; ASxxxx/sdas8051 syntax. LED anodes via 1k to +5V,
; cathodes at P1.0 (pass) and P1.1 (fail).
.module test
.area CODE (ABS)
.org 0x0000
    ljmp start
.org 0x0030
start:
    mov 0x90,#0xff
    mov dptr,#0x0000
    mov a,#0x5a
    movx @dptr,a
    clr a
    movx a,@dptr
    cjne a,#0x5a,fail

good:
    cpl 0x90
    mov r7,#0xff
delay1:
    mov r6,#0xff
delay2:
    djnz r6,delay2
    djnz r7,delay1
    sjmp good
fail:
    clr 0x91
    sjmp fail