奇怪，这个程序无法通过编译。
大家看看：
org 0000h
ajmp keyscan
;org 0003h
;reti
;org 000bh
;reti
;org 0013h
;reti
;org 001bh
;reti
;org 0023h
;reti
;org 002bh
;reti
org 0100h
keyscan: mov p1,#0f0h
clr p1.0
mov a,p1
anl a,#0f0h
cjne a,#0f0h,keyc0n
setb p1.0
clr p1.1
mov a,p1
anl a, #0f0h
cjne a,#0f0h,keyc0n
setb p1.1
clr p1.1
mov a,p1
anl a, #0f0h
cjne a,#0f0h,keyc0n
setb p1.2
clr p1.2
mov a,p1
anl a, #0f0h
cjne a,#0f0h,keyc0n
setb p1.3
clr p1.1
mov a,p1
anl a, #0f0h
cjne a,#0f0h,keyc0n
ret
keycon: acall dl10ms
mov a,p1
anl a,#0f0h
cjne a,#0f0h,keyche
ret
keyche: mov a,p1
cjne a,#0eeh,key0
cjne a,#odeh,key1
cjne a,#obeh,key2
cjne a,#7eh,key3 ;3
cjne a,#0edh,key4 ;4
cjne a,#oddh,key5
cjne a,#obdh,key6
cjne a,#7dh,key7
cjne a,#oebh,key8 ;8
cjne a,#odbh,key9
cjne a,#obbh,keya
cjne a,#7bh,keyb ;11
cjne a,#oe7h,keyc ;12
cjne a,#od7h,keyd
cjne a,#ob7h,keye
cjne a,#77h,keyf
key0: mov a,0c0h
mov p0,a
ljmp keyscan
key1: mov a,0f9h
mov p0,a
ljmp keyscan
key2: mov a,0a4h
mov p0,a
ljmp keyscan
key3: mov a,0b0h
mov p0,a
ljmp keyscan
key4: mov a,99h
mov p0,a
ljmp keyscan
key5: mov a,92h
mov p0,a
ljmp keyscan
key6: mov a,82h
mov p0,a
ljmp keyscan
key7: mov a,0f8h
mov p0,a
ljmp keyscan
key8: mov a,80h
mov p0,a
ljmp keyscan
key9: mov a,90h
mov p0,a
ljmp keyscan
keya: mov a,88h
mov p0,a
ljmp keyscan
keyb: mov a,83h
mov p0,a
ljmp keyscan
keyc: mov a,0a7h
mov p0,a
ljmp keyscan
keyd: mov a,0a1h
mov p0,a
ljmp keyscan
keye: mov a,83h
mov p0,a
ljmp keyscan
keyf: mov a,8eh
mov p0,a
ljmp keyscan
dl512: mov r1,#0ffh
loop: djnz r1,loop
ret
dl10ms: mov r0,#10
loop2: lcall dl512
djnz r0,loop2
ret
end
是个键扫描，然后led显示程序。
错误：
c:\windows\desktop\qw.a51(21): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(26): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(31): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(36): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(41): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(50): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(51): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(54): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(55): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(57): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(58): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(59): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(61): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(62): error a45: undefined symbol (pass-2)
c:\windows\desktop\qw.a51(63): error a45: undefined symbol (pass-2)
