Finish ppu, and mbc1 mapping

lib/io.c

@@ -3,10 +3,14 @@
 #include <cpu.h>
 #include <dma.h>
 #include <lcd.h>
+#include <gamepad.h>
 
 static char serial_data[2];
 
 u8 io_read(u16 address){
+    if(address == 0xFF00) {
+        return gamepad_get_output();
+    }
     if(address == 0xFF01) {
         return serial_data[0];
     }
@@ -27,14 +31,24 @@ u8 io_read(u16 address){
         return cpu_get_int_flags();
     }
 
+    if(BETWEEN(address, 0xFF10, 0xFF3F)) {
+        //ignore sound
+        return 0;
+    }
+
     printf("UNSUPPORTED io_read(%04X)\n", address);
     return 0;
 }
 
 
 void io_write(u16 address, u8 value){
+    if(address == 0xFF00) {
+        gamepad_set_sel(value);
+        return;
+    }
     if(address == 0xFF01) {
         serial_data[0] = value;
+        printf("%c", value);
         return;
     }
 
@@ -58,6 +72,11 @@ void io_write(u16 address, u8 value){
         return;
     }
 
+    if(BETWEEN(address, 0xFF10, 0xFF3F)) {
+        //ignore sound
+        return;
+    }
+
     printf("UNSUPPORTED io_write(%04X)\n", address);
 }