Dear Sir, My program codes are as follows, show.asm ;Main====================================== ORG 0000H ACALL INIT ;------------------------------------ MOV DPTR,#W0 ACALL SHOW MOV DPTR,#W1 ACALL SHOW ;-------------------------------- SHOW: MOV R2,#64 LOOP1: MOV R5,#192 LOOP0: MOV A,#0 MOVC A,@A+DPTR ACALL WRDATA INC DPTR DJNZ R5,LOOP0 DJNZ R2,LOOP1 RET ;table0 ;--------------------------------- W0: DB 08H,0A0H, 08H,0A0H, 08H,0A0H ;table1 ;--------------------------------- W1: DB 08H,0A0H, 08H,0A0H, 08H,0A0H END If I want to put table0 into bank0 and table1 into bank1, how do I organize it? for example, common.asm ;Main====================================== ORG 0000H ACALL INIT ;------------------------------------ MOV DPTR,#W0 ACALL SHOW MOV DPTR,#W1 ACALL SHOW ;-------------------------------- SHOW: MOV R2,#64 LOOP1: MOV R5,#192 LOOP0: MOV A,#0 MOVC A,@A+DPTR ACALL WRDATA INC DPTR DJNZ R5,LOOP0 DJNZ R2,LOOP1 RET bank0.asm ;table0-------------------------- W0: DB 08H,0A0H, 08H,0A0H, 08H,0A0H END bank1.asm ;table1------------------------------- W1: DB 08H,0A0H, 08H,0A0H, 08H,0A0H END ;========================================= After running A51 & LX51, the errors are as follows, .\common.asm : Error A45: undefined symbol ;======================================= W0 and W1 are undefined symbols Could you tell me how to solve it? Thanks a lot! James