Add mapper 468

src/boards/468_lf36.h

@@ -0,0 +1,46 @@
+#define LF36_prg regByte[0]
+#define LF36_irq regByte[1]
+#define LF36_counter regWord[0]
+
+static void LF36_sync () {
+	int OR  =prgOR | mapperFlags &0x08;
+	setprg8(0x8000,           0x04 | OR);
+	setprg8(0xA000,           0x05 | OR);
+	setprg8(0xC000, LF36_prg &0x07 | OR);
+	setprg8(0xE000,           0x07 | OR);
+	setchr8(0);
+	setmirror(mapperFlags &4? MI_H: MI_V);
+}
+
+static DECLFW(LF36_writeReg) {
+	switch (A &0xE000) {
+	case 0x8000: LF36_irq =0; break;
+	case 0xA000: LF36_irq =1; break;
+	case 0XE000: LF36_prg =V; sync(); break;
+	}
+}
+
+static void FP_FASTAPASS(1) LF36_cpuCycle(int a) {
+	while (a--) {
+		if (LF36_irq) {
+			if (++LF36_counter &0x1000)
+				X6502_IRQBegin(FCEU_IQEXT);
+			else
+				X6502_IRQEnd(FCEU_IQEXT);
+		} else {
+			X6502_IRQEnd(FCEU_IQEXT);
+			LF36_counter =0;
+		}
+	}
+}
+
+void LF36_reset(uint8 clearRegs) {
+	sync =LF36_sync;
+	MapIRQHook =LF36_cpuCycle;
+	SetWriteHandler(0x8000, 0xFFFF, LF36_writeReg);
+	sync();
+}
+
+#undef LF36_prg
+#undef LF36_irq
+#undef LF36_counter