+/* ao_button.c */
+#ifdef HAS_BUTTON
+void
+ao_p0_isr(void) ao_arch_interrupt(13);
+
+void
+ao_p1_isr(void) ao_arch_interrupt(15);
+
+void
+ao_p2_isr(void);
+
+#define HAS_P2_ISR 1
+
+#endif
+
+void
+ao_button_init(void);
+
+char
+ao_button_get(void) __critical;
+
+void
+ao_button_clear(void) __critical;
+
+/* ao_string.c */
+
+void
+_ao_xmemcpy(__xdata void *dst, __xdata void *src, uint8_t count);
+
+#define ao_xmemcpy(d,s,c) _ao_xmemcpy(d,s,c)
+
+void
+_ao_xmemset(__xdata void *dst, uint8_t value, uint8_t count);
+
+#define ao_xmemset(d,v,c) _ao_xmemset(d,v,c)
+
+int8_t
+_ao_xmemcmp(__xdata void *a, __xdata void *b, uint8_t count);
+
+#define ao_xmemcmp(d,s,c) _ao_xmemcmp((d), (s), (c))
+