o add custom chip for mmio

tools/bsnes/chip/cmmio/cmmio.cpp

@@ -0,0 +1,35 @@
+#include <../base.hpp>
+#include <../cart/cart.hpp>
+#include "cmmio.hpp"
+
+
+void CMMIO::init() {
+}
+
+void CMMIO::enable() {
+  memory::mmio.map(0x3000, *this);
+  memory::mmio.map(0x3001, *this);
+  memory::mmio.map(0x3002, *this);
+  memory::mmio.map(0x3004, *this);
+}
+
+void CMMIO::power() {
+  reset();
+}
+
+void CMMIO::reset() {
+}
+
+uint8 CMMIO::mmio_read(unsigned addr) {
+  addr &= 0xffff;
+  printf("CMMIO::mmio_read 0x%x",addr);
+  return cpu.regs.mdr;
+}
+
+void CMMIO::mmio_write(unsigned addr, uint8 data) {
+  addr &= 0xffff;
+  printf("CMMIO::mmio_write 0x%x 0x%x",addr,data);
+}
+
+CMMIO::CMMIO() {
+}