51单片机连接机智云小案例：stc89c52+esp8266-01

楠楠

楼主用keil编译出了好多错
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  NUM_USART
    MODULE:  Smart_Usart.obj (SMART_USART)
    ADDRESS: 0BB4H
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  USRTLEN
    MODULE:  Smart_Usart.obj (SMART_USART)
    ADDRESS: 0BBBH
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  USARTBUF
    MODULE:  Smart_Usart.obj (SMART_USART)
    ADDRESS: 0BC2H
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  USARTBUF
    MODULE:  Smart_Usart.obj (SMART_USART)
    ADDRESS: 0BC8H
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  USRTLEN
    MODULE:  Smart_Usart.obj (SMART_USART)
    ADDRESS: 0BCFH
** ERROR L118: REFERENCE MADE TO ERRONEOUS EXTERNAL
    SYMBOL:  USARTBUF
好多这个错，是怎么回事

楠楠

想问下APP开发教程在哪