diff --git a/pico/pico_int.h b/pico/pico_int.h
index 088c7aa5..09cefdfd 100644
--- a/pico/pico_int.h
+++ b/pico/pico_int.h
@@ -33,12 +33,12 @@ extern "C" {
 #endif
 
 
-typedef unsigned char  u8;
-typedef signed char    s8;
-typedef unsigned short u16;
-typedef signed short   s16;
-typedef unsigned int   u32;
-typedef signed int     s32;
+typedef uint8_t        u8;
+typedef int8_t         s8;
+typedef uint16_t       u16;
+typedef int16_t        s16;
+typedef uint32_t       u32;
+typedef int32_t        s32;
 typedef uintptr_t      uptr; // unsigned pointer-sized int
 
 // ----------------------- 68000 CPU -----------------------