#define AO_NUM_STDIOS (HAS_USB + PACKET_HAS_SLAVE + USE_SERIAL_STDIN)
__xdata struct ao_stdio ao_stdios[AO_NUM_STDIOS];
-__data int8_t ao_cur_stdio;
-__data int8_t ao_num_stdios;
+__pdata int8_t ao_cur_stdio;
+__pdata int8_t ao_num_stdios;
void
putchar(char c)