keil4单片机编程遇到的问题，搞不懂那错了

*** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS
    SEGMENT: ?PR?_LCDWRITECOM?LCD1602
*** WARNING L16: UNCALLED SEGMENT, IGNORED FOR OVERLAY PROCESS
    SEGMENT: ?PR?_SHUMAGUAN?SHUMAGUAN
*** WARNING L1: UNRESOLVED EXTERNAL SYMBOL
    SYMBOL:  _DISP0
    MODULE:  main.obj (MAIN)
*** WARNING L1: UNRESOLVED EXTERNAL SYMBOL
    SYMBOL:  LCDINIT
    MODULE:  main.obj (MAIN)
*** WARNING L2: REFERENCE MADE TO UNRESOLVED EXTERNAL
    SYMBOL:  LCDINIT
    MODULE:  main.obj (MAIN)
    ADDRESS: 090FH
*** WARNING L2: REFERENCE MADE TO UNRESOLVED EXTERNAL
    SYMBOL:  _DISP0
    MODULE:  main.obj (MAIN)
    ADDRESS: 091EH

都是警告，不用理的