CPU testing

lib/io.c

@@ -0,0 +1,32 @@
+#include <io.h>
+
+static char serial_data[2];
+
+u8 io_read(u16 address){
+    if(address == 0xFF01) {
+        return serial_data[0];
+    }
+
+    if(address == 0xFF02) {
+        return serial_data[1];
+    }
+
+    printf("UNSUPPORTED io_read(%04X)\n", address);
+    return 0;
+}
+
+
+void io_write(u16 address, u8 value){
+    if(address == 0xFF01) {
+        serial_data[0] = value;
+        return;
+    }
+
+    if(address == 0xFF02) {
+        serial_data[1] = value;
+        return;
+    }
+
+    printf("UNSUPPORTED io_write(%04X)\n", address);
+}
+