte(0x11)
+	INC16(&r1, &r2)
+
+	expected := uint16(0xAB12)
+	actual := (uint16(r1) << 8) | uint16(r2)
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+
+	r1 = byte(0x11)
+	r2 = byte(0xFF)
+	INC16(&r1, &r2)
+
+	expected = uint16(0x1200)
+	actual = (uint16(r1) << 8) | uint16(r2)
+	if actual != expected {
+		t.Errorf("actual %x != expected %x", actual, expected)
+	}
+}

cpu/operations/load.go

@@ -0,0 +1,15 @@
+package operations
+
+import "radu.macocian.me/goboy/memory"
+
+func LD(r1 *byte, val byte) {
+	*r1 = val
+}
+
+func LDFromMem(r1 *byte, r2 uint) {
+	*r1 = memory.Read8(r2)
+}
+
+func LDInMemory8(addr uint16, val byte) {
+	memory.Write8(uint(addr), val)
+}