asample3.a51

c51学习的好书！

NAME    CHAR_IO
PUBLIC  PUTCHAR
CHAR_ROUTINES  SEGMENT  CODE
VAR2           SEGMENT  DATA
        RSEG  CHAR_ROUTINES
PUTCHAR:                          ; 子程序PUTCHAR从串行口输出单个字符
        JNB  TI,$
        CLR  TI
        MOV  SBUF,A
        RET
        RSEG  VAR2
DUMMY:  DS    40H
        END