diff --git a/desmume/src/FIFO.c b/desmume/src/FIFO.c
index ef299ad99..bcd453cff 100644
--- a/desmume/src/FIFO.c
+++ b/desmume/src/FIFO.c
@@ -23,7 +23,7 @@
 
 void FIFOInit(FIFO * fifo)
 {
-	unsigned long i;
+        u32 i;
 
 	fifo->begin = 0;
         fifo->end = 0;
@@ -34,7 +34,7 @@ void FIFOInit(FIFO * fifo)
         fifo->error = FALSE;
 }
 
-void FIFOAdd(FIFO * fifo, unsigned long v)
+void FIFOAdd(FIFO * fifo, u32 v)
 {
 	if(fifo->full) 
         {
@@ -47,14 +47,14 @@ void FIFOAdd(FIFO * fifo, unsigned long v)
         fifo->empty = FALSE;
 }
        
-unsigned long FIFOValue(FIFO * fifo)
+u32 FIFOValue(FIFO * fifo)
 {
 	if(fifo->empty)
         {
         	fifo->error = TRUE;
                 return 0;
         }
-        unsigned long v = fifo->data[fifo->begin];
+        u32 v = fifo->data[fifo->begin];
         fifo->begin = (fifo->begin + 1)& 0x1FFF;
         fifo->empty = (fifo->begin == fifo->end);
         return v;
diff --git a/desmume/src/FIFO.h b/desmume/src/FIFO.h
index 2fa05277e..0bc6eb095 100644
--- a/desmume/src/FIFO.h
+++ b/desmume/src/FIFO.h
@@ -30,17 +30,17 @@ extern "C" {
 
 typedef struct
 {
-       unsigned long data[0x2000];
-       unsigned long begin;
-       unsigned long end;
+       u32 data[0x2000];
+       u32 begin;
+       u32 end;
        BOOL full;
        BOOL empty;
        BOOL error;
 } FIFO;
 
 void FIFOInit(FIFO * fifo);
-void FIFOAdd(FIFO * fifo, unsigned long v);
-unsigned long FIFOValue(FIFO * fifo);
+void FIFOAdd(FIFO * fifo, u32 v);
+u32 FIFOValue(FIFO * fifo);
 
 #ifdef __cplusplus
 }