串口通信的中断处理程序不执行怎么办
我想利用串口扩展芯片74HC164做一个流水灯。没成功。用keil单步运行时发现中断处理程序没有执行，请高人指点

Assembly code

ORG 0000HLJMP MAINORG 0023HLCALL DELAY    INC R2RETIORG 0050HMAIN:SETB P1.0MOV SCON,#0MOV R2,#0MOV R3,#4MOV A,#0MOV DPTR,#TABSETB EASETB ESBB:DJNZ R3,EEMOV R2,#0EE:MOV A,R2MOVC A,@A+DPTRMOV SBUF,AAA:JNB TI,AACLR TILJMP BBDELAY:MOV R4,#2L3: MOV R2 ,#250L1: MOV R3 ,#250L2: DJNZ R3 ,L2 DJNZ R2 ,L1DJNZ R4 ,L3 RETTAB:DB 00111111B,11001111B,11110011B,11111100BEND

http://hi.csdn.net/attachment/201112/23/9913057_1324627488BNwl.jpg

[解决办法]
将延时子程序中R2R3R4换成R5R6R7