fixed DMG bootrom colour

Author: thelolagemann

internal/gameboy/gameboy.go

@@ -376,9 +376,9 @@ func NewGameBoy(rom []byte, opts ...Opt) *GameBoy {
 	}
 	// try to load cheats using filename of rom
 	g.Bus.Map(g.model)
+	g.Colourise()
 	if !g.dontBoot {
 		g.CPU.Boot(g.model)
-		g.Colourise()
 		g.Bus.Boot()
 
 		// schedule the frame sequencer event for the next 8192 ticks

internal/io/bus.go

@@ -95,7 +95,6 @@ func (b *Bus) Map(m types.Model) {
 
 	// setup CGB only registers
 	if b.isGBC && b.c.IsCGBCartridge() {
-		b.vRAMBankMask = 1
 		b.ReserveAddress(types.KEY0, func(v byte) byte {
 			// KEY0 is only writable when boot ROM is running TODO verify
 			if !b.bootROMDone {
@@ -196,6 +195,7 @@ func (b *Bus) Map(m types.Model) {
 
 	// setup cgb model registers
 	if b.model == types.CGBABC || b.model == types.CGB0 {
+		b.vRAMBankMask = 1
 		b.ReserveAddress(types.VBK, func(v byte) byte {
 			if b.IsGBCCart() || b.IsBooting() { // CGB boot ROM makes use of both banks
 				copy(b.vRAM[b.data[types.VBK]&0x1][:], b.data[0x8000:0xA000])
@@ -289,6 +289,10 @@ func (b *Bus) Boot() {
 
 	if b.model == types.CGBABC || b.model == types.CGB0 {
 		b.Set(types.VBK, 0xFE)
+
+		if !b.IsGBCCart() {
+			b.vRAMBankMask = 0
+		}
 	}
 
 	b.bootROMDone = true
@@ -327,6 +331,9 @@ func (b *Bus) Write(addr uint16, value byte) {
 			}
 			b.bootROMDone = true
 			value = 0xff
+			if b.isGBC && !b.IsGBCCart() {
+				b.vRAMBankMask = 0
+			}
 
 			for _, f := range b.bootHandlers {
 				f()
@@ -374,9 +381,6 @@ func (b *Bus) Write(addr uint16, value byte) {
 		default:
 			if handler := b.writeHandlers[addr&0xFF]; handler != nil {
 				// check to see if a component has reserved this address
-				if addr == 0xff15 {
-					panic("how")
-				}
 				value = handler(value)
 			} else if addr <= 0xff7f {
 				return

internal/ppu/ppu.go

@@ -306,9 +306,11 @@ func New(b *io.Bus, s *scheduler.Scheduler) *PPU {
 	})
 
 	b.RegisterBootHandler(func() {
-		p.BGColourisationPalette = p.ColourPalette[0]
-		p.OBJ0ColourisationPalette = p.ColourSpritePalette[0]
-		p.OBJ1ColourisationPalette = p.ColourSpritePalette[1]
+		if b.IsGBC() && !b.IsGBCCart() {
+			p.BGColourisationPalette = p.ColourPalette[0]
+			p.OBJ0ColourisationPalette = p.ColourSpritePalette[0]
+			p.OBJ1ColourisationPalette = p.ColourSpritePalette[1]
+		}
 		p.TileMaps = [2][32][32]TileEntry{}
 	})